Climate Change Vulnerability Assessment. for Selected Stormwater Infrastructure FINAL. August 2014

Transcription

1 Climate Change Vulnerability Assessment for Selected Stormwater Infrastructure August 2014 FINAL

2 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 1 Executive Summary Introduction The Greater Toronto Airports Authority s (GTAA s) mandate is to ensure that the Airport s facilities and air services match the needs of the growing population of the GTA and south-central Ontario. The Greater Toronto Area (GTA) is a 7,125 km 2 area consisting of the City of Toronto plus the neighbouring regional municipalities of Halton, Peel, York, Durham, and their 24 constituent municipalities. Toronto Pearson is the principal airport for southern Ontario. To address this significant responsibility, the GTAA embarked on a 30-year vision for the development of Toronto Pearson in Since that time, the GTAA s primary focus has been to replace obsolete airport infrastructure in order to improve the facilities and services that Toronto Pearson has to offer the region it serves. Toronto Pearson is located 25 km northwest of Toronto s central business district in the heart of the southern Ontario region. The Airport is surrounded by a variety of industrial, commercial and residential land uses and is bound by a series of major highways and regional arterial roads. The area of land within the current operational boundary of Toronto Pearson covers 1,867 ha (4,613 acres) and encompasses airside facilities, passenger and cargo terminals, parking, access roads, business aviation, and aviation support facilities. Due to its favourable location within Canada and North America, Toronto Pearson not only serves those visiting or living within south-central Ontario, but also the growing number of passengers using the Airport as a connecting point for onward journeys. Toronto s central gateway location means that an estimated 60 per cent of North America s population is within a 90-minute flight from Toronto Pearson. PIEVC Engineering Protocol To assess the potential impacts of climate change on public infrastructure and to advance planning and prioritization of adaptation strategies, Engineers Canada and its partners have established the Public Infrastructure Engineering Vulnerability Committee (PIEVC). Co-funded by Engineers Canada and Natural Resources Canada, the PIEVC is comprised of representatives from all three levels of government as well as non-governmental organizations. The Committee oversees the planning and execution of a national engineering assessment of the vulnerability of Canadian public infrastructure to climate change. The work of the PIEVC commenced in 2007 with a scoping study to examine the current state of infrastructure, the availability of climate data, and indicators of adaptive capacity during the development of the PIEVC Protocol for infrastructure vulnerability assessment. The Protocol was subsequently evaluated through seven pilot studies, which were included in the first national assessment report completed by the PIEVC in April Based on the success of these early studies and the interest among public infrastructure stakeholders in the results, Engineers Canada is continuing to promote the application of the PIEVC protocol in additional case studies in four priority infrastructure categories: buildings, roads and associated structures, stormwater and wastewater systems and water resources infrastructure. The results of these studies will be used to continue to refine and improve the protocol and further the program goals of supporting vulnerability assessment and adoption of best practices at the national scale. The GTAA decided to undertake an engineering vulnerability assessment of infrastructure in the context of both the existing climate and future climate change, using the PIEVC Protocol. The PIEVC Engineering Protocol for Climate Change Infrastructure Vulnerability Assessment (Version 10, October, 2011),

3 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 2 hereafter referred to as the Protocol, is a step-by-step process to conduct an engineering vulnerability assessment on infrastructure due to climate change. Potential issues and concerns arising from changing climate: Airport infrastructure is considered vulnerable to the types of weather related stresses that will be exacerbated by climate change; Climate change could threaten airport infrastructure; Potential flooding of runways, taxiways, aircraft manoeuvring areas, access roads could cause operational delays and physical damage to airport property; Stormwater runoff may exceed capacity of drainage and drainage systems; Potential wind damage to terminals, navigation equipment and signage; Disruption of airport operations, ground access, services supplied to the airport; Change in de-icing operations (increase, decrease of de-icing fluid quantities); and, Different needs for snow clearance and de-icing include combination of less snow but more ice. The five steps within the Protocol carried out to complete the vulnerability assessment were as follows: Step 1 Project Definition The boundary conditions for the vulnerability assessment were determined in Step 1. A description of the infrastructure including its location, age, loads, historical climate, and other relevant factors were developed. Initially, only certain components of the drainage and stormwater management system and the Spring Creek triple cell box culvert at Toronto Pearson will be assessed in detail. Ultimately, other infrastructure at Toronto Pearson will be assessed. Step 2 Data Gathering and Sufficiency The specific features of the infrastructure to be considered in the assessment as well as the applicable climate information were identified and evaluated for sufficiency in Step 2. Step 3 Risk Assessment The interactions between the infrastructure, the climate, and any other factors that could lead to vulnerability were identified in Step 3. This included identifying specific infrastructure components, specific climate change parameter values, and specific performance goals. In this step, the infrastructure s response to the climate parameters was identified. Based on the Protocol, the overall risk value associated with an interaction between an infrastructure component and a climate related event was determined by multiplying the probability of the event occurring by the severity of the impact. Scales of 0 7 were established for the probability of the interactions occurring and the severity resulting from the interaction. The Protocol provides three alternate methods each for the probability and severity scales from which the most appropriate method for this assessment was selected.

4 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 3 Performance response categories were established based on the most likely response of an infrastructure component to contemplated climate events. The performance response categories were based on professional judgment and experience. Instead of assessing the severity scale factor of each performance response for individual infrastructure components, all the performance responses that were relevant were check marked, and only one severity scale factor was applied. The severity scale factor that was applied was based on judgment of the performance response that was most critical to the individual infrastructure-climate interaction. The following points summarize the risk assessment findings for Toronto Pearson: Out of the 11,640 interactions identified for the risk assessment, about 27% had a risk score of above 12 and were therefore considered to be relevant for further consideration during engineering analysis. No interactions had a risk score of above 36, therefore none were considered to be high risk as defined by the Protocol; About 10% of low risk interactions increased to a medium risk score as a result of climate change. The highest increases were associated with extreme heavy rainfalls, heavy rainfalls, freezing rain, ice storms, and hurricanes/tropical storms. About 10% of medium risk interactions decreased to a low risk score as a result of climate change. The highest decrease was by a score of 6. This was associated with potential future decreases in cold waves and freeze-thaw cycles. Approximately 90% of interactions maintained their risk classification. Step 4 Engineering Analysis The impact on the infrastructure and its capacity resulting from the projected climate change loads was assessed in Step 4. This included a focused engineering analysis on the relationships determined to have vulnerability in Step 3. The infrastructure-climate interactions that scored a medium risk value (between 12 and 36) in Step 3 were analyzed further under this step. The analysis included a determination of the relationship between the loads placed under both existing and future conditions and the infrastructure components and their capacity. Vulnerability exists when the infrastructure has insufficient capacity to withstand the loads placed upon it. Therefore, there is a capacity deficit when vulnerability exists. There is adaptive capacity when the infrastructure is resilient i.e. it has sufficient capacity to withstand the climate change effects without compromising the ability of the infrastructure to perform as required. The Protocol dictates that the total loading and total capacity be used to calculate the Vulnerability Ratio. In general, data was insufficient to complete the engineering analysis in the specific quantitative method prescribed by the Protocol. In determining the climate load from the results of the Climate Analysis and Projections, the units were generally represented by number of occurrences per year, or a probability of the event occurring in a given year. This definition allowed the assignment of an existing and future climate load, however made the determination of the capacity of a component impossible in any meaningful, scientific way. For example, it is impossible to determine how many ice storms the bridge deck could withstand in a given year, or to put any number to the capacity of the operation buildings and tornadoes.

5 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 4 In light of the above, experience and professional engineering judgment were utilized to estimate whether or not the component was vulnerable or not, to a singular, or multiple, occurrences of the climate parameter. Therefore, the vulnerability ratio was qualitatively assessed to being either greater or less than one. If the total capacity was estimated to be greater than the total load, then the vulnerability ratio was listed as less than one. A vulnerability ratio of less than one means that the infrastructure component was resilient and not vulnerable to the climate parameter. If the total capacity was estimated to be less than the total load, then the vulnerability ratio would be greater than one, indicating that vulnerability exists. The Engineering Analysis generally resulted in a determination of the vulnerability of the infrastructure components to a single occurrence of the climate event, rather than the probability or frequency of the event. For example, personnel could be identified as being vulnerable to a freezing rain event for both existing and future conditions, with no distinction made regarding whether personnel are more or less vulnerable in the future with an increased probability of freezing rain events, as there is no information available with which to determine whether a change in frequency would increase the vulnerability of the components. The above notwithstanding, it was possible to make a determination of the difference between existing and future risk for the components and interactions identified as vulnerable by revisiting the results of the Risk Assessment completed in Step 3. In that assessment, the probability scores did change for some climate events, from the existing to future conditions, and the associated risk scores changed as well. Based on a comparison of those existing and future risk scores for vulnerable components and interactions, the potential effect of climate change in modifying risk to those components could be determined. The following sections provide a summary of the results for Toronto Pearson. The following points summarize the vulnerabilities identified in the engineering analysis step: A total of 3199 interactions were considered in the engineering analysis step; There were 7 interactions assessed to be vulnerable; and, Generally, the vulnerabilities exist to the following climate events: Extreme Heavy Rainfall, Heavy Rainfall and 5-Day Heavy Rainfall. Step 5 Recommendations The limitations and recommendations on the observations and findings of the infrastructure vulnerability assessment in Steps 1 to 4 were determined in Step 5. The main objective of this assessment is to identify components of the infrastructure which are at increased risk of failure, damage, deterioration, reduced operational effectiveness, and/or reduced life cycle from potential future changes in climate. Additionally, the study contains recommendations for remedial action to minimize the vulnerability and/or complete further study to further quantify the risks. During the completion of Step 5, recommendations were provided for actions to be taken to address the potential vulnerabilities, or for further investigations for GTAA to determine the extent of the vulnerability. These recommendations were provided for each of the components which were determined to be vulnerable.

6 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 5 Climate Analysis and Projections The study involved an assessment of the vulnerabilities of the facilities to current climate (existing and/or historical conditions), as well as future climate change at the 2050 time horizon. This study included assessment of the existing risks and vulnerabilities associated with the current climate, assessment of future risks and vulnerabilities, and an analysis of the change between the two. The climate analysis and projections portion of this study included the establishment of a set of climate parameters describing climatic and meteorological phenomena relevant to the geographic areas of the Toronto Pearson. The following climate parameters were selected for analysis in this study: High Temperature, Low Temperature, Heat Wave, Cold Wave, Extreme Diurnal Temperature Variability, Freeze Thaw, Extreme Heavy Rain, Heavy Rain, Heavy 5-Day Total Rainfall, Rain Frequency, Wet Days, Winter Rain, Freezing Rain, Ice Storm, Heavy Snow, Snow Accumulation, Blowing Snow/Blizzard, Lightning, Hailstorm, Hurricane/Tropical Storm, High Wind, Tornado, Drought/Dry Period, Heavy Fog, Dust Storm, Frost and Acid Rain. Specific definitions for the climate parameters analyzed were established and were based on three factors: a) the usefulness of the climate parameter in determining vulnerability, b) the availability of information, and c) the ability to relate this information to a probability. In addition, two tiers of parameter definitions were established based on the nature of each specific climate phenomenon. Tier one definitions refer to commonly occurring climate phenomena and were defined as the probability of exceeding the historical average occurrence, whereas Tier Two definitions refer to extreme events and were defined as the frequency of occurrence in a given year. The most common time frame used for analysis of historical climate data was 1971 to 2000, as this is the most recent 30-year climate normal period. Wherever possible, the time frame used for future projections was the 30-year period of 2041 to 2070, or more commonly expressed as the 2050s. Assessment of vulnerability beyond this horizon was not conducted as it was agreed among the study team members that this would likely surpass the design life of the infrastructure without the undertaking of significant reconstruction or rehabilitation efforts. The level of uncertainty associated with future climate projections also increases significantly beyond the middle of this century, which would potentially call into question the usefulness of the results. The following Climate Parameters experienced no change in Probability Score from historical to future: Winter Rain, Heavy Snow, Blowing Snow/Blizzard, Lightning, Hailstorm, High Wind, Tornado, Dust Storm, Acid Rain and Heavy Fog. In addition to determining Probability Scores, known or calculated climate parameter frequencies were used as climate loads in the Engineering Analysis phase of the project. The study did not include a detailed hydrologic or hydraulic assessment of the stormwater facilities. A separate study by Cole Engineering Group Ltd is being undertaken to update the Master Stormwater Implementation Plan and Flood Risk Analysis. Through previous studies, the stormwater infrastructure have generally been found to be resilient to a variety of high inflow conditions below design magnitudes. For the purposes of this study, changes to high inflow regimes were examined only from a general, qualitative basis in the assessment in consideration of indirect or secondary effects.

7 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 6 Recommendations Some specific key recommendations from the study are as follows: GTAA should review the emergency operational plans currently in place to ensure they are adequate for all types of climate events rain, snow, ice, high winds. From this review, it would be prudent to extrapolate for the extreme events considered in this assessment to ensure operations personnel are comfortable with the safeguards in place. There were a number of climate-component interactions that had an overall low risk score under both existing and future conditions due to a low probability of occurrence, but for which impacts would be extremely severe. These risk interactions were considered to be important, since the high severities indicated the potential for a critical loss of function; it is therefore advisable to consider the potential impacts and consequences of these high-impact events, and potentially to also develop mitigation or response plans to address them. The main climate conditions involved in these interactions with low risk scores and high severities are extreme heavy rainfalls, tornados, and hurricane/tropical storms. Many of the recommendations of the study are based on assessed risk and vulnerability that are considered to remain the same or become greater as a result of the potential outcomes of climate change. However, assumptions regarding climate change outcomes were based on analysis of current climate understanding and predictive science, which in itself involves a great deal of uncertainty. It is therefore suggested that the recommendations of this study be revisited with updated climate analysis and projections if climate science is able to provide more precision or certainty in the future. Generally, the results of the engineering analysis demonstrate that the stormwater facilities have relatively low vulnerability to potential future climate change. Part of the reason for the relatively low vulnerability is the excellent condition that the stormwater facilities are in; this is due to combination of resilient design, a high quality of construction, consistent inspections and maintenance on the part of GTAA staff. The PIEVC protocol recommends that an adaptive management process be utilized to revisit the vulnerability assessment at defined intervals to incorporate new information including improved climate science and future climate projections. Considering the manner in which the climate analysis and projections portion of this study is organized, and the thorough documentation of the assumptions regarding the use of the information in the risk and vulnerability assessment, incorporating new climate-related information should be a relatively straightforward process. Additional climate parameters may also be incorporated by following the format in which the existing climate parameters are provided. The remaining portions of the study (Risk Assessment and Vulnerability Analysis) have been presented in this document according to the procedures prescribed by the PIEVC Protocol.

8 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 7 Conclusions Having utilized the protocol to assess the stormwater facilities and Spring Creek triple cell box culvert, the project team determined that, in general, the facilities have the capacity to withstand the existing and projected future climate (i.e. to the 2050s). The climate analysis revealed some changes in frequency of climate events that will result in a decrease in vulnerability for the infrastructure. With the generally higher temperatures projected for the study area, there will be less probability, or less frequency of the low temperature dependant events such as freeze/thaw, snow accumulation and cold wave. This reduced frequency of occurrence will result in a decreased potential vulnerability from the events. This can be viewed as a potential positive impact of future climate change. The climate events posing the highest vulnerability to the stormwater facilities, particularly in terms of number of components potentially vulnerable, are generally extreme events such as extreme heavy rainfalls. While this was an expected outcome, it should be highlighted that the current climate science indicates that the possibility of these events occurring is going to increase in the future. Many of the vulnerabilities exist to extreme weather events such as tornados or hurricanes, and while it is difficult to completely protect the infrastructure from events such as these, there are actions which can be taken to minimize the operational risks and prepare for the events. These include: reviewing emergency response plans, and completing operational tests where power, communication and back-up systems are lost. While the overall conclusion of the report is that the stormwater facilities are generally able to withstand expected changes in climate in the future, it will continue to be important to monitor some of the risks and vulnerabilities identified through the assessment, particularly as components continue to age. It will be important to preserve the high standard of maintenance and management that GTAA has devoted to the stormwater facilities to this point. It will also be prudent to monitor the progress in climate science so that if future projections are updated or improved, the infrastructure assessment can be revisited.

9 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 1 Executive Summary Table of Contents Introduction... i PIEVC Engineering Protocol... i Climate Analysis and Projections... v Conclusions... vii 1.0 Introduction Overview Project Objectives Project Scope Project Team Report Layout Project Definition Overview Study Location and Area Geography Jurisdictional Considerations General Description of Infrastructure at Toronto Pearson Study Area Climate Time Frames Used for Analysis Historical Future Assess Data Sufficiency Infrastructure Data Climate Data Data Gathering and Sufficiency Overview Stormwater Facility Infrastructure General Infrastructure Components Infrastructure of Interest Spring Creek Triple Cell Box Culvert Infrastructure General Infrastructure Components Infrastructure of Interest Climate Analysis Objectives... 44

10 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Methodology TRCA Vulnerability Assessment to Climate Change for Flood Control Dams, Toronto s Future Weather & Climate Drivers Study, Toronto s Climate Change Vulnerability Assessment for Culverts, Toronto HydroElectric System Public Infrastructure Engineering Vulnerability Assessment Study, Discussion Regarding Available Climate Data & Projections Process of Probability Scoring Other Potential Changes that May Affect the Infrastructure Assessment of Data Sufficiency Risk Assessment Overview Risk Assessment Methodology Using a Spreadsheet to Document the Risk Assessment Populating Title Columns of the Spreadsheets Yes/No Analysis Populating Header Rows of the Spreadsheets Using Assessment Spreadsheet to Calculate the Risk for Each Relevant Interaction Evaluating Potential Cumulative Effects Risk Assessment Workshop Establish the GTAA s Risk Tolerance Thresholds Rank the Risks Assess Data Sufficiency Infrastructure Data Climate Data Summary of Findings Engineering Analysis Overview Step 4 Engineering Analysis Calculate the Existing Load (L E ) Calculate the Climate Change Load (L C ) Calculate Other Change Loads (L O ) Calculate the Total Load (T E ) Calculate the Existing Capacity (C E ) Calculate the Projected Change in Existing Capacity Arising from Aging/Use of the Infrastructure Calculate Additional Capacity Calculate the Projected Total Capacity (CT) Calculate Vulnerability Ratio... 79

11 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Calculate Capacity Deficit Spring Creek Culvert Assess Data Sufficiency Evaluate Need for Additional Risk Assessment Summary of Findings Complete Engineering Analysis Tables Recommendations Overview Limitations Major Assumptions Conclusions References Infrastructure Climate Data PIEVC Case Study

12 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 4 LIST OF FIGURES Figure 1.1 Climate Change Scenarios for Temperature... 1 Figure 1.2 PIEVC Process... 2 Figure 2.1 Project Definition Process Flowchart... 5 Figure 2.2 General Location of Toronto Pearson... 6 Figure 2.3 Aerial Photo of Toronto Pearson... 7 Figure 2.4 Toronto Pearson Jurisdictional Map... 8 Figure 2.5 Average Temperature at Pearson Airport ( ) Figure 2.6 Extreme Temperature Pearson Airport ( ) Figure 2.7 Precipitation at Pearson Airport ( ) Figure 2.8 Gust Winds at Pearson Airport ( ) Figure 3.1 Data Gathering and Sufficiency Process Flowchart Figure 3.2 Access to electrical system and detention tank for the Aeroquay Facility Figure 3.3 View of SWM6 stormwater detention pond (typical of dry detention ponds) Figure 3.4 View of Pond 2 stormwater detention pond (similar to Pond 4) Figure 3.5 View of Aeroquay Facility s underground storage tank Figure 3.6 Metal weir overflow plates in Cell 1 of the Moore Creek Facility Figure 3.7 Outlet from WM4A Figure 3.8 Cargo diversion chamber bypass in Moore Creek Facility Figure 3.9 Sluice gate for the SWM4 detention pond Figure 3.10 Exterior sluice gate control at Moore Creek Facility Figure 3.11 Oil/water skimmer in the Aeroquay Facility Figure 3.12 The north face of the electrical and instrumentation control building for Moore Creek Facility Figure 3.13 Electrical and instrumentation control panel in the Moore Creek Facility electrical building 27 Figure 3.14 Level indicator electronics in the Moore Creek Facility electrical and instrumental control building Figure 3.15 Gas detector electronics in Moore Creek Facility electrical building Figure 3.16 Gas detector inside Moore Creek Facility tank Figure 3.17 View of berm at Juliet Pond Figure 3.18 Locations of Toronto Pearson Stormwater Facilities Figure 3.19 Carlingview Stormwater Facility, Aeroquay Stormwater Facility and SWM Figure 3.20 Stormwater Pond 6B, Pond 2, and Pond Figure 3.21 Etobicoke Creek Facility and A Figure 3.22 Moore Creek Stormwater Facility and Spring Creek Storage Pond Figure 3.23 July 8, 2013 flooding in vicinity of SWM Figure 3.24 July 8, 2013 flooding in vicinity of SWM Figure 3.25 SWM4, SWM5, and SWM6 Facilities Figure 3.26 WM4A, FedEx Pond and Juliet Pond Figure 3.27 Inlet of Spring Creek Triple Cell Box Culvert Figure 3.28 Looking upstream inside westernmost cell of Spring Creek Triple Cell Box Culvert Figure 3.29 Channel downstream of Spring Creek Triple Cell Box Culvert Figure 3.30 Spring Creek Triple Cell Box Culvert overview Figure 3.31 Projected Change in Monthly Average Rainfall and Snowfall Figure 3.32 Projected Extreme Daily Rainfall Figure 3.33 Projected Change in Wind Figure 3.34 July 8, 2013 Rainfall Total Depth... 54

13 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 5 Figure 3.35 July 8, 2013 Maximum 60 Minute Intensity Figure 3.36 July 8, 2013 Maximum 120 Minute Intensity Figure 4.1 Risk Assessment Process Flowchart Figure 4.2 Summary of Findings Figure 5.1 Engineering Analysis Process Flowchart Figure 5.2 Projected future IDF curves compared to existing 100-year curve Figure 5.3 Model Water Surface Profile of Spring Creek Culvert for the Existing 100 and 350-year Design Storms and the Regional Storm Figure 6.1 Recommendations Process Flowchart LIST OF TABLES Table 2-1 Toronto Climate Normals ( ) Table 2-2 Design Life of Infrastructure Systems Table 3-1 Typical Stormwater Facility Infrastructure Inventory Table 3-2 Spring Creek Triple Cell Box Culvert Components Table 3-3 Summary of Extreme Weather Events for Table 3-4 Projected Future Weather Changes Compared to Recent Weather Table 3-5 Summary of Climate Parameters and Associated Probabilities Table 3-6 Prioritized Reference Documentation for Infrastructure Data Table 4-1 Probability Scale Factors Table 4-2 Severity Scale Factors Table 4-3 Sample Risk Assessment Matrix Table 4-4 Performance Response Considerations Table 4-5 Performance Response Considerations for Stormwater Facilities and Spring Creek Culvert Table 4-6 Workshop Attendees Table 4-7 Risk Tolerance Thresholds Table 4-8- Summary of Findings Table 5-1 Sample Layout of the Engineering Analysis Part Table 5-2 Sample Layout of the Engineering Analysis Part Table 5-3 Sample Layout of the Engineering Analysis Part Table 5-4 Vulnerable Components of the Stormwater Facilities (Vulnerability Ratio >1) Table 5-5 Vulnerable Components of Spring Creek Triple Cell Box Culvert (Vulnerability Ratio >1) Table 5-6 Engineering Analysis for Stormwater Facilities Table 5-7 Engineering Analysis for Spring Creek Culvert Table 6-1 Recommendations for the Vulnerable Components of the Stormwater Quality Control Facilities Table 6-2 Recommendations for the Vulnerable Components of the Stormwater Quantity Control Facilities APPENDICES Appendix A Climate Analysis & Projections Appendix B Risk Assessment Matrices Appendix C Ranked Risk Tables

14 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Introduction 1.1. Overview There is definitive evidence to suggest that the climate has changed, and is continuing to change. Climate change affects infrastructure, creating potential vulnerability in the operation and design of engineered systems. Vulnerability may exist because historic climate data is often used to form the basis of the design for public infrastructure. However, due to a changing climate, historic data used to design critical infrastructure may not reflect the climate of the future. As a result, infrastructure may be vulnerable since it may not have sufficient capacity or resiliency to accommodate the conditions created by the changing climate. Figure 1.1 Climate Change Scenarios for Temperature Source: International Panel on Climate Change (IPCC) Scenarios of Future Climate Driven by Population, Economics, and Technology Adoption The true extent of the effects of climate change may not be seen for several decades, however, given the long life of airport infrastructure, planning decisions must start now to consider these issues. The Greater Toronto Airports Authority (GTAA) decided to undertake a vulnerability assessment of infrastructure at Toronto Pearson International Airport (Toronto Pearson) with respect to the potential impacts from the existing climate and future climate change. GTAA representatives approached Mr. David Lapp of Engineers Canada. Engineers Canada established the Public Infrastructure Engineering Vulnerability Committee (PIEVC) to oversee a national engineering assessment of the vulnerability of Canadian public infrastructure to changing climate. PIEVC has developed a protocol to guide the vulnerability assessments. The PIEVC Protocol is a structured, formalized and documented process for engineers, planners and decision-makers to recommend measures to address the vulnerabilities and risks to changes in particular climate design parameters and other environmental factors from extreme climatic events. The

15 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 2 assessments help justify design, operations and maintenance recommendations and provide documented results that fulfill due diligence requirements for insurance and liability purposes. The Protocol systematically reviews historical climate information and projects the nature, severity and probability of future climate changes and events with the adaptive capacity of an individual infrastructure as determined by its design, operation and maintenance. It includes an estimate of the severity of climate impacts on the components of the infrastructure (i.e. deterioration, damage or destruction) to enable the identification of higher risk components and the nature of the threat from the climate change impact. This information can be used to make informed engineering judgments on what components require adaptation as well as how to adapt them e.g. design adjustments, changes to operational or maintenance procedures. Engineers Canada agreed to allow GTAA to use the PIEVC Protocol (Version 10 - October, 2011) for purposes of assessing its infrastructure. GTAA signed a licensing agreement with Engineers Canada Project Objectives The main objective of this study is to identify those components of infrastructure which are at increased risk of failure, damage, deterioration, reduced operational effectiveness, and/or reduced life cycle from climate changes. The nature and relative levels of risk are to be determined in order to make recommendations for remedial action and/or further study. The vulnerability assessment was based on Version 10, October 2011 of the PIEVC Protocol. There are five steps within the PIEVC Protocol, as shown in the process flowchart in Figure 1.2. Figure 1.2 PIEVC Process

16 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 3 The observations, conclusions, and recommendations derived from the vulnerability assessment can be used to effectively incorporate climate change adaptation in infrastructure design, development, and management. The Protocol provides a process to identify relevant interactions between climate and infrastructure. To assess infrastructure vulnerability to climate change, the following were evaluated: Selected Stormwater Infrastructure; Spring Creek Triple Cell Box Culvert; Historic, Recent, and Projected Climate; and, Historic and Forecasted Responses of the Infrastructure to the Climate. The following sections provide detailed descriptions and results from the completion of the five Protocol steps, as applied to the selected Stormwater Infrastructure and Spring Creek Triple Cell Box Culvert Project Scope There are considerably different types and extents of infrastructure at Toronto Pearson. A single vulnerability assessment study to address the impacts of climate change on all infrastructure at Toronto Pearson would be a massive and complex undertaking. Rather, the GTAA decided to initially undertake a pilot vulnerability assessment study, specifically addressing selected stormwater infrastructure and the Spring Creek Triple Cell Box Culvert. Completing a pilot vulnerability assessment for selected infrastructure allows GTAA to build internal capacity while undertaking the assessment; reviewing the results from the initial assessment; and then plan the next steps in adapting to climate change. The GTAA has made significant investments in its stormwater management infrastructure. The stormwater facilities were implemented coincident with re-development of Toronto Pearson and using up-to-date technologies and best management practices. A previous flood risk analysis study identified low potential for flooding that would cause either damage or delay to airport operations. However, the flood risk analysis studies relied on current stormwater management design criteria and did not account for climate change. The Flood Risk Analysis and Master Stormwater Implementation Plan are being updated separately. The updating of those studies was in part the catalyst to undertaking a vulnerability assessment to address climate change impacts. The Spring Creek Triple Cell Box Culvert is one component of infrastructure at Toronto Pearson that has previously been identified as posing a high flooding risk. It consists of a three cell concrete box culvert with each cell having dimensions 5 m x 3 m. It is located under Runway The culvert was designed to convey the 100-year design storm. The backwater effect caused by a more extreme storm event, such as a Regional Storm, would cause significant flooding risk, potentially overtopping the runway and impacting airport operations. It would also inundate the upstream Derry Road bridge under the jurisdiction of the Region of Peel. It is expected that the flooding risk and impact to operations would be heightened as a result of climate change. This vulnerability assessment study includes an assessment of the vulnerabilities of the facilities to current climate for existing conditions and to future climate change at the 2050 time horizon.

17 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 4 The study did not include a detailed hydrologic or hydraulic assessment of changed inflow regimes or the assessment of the risk of failure as a result of changes in the regime of extreme events Project Team Climate change engineering vulnerability assessment is a multidisciplinary process requiring a wide range of engineering, construction, operation, and maintenance skills and knowledge. Furthermore, the team must include deep knowledge of climatic and weather conditions relative to the project location. GTAA staff provided the primary technical and operations infrastructure knowledge. GTAA staff drove the project and were responsible for identifying and assessing the likely response of the infrastructure to projected climate change. This project was undertaken with internal resources from the GTAA, facilitated and guided by assistance from David Lapp of Engineers Canada and Alan Winter of Cole Engineering Group. Team members were as follows: Name Affiliation Job Title/Project Role Derek Gray GTAA Manager Environmental Services Chris Stewart GTAA Manager, Airside and Infrastructure Engineering Daphne De Souza GTAA Senior Environmental Officer Paul Wajda GTAA Senior Municipal Engineer Steve Thomas GTAA Senior Environmental Technician Alan Winter Cole Engineering Group Ltd. Facilitator John Chadwick Cole Engineering Group Ltd. Climate Specialist Cole Engineering was retained to facilitate the vulnerability assessment process and prepare this report Report Layout This report has been divided into the following main chapters: Section 2 Summarizes Step 1 of the PIEVC Engineering Protocol Project Definition. Section 3 Summarizes Step 2 of the PIEVC Engineering Protocol Data Gathering and Sufficiency. Section 4 This chapter describes Step 3 of the PIEVC Engineering Protocol Risk Assessment of the Stormwater Facilities and Spring Creek Triple Cell Box Culvert. Section 5 This chapter describes Step 4 of the PIEVC Engineering Protocol Engineering Analysis Section 6 This chapter presents the Main Conclusions and Recommendations of the overall study.

18 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Project Definition 2.1. Overview The objective of the first step of the Protocol is to determine the boundary conditions for the vulnerability assessment. This includes developing a description of the infrastructure including: Location of the vulnerability assessment; Infrastructure of concern; Historical climate; Time frames for analysis; Existing loads on the subject infrastructure; Age of the subject infrastructure; Jurisdictional considerations; Other relevant factors; and, Identification of major documents and information sources. Figure 2.1 provides a flowchart delineating the PIEVC process for Step 1 Project Definition. Figure 2.1 Project Definition Process Flowchart At the end of this step, data sufficiency was assessed by identifying proposed assumptions and their rationale Study Location and Area Geography Toronto Pearson is located 25 km northwest of Toronto s central business district in the heart of the southern Ontario region. The Airport is surrounded by a variety of industrial, commercial and residential land uses and is bound by a series of major highways and regional arterial roads. It is generally bounded by Highway 401 to the south, Etobicoke Creek to the west, Derry Road to the north and by Airport Road and Highway 427 to the east.

19 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 6 The general location of Toronto Pearson relative to the surrounding municipalities is shown on Figure 2.2. Figure 2.2 General Location of Toronto Pearson The area of land within the current operational boundary of Toronto Pearson covers 1,867 ha (4,613 acres) and encompasses airside facilities, passenger and cargo terminals, parking, access roads, business aviation, and aviation support facilities. Figure 2.3 presents a satellite image of the airport. The developing watersheds upstream of Toronto Pearson has a significant influence on the flood water flows experienced in the Etobicoke Creek and Spring Creek watercourses that flow through Toronto Pearson. While this geographic feature will not have an impact on the climate parameters, future climate changes may have a significant influence on the creek flood flows.

20 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 7 Figure 2.3 Aerial Photo of Toronto Pearson Due to its favourable location within Canada, Toronto Pearson not only serves those visiting or living within south-central Ontario, but also the growing number of passengers using the Airport as a connecting point for onward journeys. Toronto s central gateway location means that an estimated 60 per cent of North America s population is within a 90-minute flight from Toronto Pearson Jurisdictional Considerations The Protocol requires jurisdictions that are applicable to the infrastructure be identified during the completion of Step 1. These jurisdictions are provided to comply with the Protocol and provide a frame of reference for readers not familiar with the governance structure. More specific laws, regulations and guidelines are identified during completion of Step 2 of the protocol. Toronto Pearson is a federally owned facility that is leased to the GTAA. Because the land is federally owned and airports are federally regulated, the facility falls exclusively under federal jurisdiction. However, not every activity that the airport authority engages in is exempt from provincial legislation. The airport authority may be subject to provincial regulation if it does not impair a vital aspect of the federal undertaking. The following federal legislation has a direct impact on activities of the GTAA at Toronto Pearson: Aeronautical Act and regulations; Navigation Protection Act; Fisheries Act;

21 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 8 Canadian Environmental Assessment Act (CEAA); Canadian Environmental Protection Act (CEPA); Transportation of Dangerous Goods Act; Workplace Hazardous Materials Information System (WHMIS); Canadian Aviation Regulations (CAR); and National Fire Code (NFC). Figure 2.4 Toronto Pearson Jurisdictional Map The following is a description of other relevant authorities and their relationship with GTAA. Provincial Government the province does not have any jurisdiction over GTAA. However, Highway 401 abuts the southerly airport property and Highway 427 abuts the easterly property limit; City of Toronto a portion of Toronto Pearson Airport is within City of Toronto. However, the City of Toronto does not have any legal jurisdiction over GTAA; Region of Peel a representative from Peel Region is a member of GTAA Board of Directors. Derry Road abuts the northerly property limit and there are regional water and wastewater municipal services that traverse the airport property. Toronto Pearson water supply is derived from Peel s Lake Based Water System and the wastewater generated at the airport is disposed in Peel s Etobicoke Creek Trunk Sanitary Sewer System;

22 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 9 Region of York a representative from York Region is a member of GTAA Board of Directors; Region of Durham a representative from Durham Region is a member of GTAA Board of Directors; Region of Halton a representative from Halton Region is a member of GTAA Board of Directors; City of Mississauga a large portion of Toronto Pearson is located within City of Mississauga. However, the City of Mississauga does not have any legal jurisdiction over GTAA; and, Toronto & Region Conservation Authority Etobicoke Creek and Spring Creek both flow through Toronto Pearson Airport and a portion of the airport drains to Mimico Creek. However, TRCA does not have any jurisdiction over GTAA General Description of Infrastructure at Toronto Pearson The following provides a general overview of the infrastructure at Toronto Pearson. Airside Facilities Runways Taxiways and ramps Aprons and aircraft manoeuvring areas Central de-icing facility Toronto Area Control Centre Passenger Terminals Terminal 1 Terminal 3 Infield Terminal

23 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 10 Groundside Transportation Access, Circulation and Parking Above-ground parking surfaces and parking structures Roadways Bridges Tunnels Elevated automated people mover (LINK) Airside and Inter-Terminal Busing Facility and Bus Maintenance Facility Airport Support Facilities GTAA Administration Building Aircraft maintenance Airport security fencing Transport Canada/Peel Regional Police Building Fire and emergency training facilities Wildlife control centre Cogeneration plant Central workshops and stores Central Utilities Plant Various compounds

24 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 11 Air Cargo and Air Carrier Support Facilities Flight kitchens and catering Fuel Tank Farm and re-fuelling facilities Aircraft maintenance hangers and facilities Aircraft waste handling facilities Drainage & Stormwater Management Facilities Catch basins, inlet structures and collection system Storm sewers Culverts Open ditches Stormwater management facilities surface and underground facilities Water quality monitoring equipment Aviation Navigational and Communication Aids Air traffic control tower Toronto Area Control Centre (ACC) Glide Path equipment Localizer equipment Doppler Very High Frequency Omni-Directional Range/Distance Measurement equipment (DVOR/DME) Terminal Surveillance Radar (TSR) Airport Surface Detection equipment (ASDE) Non-directional beacons (NDB) Electronic and visual landing aids Runway and taxiway lighting Runway and taxiway markings Runway and taxiway signage Approach and landing lighting and systems

25 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 12 Business Aviation Area Several hangars Fuelling facilities Fixed base operators Communications Main computer rooms and telecommunication closets Fibre optic, copper and coaxial cables Security system (cameras, doors, intercoms, etc.) Water and Wastewater Potable water supply Fire fighting water supply Wastewater collection and disposal Pumping stations Electrical Power Supply and Distribution Main power feeders Switchyards Load modules Distribution system Control and data acquisition systems Heating and Air Conditioning Heating systems Air conditioning systems

26 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Study Area Climate The climate surrounding Toronto Pearson is typically described as humid continental with warm, humid summers and cold winters. There are four distinct seasons. Accumulating snow can fall any time from November until mid-april. The area is under the influence of the Great Lakes and can experience lakeaffect snow. The summer months are characterized by long stretches of humid weather. Precipitation is fairly evenly distributed throughout the year, but summer is usually the wettest season, the bulk falling during thunderstorms. Generally speaking, spring and summer temperatures range from 15 C to 25 C. During winter months, the average daytime temperature, with the exception of January, the coldest month, hovers just slightly below freezing. The average yearly precipitation is about 793 mm, with an average annual snowfall of about 115 cm. Table 2-1 provides climate normals from Environment Canada for the period The climate normal is referenced instead of the normal because the latter was not readily available during the early stages of this study, and as a result the data was used for the climate analysis. Table 2-1 Toronto Climate Normals ( ) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year Temperature Daily Average ( C) Daily Maximum ( C) Daily Minimum ( C) Extreme Maximum ( C) Extreme Minimum ( C) Precipitation Rainfall (mm) Snowfall (cm) Precipitation (mm) Average Snow Depth (cm) Snow Depth at Month-end (cm) Extreme Daily Rainfall (mm) Extreme Daily Snowfall (cm) Extreme Daily Precipitation (mm) Extreme Snow Depth (cm) Days With Maximum Temperature > 0 C Measurable Rainfall Measurable Snowfall Measurable Precipitation Source: Environment Canada

27 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 14 The climate analysis and projections component of the study are included as Appendix A of this report Time Frames Used for Analysis This study includes an assessment of the vulnerabilities of the stormwater facilities to current climate for existing conditions and to future climate change at the 2050 time horizon Historical The time frame used for assessment for representation of historical climate data is the period This 30-year period matches the most recent climate normal period readily available from Environment Canada during the time the climate analysis was completed. The climate normals were not made readily available in time to be included in this study. Figure 2.5, Figure 2.6 and Figure 2.7 below display the average temperature, extreme temperature, and precipitation at Toronto Pearson for the period This period of time does not exactly coincide with the historical time period, but the graphs were readily available from the City of Toronto Climate Drivers Study 2012 and clearly show the trends for average temperature, precipitation and wind. Figure 2.5 Average Temperature at Pearson Airport ( )

28 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 15 Figure 2.6 Extreme Temperature Pearson Airport ( ) Figure 2.7 Precipitation at Pearson Airport ( )

29 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 16 Figure 2.8 Gust Winds at Pearson Airport ( ) Future The time frame used for future projections was the 30-year period of 2041 to 2070, or more commonly expressed as the 2050s. Assessment of vulnerability beyond this horizon was not completed in consideration of the design life of the subject infrastructure without the undertaking of significant reconstruction or rehabilitation efforts. The level of uncertainty associated with future climate projections also increases significantly beyond the middle of this century, which would potentially call into question the utility of the results. The estimated design life of the infrastructure systems are provided in Table 2-2. Table 2-2 Design Life of Infrastructure Systems System Administration/Operation Surface Detention Storage Inlet/Outlet Structures Mechanical Systems Embankments Underground Concrete Tanks (Structural) Electric Power Supply Control and Monitoring Systems Communications Safety Systems Design Life years for physical structures Indefinite for personnel, procedures, and records Indefinite 80 years (civil) 50 years > 100 years 80 years 30 years 20 years 10 years 10 years

30 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 17 The systems noted above which have anticipated design lives of 30 years or less will require significant regular upgrades to maintain their serviceability. GTAA has been adequately maintaining these facilities. However, there will be significant maintenance required in the future as the facilities approach the mid point of their anticipated design lives Assess Data Sufficiency Infrastructure Data There were no identified data gaps at this step of the study Climate Data The overall intent of the climate analysis and projections component of this study was to use readily available information to the extent possible. Appendix A contains the climate analysis and projections used in this vulnerability assessment. Much of that climate information has been sourced through the TRCA Vulnerability Assessment study for its two large dams. All assumptions made for the climate related component of this study, along with the rationale used to support those assumptions are also contained in Appendix A.

31 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Data Gathering and Sufficiency Figure 3.1 Data Gathering and Sufficiency Process Flowchart 3.1. Overview The objective of the second step is to identify the specific features of the infrastructure to be considered in the assessment as well as the applicable climate information. In this step, data was acquired from the multiple sources identified in Step 1. The acquired data was then assessed for sufficiency Stormwater Facility Infrastructure General Infrastructure Components A general list of the major infrastructure systems associated with the Stormwater Facilities and their breakdown into individual components is provided in Table 3-1. It is noted that each stormwater facility has its own unique infrastructure components and not all components listed in Table 3-1 are associated with every stormwater facility.

32 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 19 Table 3-1 Typical Stormwater Facility Infrastructure Inventory System Component Administration/Operation Personnel (maintenance/inspection) Procedures (maintenance/inspection) Emergency procedures Access to facility Access on-site Records Detention Basin Reinforced concrete tank Dry storage pond Facility building (structure only) Inlet/Outlet Structures Inlet Ditch Diversion Diversion bypass outlet Outlet Concrete weir Sanitary connection Mechanical Systems Oil/water separator Interior actuators Exterior actuators Pumps HVAC Potable water line Sluice gate valve Electric Power Supply Electrical panel Lighting Backup power Control and Monitoring Gas detection system Systems PLC/SCADA system Fire alarm Level indicators Facility alarms (Active 8 System) Communications Phone line Two-way radio Cellular phone Safety Systems Berm Administration/Operation The administration and operations were broken into seven components; personnel (maintenance/ inspection), procedures (maintenance/inspection), emergency procedures, access to facility, on-site access and records. The personnel include the GTAA employees responsible for the management, operation, and maintenance of the stormwater facilities. The ability of personnel to safely and effectively operate the infrastructure during severe weather is important to the operation of the stormwater facilities as a complete system.

33 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 20 Records refer to all hard copies and controlled/original electronically stored documents relating to the operation of the infrastructure. Operating procedures refer to all procedures related to the operation of the stormwater infrastructure, including standard operating procedures and procedures for operation during emergencies. Figure 3.2 Access to electrical system and detention tank for the Aeroquay Facility Detention Basins The sub-components of detention basins are either dry surface ponds and/or underground storage tanks. The majority of the stormwater facilities have dry surface facilities, but Aeroquay, Carlingview and Moore Creek facilities have underground reinforced concrete storage tanks.

34 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 21 Figure 3.3 View of SWM6 stormwater detention pond (typical of dry detention ponds). Figure 3.4 View of Pond 2 stormwater detention pond (similar to Pond 4)

35 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 22 Figure 3.5 View of Aeroquay Facility s underground storage tank Inlet/Outlet Structures All of the stormwater facilities have inlets and outlets. Inlets structures consist of storm sewers, ditches or diversion structures. Outlet structures consist of storm sewers, sanitary sewers, bypass structures and overflow weirs.

36 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 23 Figure 3.6 Metal weir overflow plates in Cell 1 of the Moore Creek Facility Figure 3.7 Outlet from WM4A

37 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 24 Figure 3.8 Cargo diversion chamber bypass in Moore Creek Facility Mechanical Systems Mechanical components include oil/water separators, pumps, piping, sluice gate valves, HVAC and actuators. The mechanical equipment for some stormwater facilities are below ground or in a controlled environment. Some mechanical equipment is outside and exposed to the elements of weather.

38 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 25 Figure 3.9 Sluice gate for the SWM4 detention pond Figure 3.10 Exterior sluice gate control at Moore Creek Facility

39 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 26 Figure 3.11 Oil/water skimmer in the Aeroquay Facility Embankments Most stormwater facilities are constructed considering the surrounding topography and sited in a relatively low-lying area. However, in order to provide the necessary storage volume, some facilities have earthern berms or embankments.

40 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 27 Electric Power Supply Figure 3.12 The north face of the electrical and instrumentation control building for Moore Creek Facility Figure 3.13 Electrical and instrumentation control panel in the Moore Creek Facility electrical building

41 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 28 Control and Monitoring Systems Figure 3.14 Level indicator electronics in the Moore Creek Facility electrical and instrumental control building Figure 3.15 Gas detector electronics in Moore Creek Facility electrical building

42 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 29 Figure 3.16 Gas detector inside Moore Creek Facility tank Communications Communications consist of three main components; land-based telephone, cellular, and two-way radio. Safety Systems The safety system is broken down into three components; fencing, platforms, and security fences. Fences are used principally to restrict the entrance to the airside. Platforms are used for worker access to the facility or its operating equipment.

43 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 30 Figure 3.17 View of berm at Juliet Pond Sources of information for infrastructure data included the following documents: Stormwater Management Master Plan LBPIA Operations Manual for the Carlingview Stormwater Management Facility Jan. 1999; Carlingview Environmental Management Facilities, O&M Manual, 2007; Carlingview Stormwater Facility Maintenance Procedures AMMS Etobicoke Creek Stormwater Control Facility Operations and Maintenance Manual 1 and 2, and Mechanical Maintenance Manual; LBPIA Facility Operations Manual for the Etobicoke Creek Stormwater Control Facility Jan (online); Etobicoke Stormwater Facility Maintenance Procedures AMMS Moore Creek Stormwater Facility Instrumentation Maintenance Manual 1 and 2, and Mechanical Maintenance Manual; Moore Creek SWF Electrical Manual; Moore Stormwater Facility Maintenance Procedures AMMS GTAA Aeroquay Stormwater Management Facility Operations and Maintenance Manual Vol 1&2 March 2003; Active 8 System O&M Manual; Aeroquay Stormwater Facility Maintenance Procedures AMMS WM4 Operation and Maintenance Manual GTAA Stormwater Facilities Automatic Control Programs Control Narrative April 2007 Stormwater SCADA System O&M Manual, April 2009 Fuel, Gas, Sanitary, Storm, Fire and Water Services; Reduced Record Drawings, 2008 Specific Stormwater Pond Drawings

44 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Infrastructure of Interest Figure 3.18 delineates the location of stormwater facilities throughout Toronto Pearson. A brief description of each facility follows: Figure 3.18 Locations of Toronto Pearson Stormwater Facilities Note: Boeing Stormsewer does not exist and is not part of the stormwater facilities at Toronto Pearson.

45 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 32 Carlingview Stormwater Facility This facility is located east of Highway 427, constructed underground, under a parking lot. The facility was initially constructed in 1996 and expanded in It consists of reinforced concrete storage tanks with a total 17,000m 3 of capacity for stormwater quality and erosion control purposes. The stormwater facility also provides fuel, oil and grease removal facilities. The contributing drainage area is ha. The design criteria used for sizing the underground tank was the capture and storage of runoff volume from a 25 mm rainfall event from within the catchment area. The runoff that drains to the Carlingview SWM Facility originates from the old Terminal 2, Terminal 2 apron area and the fuel tank farm. The facility discharges to a trunk storm sewer which outlets to Mimico Creek. Runoff in excess of the storage capacity by-passes the facility and discharges directly to a sanitary sewer. A general overview of the facility is provided in Figure The location of the facility within the Toronto Pearson is provided in Figure Aeroquay Crescent Stormwater Facility This facility was constructed underground and consists of an underground reinforced concrete storage tank with a volume of 7,000m 3 to provide stormwater quality and erosion control. It was constructed in The ha contributing drainage includes the Terminal 1 Building and parking garage area. The design criteria used for sizing this underground tank volume was the capture and storage of runoff volume from a 25 mm rainfall event from within the catchment area. The facility discharges to a trunk storm sewer which outlets to Mimico Creek. Runoff in excess of the storage capacity by-passes the facility and discharges directly to Mimico Creek. A quick-connect connection was recently retro-fitted that allows contaminated water to be easily extracted from the facility and disposed elsewhere. A general overview of the facility is provided in Figure The location of the facility within the Toronto Pearson is provided in Figure SWM16 Facility This facility consists of a dry surface facility with storage volume 11,240m 3 to provide stormwater quantity and erosion control. It was constructed in The contributing drainage area is ha. The catchment area includes the area between South Perimeter Road and the ends of Runways 24L and 24R. The design criteria used for sizing this surface pond was the runoff volume from a 25 mm rainfall for water quality and erosion control. The 100-year design storm was used for sizing the quantity control portion of the facility. A general overview of the facility is provided in Figure The location of the facility within the Toronto Pearson is provided in Figure 3.18.

46 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 33 Figure 3.19 Carlingview Stormwater Facility, Aeroquay Stormwater Facility and SWM16 Carlingview Stormwater Facility Aeroquay Stormwater Facility SWM16 Pond Stormwater Pond 6B, Pond 2, and Pond 4 After the GTAA took over responsibility for Highway 409 west of Highway 427, the highway was widened. These SWM facilities were constructed in 1998 and 1999 to control the stormwater quantity, quality and erosion potential of runoff into Mimico Creek. The associated contributing drainage area is ha. A SWM facility is located in Area 6B with a storage volume of 11,220m 3 to treat combined runoff from Area 6A and 6B. That facility is sized for water quality, and erosion control (25 mm rainfall event) as well as stormwater quantity control (100-year design storm). The balance of quantity control storage is provided in two of the four quadrants of the Highway 409 and Highway 427 interchange. The combined volumes for Pond 2 and Pond 4 is 10,620m 3. A general overview of the facility is provided in Figure The location of the facility within the Toronto Pearson is provided in Figure 3.18.

47 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 34 Figure 3.20 Stormwater Pond 6B, Pond 2, and Pond 4 Pond 4 Pond 2 Pond 6B Etobicoke Creek Stormwater Facility This facility was initially constructed in 1998 and expanded in The facility has been sized to receive all stormwater runoff from the new terminal and apron area, the central de-icing facilities, and parts of the south infield. This represents a total drainage area of ha. The new terminal and apron areas account for ha of the total drainage area. The facility has a storage volume of 56,300m 3 that provides dry surface detention storage with an artificial wetland for polishing. The design criterion used for sizing the Etobicoke Creek Stormwater Facility was the storage of the first 25 mm of runoff volume from impervious areas. All stormwater flow in excess of this is diverted directly to Etobicoke Creek. The sewer systems entering the facility are equipped with stormceptors. The Etobicoke Creek Stormwater Facility holds storm runoff as required when concentrations of glycol exceed the discharge standards of Etobicoke Creek. A connection is provided to the sanitary sewer for conveying stormwater with high concentrations of glycol to the Region of Peel Lakeview Treatment Plant. A general overview of the facility is provided in Figure The location of the facility within Toronto Pearson is provided in Figure A14 Facility This facility is a dry facility with a storage volume of 4,920m 3, providing stormwater quality and erosion control for a contributing drainage area of 48.8 ha. It was constructed in The design criteria used

48 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 35 for sizing the facility was the capture and storage of runoff volume from a 25 mm rainfall event. All stormwater flows in excess of this event are discharged to Etobicoke Creek, after cresting an overflow spillway. The area that contributes runoff to Stormwater Facility A14 comprises a portion of Runway 06R/24L, related airfield development, and a portion of the Airside Service Road. A general overview of the facility is provided in Figure The location of the facility within the Toronto Pearson is provided in Figure Figure 3.21 Etobicoke Creek Facility and A14 Etobicoke Creek Stormwater Facility A14 Moore Creek Stormwater Facility and Spring Creek Surface Facility This facility provides storage for the first 25 mm of rainfall volume for water quality and erosion control purposes. It was constructed in ,000m 3 is provided by the underground tanks, and 42,000m 3 provided in two separate surface detention ponds (Moore Creek and Spring Creek storage ponds). The underground tank consists of three storage cells. Stormwater enters the first cell, then cascades to the second and third, until the capacity is reached (12.5 mm of rainfall). Rainfall in excess of 12.5 mm bypasses the tank via a set of overflow weirs, and flows first into the Moore Creek surface detention pond (total capacity 26,000m 3 ). Overflow from this pond flows to the Spring Creek surface detention pond, which has a capacity of 16,000m 3. Rainfall in excess of 25 mm will bypass the storage facilities and flow directly to Spring Creek. A weir spillway and emergency spillway are provided to relieve flows in excess of the Spring Creek surface pond capacity.

49 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 36 These stormwater facilities capture and control the runoff generated from the Terminal 3 and apron area, parts of Runway 33R/15L, parts of Taxiway Hotel and the air cargo facilities. The total contributing drainage area is ha. A general overview of the facility is provided in Figure The location of the facility within the Toronto Pearson is provided in Figure Figure 3.22 Moore Creek Stormwater Facility and Spring Creek Storage Pond Moore Creek Stormwater Pond Moore Creek Stormwater Facility Spring Creek Storage Pond SWM4 Facility This facility consists of a dry type surface stormwater quantity control facility with a storage volume of 26,700m 3. It was constructed in The contributing drainage area is ha. The SWM facility controls the outflow to meet downstream storm sewer capacity constraints of 2.0m 3 /s (as per agreement with City of Mississauga). SWM4 was designed for the 100-year design storm event. In addition, 10,000m 3 of surface storage capacity is provided in the grassed area between existing Runway 06-24R and Taxiway D5. SWM4 does not have any freeboard associated with its storage capacity and any flow in excess of the 100-year design storm will cause ponding and flooding in the surrounding area. Figure 3.23 depicts the flooding that occurred on July 8, 2013 in the vicinity of SWM 4.

50 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 37 Figure 3.23 July 8, 2013 flooding in vicinity of SWM 4 The area that contributes runoff to SWM4 Facility comprises the GTAA administrative and maintenance facilities, including GTAA corporate administrative offices, a fire hall, Peel Regional Police/Transport Canada building, central workshops, hangar, aprons, parking lots and ground maintenance buildings. Figure 3.24 depicts the flooding that occurred on July 8, 2013 in the vicinity of Convair Drive.

51 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 38 Figure 3.24 July 8, 2013 flooding in vicinity of SWM5 SWM 5 Facility This facility consists of a dry type surface stormwater quantity control facility with a storage volume of 4,900m 3. It was constructed in The contributing drainage area is 19.4 ha. SWM5 was designed for the 100-year design storm event. The SWM facility controls the outflow to meet downstream storm sewer capacity constraints of 0.80m 3 /s. SWM5 does not have any freeboard associated with its storage capacity and any flow in excess of the 100-year design storm will cause ponding and flooding in the surrounding area. The area that contributes runoff to SWM5 Facility comprises the Airside Service Road and the groundside service road. A general overview of the facility is provided in Figure The location of the facility within Toronto Pearson is provided in Figure SWM6 Facility This facility consists of a dry type surface stormwater quantity control facility with a storage volume of 24,800m 3. It was constructed in The contributing drainage area is ha. SWM6 was designed for the 100-year design storm event. The SWM facility controls the outflow to meet downstream storm sewer capacity constraints of 0.7m 3 /s. SWM6 does not have any freeboard associated with its storage capacity and any flow in excess of the 100-year design storm will cause ponding and flooding in the surrounding area.

52 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 39 The area that contributes runoff to SWM6 Facility comprises Runway 06R/24L, taxiways, related airfield development, and the Airside Service Road. A general overview of the facility is provided in Figure The location of the facility within the Toronto Pearson is provided in Figure Figure 3.25 SWM4, SWM5, and SWM6 Facilities SWM4 SWM5 SWM6 A2 FedEx Facility This facility is a dry type surface facility with a storage volume of 6,500m 3, which provides stormwater quality and erosion control. It was constructed in It does not provide stormwater quantity control. The contributing drainage area is ha. The design criteria used for sizing the facility was the runoff volume from a 25 mm rainfall event. This stormwater facility essentially services the FedEx Distribution Facility and apron area. A general overview of the facility is provided in Figure This facility controls stormwater runoff from the business aviation facilities, Runway 15L approach area, and parts of Juliet. It was constructed in The ultimate drainage area is ha. The WM4A Stormwater Facility is for stormwater quality control and treats runoff from a 25 mm rainfall event.

53 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 40 WM4A Facility The WM4A Stormwater facility provides a storage volume of 19,400 m 3. All stormwater flow in excess of this event is discharged to Spring Creek, after cresting an overflow spillway. A general overview of the facility is provided in Figure The location of the facility within the Toronto Pearson is provided in Figure Figure 3.26 WM4A, FedEx Pond and Juliet Pond WM4A FedEx Pond Juliet Pond Juliet Stormwater Pond This facility is a dry type surface facility with a storage volume of 4,500m 3, which provides stormwater quality and erosion control. It was constructed in All stormwater flows in excess of this event are discharged to Spring Creek, after cresting an overflow structure. It does not provide storm water quantity control. The contributing drainage area is ha. The catchment area includes the Menkes Site, Skeet Club and Apron area. The design criteria used for sizing the facility was the runoff volume from a 25 mm rainfall event. A general overview of the facility is provided in Figure The location of the facility within the Toronto Pearson is provided in Figure 3.18.

54 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Spring Creek Triple Cell Box Culvert Infrastructure General Infrastructure Components A breakdown of the Spring Creek Triple Cell Box Culvert into individual components is provided in Table 3-2. Table 3-2 Spring Creek Triple Cell Box Culvert Components System Administration/Operation Structural System Embankment Component Personnel (Maintenance/Inspection) Procedures (Inspection/Maintenance) Emergency Procedures Access to culvert On-site access Security Access - gate access Records Upstream concrete Apron Upstream rip-rap Downstream apron Downstream rip-rap Upstream wingwall Downstream wingwall Cell structures Expansion joints Construction joints Baffles (for fish migration) Parapet walls 1050 culvert inlet Embankment Administration/Operation The administration and operations were broken into seven components; personnel (maintenance/ inspection), procedures (maintenance/inspection), emergency procedures, access to facility, on-site access and records. The personnel include the GTAA employees responsible for the management, operation, and maintenance of Spring Creek Triple Cell box Culvert. The ability of personnel to safely and effectively operate the infrastructure during severe weather is important to the operation of the airport as a complete system. Records refer to all hard copies and controlled/original electronically stored documents related to the operation of the infrastructure.

55 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 42 Operating procedures refer to all procedures related to the operation of the culvert including standard operating procedures and procedures for operation during emergencies. Figure 3.27 Inlet of Spring Creek Triple Cell Box Culvert Figure 3.28 Looking upstream inside westernmost cell of Spring Creek Triple Cell Box Culvert

56 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 43 Figure 3.29 Channel downstream of Spring Creek Triple Cell Box Culvert Infrastructure of Interest Spring Creek Triple Cell Box Culvert This culvert is located on Spring Creek, directly downstream from Derry Road. It was originally constructed in 1969 to convey Spring Creek under Runway 05/23 and the Taxiway Hotel extension. The structure consists of three separate concrete box culverts in parallel. Each culvert is 5.1m wide by 3.05m high and was originally 450m long. In 2001 Spring Creek culvert was extended northerly by 115m to accommodate extension of Taxiway Juliet. In 2012 the northern part of the culvert was retrofitted to provide additional support to the north portal wing walls. The culvert was designed to convey the 100-year design storm. Recent hydraulic analysis of Spring Creek reveals that the Regional Storm exceeds the conveyance capacity of the structure and will overtop the embankment and Runway 05/23. A general overview of the facility is provided in Figure The location of the facility within the Toronto Pearson is provided in Figure 3.18.

57 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 44 Figure 3.30 Spring Creek Triple Cell Box Culvert overview Spring Creek Triple Cell Box Culvert 3.4. Climate Analysis Objectives The objectives of the climate analysis and projections portion of this study were to: Establish a set of climate parameters describing climatic and meteorological phenomena relevant to Toronto Pearson Airport; and, Establish a general probability for the occurrence of each phenomenon, both historically and in the future. The term historical is defined as comprising both the existing climate as well as climate from the recent past, while the term future is defined as representing the 2050s.

58 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Methodology The List of Climate Variables A list of climate variables was developed based on climate events and change factors identified in Appendix A of the Protocol as indicated below: High Temperature Heavy 5-Day Total Rainfall Lightning Low Temperature Winter Rain Hailstorm Heat Wave Freezing Rain Hurricane/Tropical Storm Cold Wave Ice Storm High Wind Extreme Diurnal Temperature Variability Heavy Snow Tornado Freeze Thaw Snow Accumulation Drought/Dry Period Heavy Rainfall Blowing Snow/Blizzard Heavy Fog Extreme Heavy Rainfall Rain (Frequency) Acid Rain Frost Wet Days Dust Storm It was recognized at the outset of this study that other recently completed climate change studies could provide suitable climate data for use in this study. Mr. David Lapp of Engineers Canada suggested some other PIEVC studies could provide reliable climate information. Using climate data and information from other studies, potentially could reduce or eliminate the need to generate new climate projections for the Toronto Pearson study. Climate data from four recently completed studies were scrutinized, with a view to deciding whether that data would be appropriate and adequate for the Toronto Pearson study: 1. National Engineering Vulnerability Assessment to Climate Change for Flood Control Dams, Toronto and Region Conservation Authority (TRCA), December Toronto s Future Weather & Climate Drivers Study, City of Toronto, December Climate Change Vulnerability Assessment for Culverts, City of Toronto, December Toronto Hydro-Electric System Public Infrastructure Engineering Vulnerability Assessment Study, TRCA Vulnerability Assessment to Climate Change for Flood Control Dams, 2009 The TRCA study was guided by the PIEVC Protocol and developed a list of climate parameters based on climate events and change factors included in Appendix A of the Protocol. The list was further developed and revised into a more comprehensive list based on climatic and meteorological phenomena deemed to be relevant to the geographic region (southwestern Ontario) and the region s known seasonal variability. Factors dictating the selection of climate parameters, and the indices used to express them, were based on data availability of several standard meteorologically-accepted parameters in consideration of both the historical/existing record as well as future projection model output. Justification for parameter selection was also based on the parameter s potential to present

59 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 46 vulnerability to the infrastructure and its components as a result of either an extreme or persistent occurrence. Information was retrieved from Environment Canada s Canadian Climate Normals, Climate Data Online (Environment Canada, 2008), the Ontario Node of the Canadian Atmospheric Hazards Network (Environment Canada, 2009) and the Canadian Daily Climate Data (CDCD V1.02) program (Environment Canada, 2007). For these data sources, Toronto Pearson weather station data was used. Future climate projections were analyzed using climate model outputs from Environment Canada s Canadian Climate Change Scenario Network (CCCSN) Scatter Plots (CCCSN, 2007b) and Bioclimate Profiles (CCCSN, 2007a), the Intergovernmental Panel on Climate Change (IPCC) 4th Assessment Report (AR4, 2007) Regional Climate Projections chapter, and scientific journal articles presenting regional and local projections and predictions. The exercise of calculating the probability of an event s occurrence (for both current and future) was already compiled in the TRCA report. A score between 0-7 was assigned to each parameter, as guided by the PIEVC Protocol. The TRCA study contained many of the climate parameters of interest to the GTAA for conducting the Toronto Pearson Vulnerability Assessment. The relevant climate analysis and projections component of TRCA large dams study is included in Appendix A of this current report. Appendix A is not a strict replication of the TRCA climate analysis and projection component, since modifications were made to various climate parameter definitions and climate parameters in addition to TRCA s study have been included in the Toronto Pearson study. Climate Specialists from Cole Engineering assisted in the development and modification of various climate parameters Toronto s Future Weather & Climate Drivers Study, 2011 The objective of the City of Toronto Weather & Climate Drivers Study was to better understand what currently influences Toronto s weather and climate. Once those influences were determined, it was necessary to know how those influences are likely to change and how severe the consequences are likely to be in the future. The City of Toronto was not content with relying exclusively on Global or Regional Climate Models (GCM or RCM) due to their coarseness of grid scale. In addition, the City wanted to use climate extremes rather than averages. The City s reasoning is that operation of critical infrastructure such as the electrical grid, water treatment plants, sewers and culverts, public transport and roads are sensitive to particular temperature and weather thresholds. Beyond these thresholds infrastructure may have reduced capacity or may not function at all. The City wanted to use local weather modeling at a much finer resolution, i.e. using 1x1 km gridded data, to include the influences of local features rather than 50x50 km coarse gridded data, "driven" by GCM/RCM model output. The study adopted a modelling approach using nested models. The results from the British Meteorological Office Hadley Centre climate model (HadCM3) were inputted into a medium resolution RCM (PRECIS) to provide results that were inputted into a fine resolution weather-climate model (FReSH). A present climate of was developed using the modelling approach, as well as a future climate of Climate projections were generated for Toronto Pearson, along with 35 other locations around the GTA.

60 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 47 The approach of adding a weather model to the climate model output to obtain more locally relevant future prediction forecasts was new and innovative when that project was conceived. The main climate parameters that were studied were: Temperature; Precipitation; Wind; and, Humidity Table 3-3 is extracted from the City of Toronto Climate Drivers Study. It summarizes Extreme Weather Events for the period These weather events are not specific to the Toronto area, but are interesting to recall and reflect upon. These weather events were not captured in the currently published Environment Canada s Climate Normals ( ). Table 3-3 Summary of Extreme Weather Events for Year Record Events 2000 Wettest summer in 53 years with 13% more precipitation than normal Driest growing season in 34 years; first ever heat alert; 14 nights with temperatures above 20 C (normal is 5 nights) Driest August at Pearson Airport since 1937; warmest summer in 63 years; fifth coldest Spring Rare mid-spring ice storm Pearson Airport used a month s supply of glycol de-icer in 24-hours Year without a summer; May rainfall in Hamilton set an all-time record; and another all-time record 409 mm rainfall was set at Trent University in July which was equivalent to 14 billion litres of water in 5 hours (a 200 year event) Warmest January 17 since 1840; January 22nd blizzard with whiteouts; warmest June ever; number of Toronto days greater than 30 C was 41 (normal is 14); August 19 storm washed out part of Finch Avenue tornadoes across Ontario (14 normal); record year of major storms; record one-day power demand of 27,005 MW due to summer heat Protracted January thaw; 2nd least snow cover ever in Toronto (half the normal amount); snowiest Valentine s Day ever; chunks of ice fell from CN Tower; 2-3 times the normal number of hot days in the summer; record latest-in-season string of +30 C days around Thanksgiving Toronto s 3rd snowiest winter ever; record for highest summer rainfall rd rainiest February in 70 years; Hamilton had a 100-year storm; one of the wettest summers on record; tornados hit Vaughan-Woodbridge area in late August; an unusually mild and storm-free November in Toronto Downtown had a record "no snow" for the first time ever first snow-free November at Pearson Airport since Toronto's earliest ever official heat wave (June 19-21) Also Three 1 in 100-year storms in Toronto in less than 13 years: July 2000, August 2005, July 2013.

61 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 48 Some of the findings from the Climate Drivers Study follow: On average in , warmer annual average temperatures of 4.4 o C are expected. For seasonal averages winter temperatures are projected to increase by 5.7 o C and summer temperatures by 3.8 o C. Extreme daily maximum temperatures are projected to increase by 7.6 o C, but extreme daily minimum temperatures are projected to also rise by 13 o C (i.e., becomes less cold). Less snow and more rain in the winters (26 fewer snow days per year) and fewer rainstorm events per year are anticipated. However, the model predicts more extreme rainstorms and marked rainfall increases in July (80%+) and in August (50%+). Precipitation - Snow and Rain Less snow and more rain in the winter 26 fewer snow days per year, 9 less in December Slightly more precipitation (snow plus rainfall) overall Marked rainfall increases in July (80%) and August (50%) Extreme rainstorm events, fewer in number but more extreme Precipitation amounts are projected to remain similar to the present for about 8 months of the year but increase markedly in July and August (with 80% and 50% increases caused by extra rainfall over present values respectively). The number of days with rain greater than 25 mm is projected to decrease while the total precipitation is projected to increase. This means that the future will see a smaller number of storm events but on average each will produce a higher amount of precipitation than occurs today. Hot and Cold Temperatures Average annual temperatures increase by 4.4 C. The projected average winter temperature increase by 5.7 C. The projected average summer temperature increase by 3.8 C. The extreme daily minimum temperature "becomes less cold" by 13 C. The extreme daily maximum temperature "becomes warmer" by 7.6 C. Winds Wind speeds will be unchanged on average Maximum wind speeds will be reduced This suggests more vertical and less horizontal motion developing stronger convective storms (in summer) meaning that there will be more clear skies and calmer periods between storms.

62 Difference in Amount Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 49 Figure 3.31 summarizes the changes expected to occur between the period and the period Figure 3.31 Projected Change in Monthly Average Rainfall and Snowfall Source: Toronto s Future Weather & Climate Drivers Study, Pearson Airport: Change to Rainfall (mm) Snowfall (cm) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month

63 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 50 Table 3-4 Projected Future Weather Changes Compared to Recent Weather Source: Toronto s Future Weather & Climate Drivers Study, 2011

64 Difference in Wind Speed in km/h Amount in mm Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 51 Figure 3.32 Projected Extreme Daily Rainfall Source: Toronto s Future Weather & Climate Drivers Study, Pearson Airport: Extreme DAILY Rainfall Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month Figure 3.33 Projected Change in Wind Source: Toronto s Future Weather & Climate Drivers Study, 2011 Pearson Airport: Change to Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month Average Speed (km/h) Max Hourly Speed Max Gust Speed

65 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Toronto s Climate Change Vulnerability Assessment for Culverts, 2011 The climate analysis and projections required for that study followed a similar methodology as developed for the TRCA PIEVC assessment of the two large dams. The two large dams and the culverts are located in the Toronto area, and the historical data analyzed for the TRCA study remains valid, and therefore the City of Toronto utilized a similar approach. While the TRCA study used a review of numerous predictions for the future projections, the City of Toronto study used climate projection data from the City s Climate Drivers Study. Where required projection data was not available from the Climate Drivers Study, the results from the TRCA s PIEVC study for the two large dams was used Toronto HydroElectric System Public Infrastructure Engineering Vulnerability Assessment Study, 2012 Toronto Hydro-Electrical System Limited (THESL) used parts of the PIEVC protocol to complete a study they referred to as a pilot case study. The purpose of that study was to evaluate the impact of existing climate on select parts of their distribution and transmission infrastructure. The study differed from typical PIEVC studies because it focused only on the effect of the current climate and did not incorporate a future climate projection to assess how a changing climate may impact their infrastructure. In addition, the Toronto Hydro-Electric study did not proceed beyond Step 3 of the PIEVC Protocol process. The existing climate was defined by a list of parameters that were suspected to have a negative impact on the infrastructure. For the most part, these parameters were adapted from the TRCA study of the two large dams. Threshold definitions were changed in some cases to better reflect the sensitivities of distribution and transmission infrastructure. For example, the availability of temperature related design capacities prompted a change in definition of the high temperature threshold. These electrical specific thresholds would not be as well suited for stormwater facilities (Toronto Pearson study). A different approach was also taken in assigning probability scores that would not be compatible with the Toronto Pearson stormwater infrastructure. The time period used to determine probability scores was the service life of the infrastructure, while the Toronto Pearson study used a constant period of one year. Since the THESL study did not include a projection of the future climate and their thresholds had limited applicability to stormwater facilities, it was decided that it would be better to use a more fulsome source such as the TRCA study Discussion Regarding Available Climate Data & Projections The deliberations on sourcing the climate information and data involved meetings with the TRCA and City of Toronto staff responsible for the previous studies. This allowed for a clearer understanding of the climate data and assisted in the decision making process. While the climate data from the City s Climate Driver study is appealing, it was generally considered that there could be additional costs associated with generating specific data for climate parameters that were not readily available from the study (see long list of climate variables in Section ). On the other hand, the probability scoring required by the PIEVC Protocol had been completed in the TRCA study and seemed appropriate. The TRCA climate

66 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 53 data set seemed to offer all the climate parameters that the GTAA was interested in evaluating and there would likely not be any further cost associated with accessing the information. One other point that influenced the final decision to use the TRCA climate data was the methodology and approach used in the PIEVC Protocol. Specifically, the Protocol lends itself to a step-by-step process that if, in the future, the GTAA decides to update the vulnerability assessment and use a different climate data set, another data set could readily be substituted for the original data set, at the time of study update. Therefore, the primary source of climate data was the TRCA Vulnerability Assessment to Climate Change for Flood Control Dams. Data and information from the City of Toronto Climate Drivers study was also used in this study, as it provided some specific data related to climate parameters that were useful in Step 4 (Engineering Analysis). It is noteworthy that two significant meteorological events occurred during the course of undertaking this vulnerability assessment study. An extreme rainfall event occurred on July 8, 2013 resulting in a total rainfall amount of 126mm falling in about seven hours at Toronto Pearson. Working collaboratively with the City of Toronto, City of Mississauga, and the Region of Peel, Cole Engineering analyzed real time data from rainfall gauges deployed throughout the area. Figure 3.34 shows the total rainfall contours resulting from that storm. Toronto Pearson received the greatest amount of total rainfall from that storm event. Figure 3.35 and Figure 3.36 show the rainfall intensity contours for the 60 minute and 120 minute durations. These figures show that the Toronto Pearson vicinity received the highest rainfall intensity. Analysis has concluded that storm was a 1:100-year event. Toronto Pearson sustained considerable flooding throughout the airport and damages are still being remedied.

67 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 54 Figure 3.34 July 8, 2013 Rainfall Total Depth

68 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 55 Figure 3.35 July 8, 2013 Maximum 60 Minute Intensity

69 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 56 Figure 3.36 July 8, 2013 Maximum 120 Minute Intensity

70 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 57 The second significant event commenced on December 22, 2013 when two freezing rain storms hit Southern Ontario over three days, resulting in an ice storm covering the Greater Toronto Area. The steady dose of freezing rain across much of Southern Ontario turned roads and sidewalks into skating rinks, cut power to hundreds of thousands of people, and played havoc with holiday plans at one of the busiest travel times of the year. Toronto Pearson realized flight delays and cancelations. Ground crews worked under extreme weather conditions to continue operations.

71 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Process of Probability Scoring The probability scoring process is outlined in Appendix A and follows the same process used for the PIEVC based vulnerability assessment of flood control dams completed by the TRCA, Several other recent PIEVC Vulnerability Assessments have also used the same process (adapted from the TRCA study). Table 3-5 summarizes the climate parameters used in this study and the associated probabilities for existing and future climate. Table 3-5 Summary of Climate Parameters and Associated Probabilities Category Climate Parameter GTAA Climate Probabilities Parameter Definitions Ex. 'P' Fu. 'P' Projection Source Temperature High Temperature Day(s) with a max. temp exceeding 35 C 4 5 TRCA PIEVC Study Low Temperature Day(s) with a min. temp below -30 C 3 2 TRCA PIEVC Study Heat Wave Three or more consecutive days >32 C 4 5 TRCA PIEVC Study Cold Wave Diurnal Temperature Variability Three or more consecutive days with min temp. <-20 C and max temp. < -10 C 3 2 TRCA PIEVC Study Daily temp. variation of more than 25 C 3 2 TRCA PIEVC Study Freeze/Thaw 85 or more freeze-thaw cycles within one year 4 2 TRCA PIEVC Study Frost 175 or more frost days within one year 4 3 Literature Review Heavy Fog 15 or more hours with visibility <0km within one year 4 4 TRCA PIEVC Study Wind High Wind/Downburst 8 or more days with max. winds of >=63km/hr in one year 4 4 TRCA PIEVC Study Tornado Vortex extending upward from the earth's surface at least as far as cloud base (occurring near site) 1 1 TRCA PIEVC Study Precipitation Extreme Heavy Rainfall Days with rainfall > 125mm 1 2 TRCA PIEVC Study Heavy Rainfall Days with rainfall > 50mm 4 5 TRCA PIEVC Study Rain (Frequency) 23 or more days of >10mm of rain within one year 4 5 Literature Review Heavy 5 day total Rainfall A five day period receiving >100mm of rainfall 2 3 TRCA PIEVC Study Winter Rain/Rain-on- Snow Greater than 25mm of rain falling during January, February and March 4 4 TRCA PIEVC Study Freezing Rain 9 or more days with freezing rain in one year 4 6 TRCA PIEVC Study Ice Storm Severe freezing rain events 2 3 TRCA PIEVC Study Snow Storm/Blizzard 8 or more days with blowing snow in one year 4 4 TRCA PIEVC Study Heavy Snowfall Days with snowfall >10cm 6 6 TRCA PIEVC Study

72 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 59 Category Climate Parameter GTAA Climate Probabilities Parameter Definitions Ex. 'P' Fu. 'P' Projection Source Snow Accumulation 5 or more consecutive days with a snow depth of >30cm 6 5 TRCA PIEVC Study Hailstorm Days with precipitation falling as ice particles (dia. >5mm) 5 5 TRCA PIEVC Study Acid Rain Precipitation with ph of <4 2 2 Literature Review Wet Days 112 or more days with measureable rainfall >0.2mm in one year 4 5 Literature Review Other Lightning lightning strikes on the airport property within one year 3 3 TRCA PIEVC Study Hurricane/Tropical Storms Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 1 2 TRCA PIEVC Study Drought/Dry Periods 10 consecutive days with <0.2mm of precipitation 5 6 TRCA PIEVC Study Dust Storm Visibility <1 km for more than an hour 2 2 Literature Review Other Potential Changes that May Affect the Infrastructure Changes in use pattern that increase or decrease the capacity of the infrastructure are: Upstream and/or downstream development and land use change; and sedimentation of the stormwater facilities. Operation and maintenance practices that increase or decrease the capacity or useful life of the infrastructure are: Pre-emptive maintenance for concrete structures such as crack repair, spalling concrete repair; Pre-emptive maintenance for steel work such as sandblasting, reinforcement and re-painting; Lubrication of mechanical components for gates and controls; Inspection and replacement of wear components in mechanical and electrical equipment; and, Periodic inspection by maintenance personnel on a defined schedule. Changes in management policy that affect the load pattern on the infrastructure are: Changes in stormwater facility operation protocol and procedures. Changes in laws, regulations, and standards that affect the load pattern on the infrastructure are: Possible changes to the regulatory flood requirements or stormwater management criteria.

73 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Assessment of Data Sufficiency Infrastructure Data The amount of infrastructure data gathered was sufficient in this step, and appeared to be of good quality and accuracy. No data gaps were identified at this stage. The prioritized referenced documentation for the infrastructure data is provided in Table 3-6 with general priority given to the most recent documentation/data. Table 3-6 Prioritized Reference Documentation for Infrastructure Data Priority Referenced Documentation 1 Engineering Drawings 2 Design Reports 3 Operations, Maintenance records 4 Maintenance Information including Equipment Manuals and Inspection Reports Climate Data The data gaps, data quality, data accuracy, application of trends, reliability of selected climate models, and the reliability of climate change assumptions are all discussed in Appendix A. 4.0 Risk Assessment 4.1. Overview The objective of the third step is to identify the interactions between the infrastructure, the climate, and any other factors that could lead to vulnerability. This includes identifying specific infrastructure components, specific climate change parameter values, and specific performance goals. An engineering vulnerability exists when the total load effects on infrastructure exceed the total capacity to withstand them, while meeting the desired performance criteria. Where the total loads or effects do not exceed the total capacity, adaptive capacity exists. Step 3 of the PIEVC Protocol involved the identification of infrastructure components which are likely to be sensitive to changes in specific climate parameters. This step focuses on qualitative assessments as a means of prioritizing more detailed Evaluation Assessment of Engineering Analysis in Step 4 of the Protocol. Professional judgment and experience was used to determine the likely effect of individual climate events on individual components of the infrastructure. To achieve this objective, the Protocol uses an assessment matrix process to assign an estimated probability and an estimated severity to each potential interaction. Figure 4.1 provides a flowchart of the process of Step 3. Risk Assessment Methodology: The default method uses a scale of 0 to 7 to establish the probability of each of the climate infrastructure interactions occurring and the severity

74 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 61 resulting from the interaction. The product of the probability and severity of the interaction is used to develop a risk value for each of the climate infrastructure interactions. Risk Tolerance Thresholds: Once the risks are calculated, tolerance thresholds have to be identified. The risk tolerance thresholds determine what risk range can be classified as low, medium, or high risk. Risk Ranks: The relationships between the infrastructure and its environment are prioritized to identify areas where vulnerability to existing climate and to potential future climate change exists. Components from the risk interactions that are identified as medium are considered further analysis in the Engineering Analysis in Step 4. These components will be the ones that show some vulnerability but that cannot be confirmed at this stage to be highly vulnerable or insensitive to a changing climate. Data Sufficiency: It is determined if assessment of specific components require data that is not currently available. If such a scenario is encountered, we will re-examine Step 1 and/or Step 2 to obtain sufficient data, if possible, to continue the assessment. If the data is not available and obtaining it is out of the scope of the Study then such findings will be documented in the recommendations made in Step 5. Figure 4.1 Risk Assessment Process Flowchart

75 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Risk Assessment Methodology To determine a value for the risk associated with an interaction between an infrastructure component and a climate related event, the protocol dictates that the probability of the event occurring is multiplied by the severity of the impact to determine the overall risk value. To develop a risk value for each infrastructure-climate interaction, scales of 0 7 are established for the probability of the interactions occurring and the severity resulting from the interaction. The Protocol provides three alternate methods; A, B, and C (shown in Table 4-1) for using the probability scale. Method A was selected for this assessment. For the severity scale, the Protocol provides two methods; D and E as shown in Table 4-2 Method E was selected for this assessment. Methods A and E were selected as they were based on non-numerical criteria, which merged well with Step 3 since it is more qualitative in nature than quantitative. It was felt that the numerical scales provided in the alternative methods would require a level of precision and accuracy that could not be supported by available data regarding climate probability and impact severity.

76 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 63 Table 4-1 Probability Scale Factors Scale Probability Method A Method B Method C 0 Negligible or not applicable <0.1% or <0.1/20 Negligible or not applicable 1 Improbable/Highly Unlikely 5% or 1/20 Improbable 1: Remote 20% or 4/20 Remote 1: Occasional 35% or 7/20 Occasional 1: Moderate/Possible 50% or 10/20 Moderate 1: Often 65% or 13/20 Probable 1:100 6 Probable 80% or 16/20 Frequent 1:10 7 Certain/Highly Probable >95% or >19/20 Continuous 1:1 Table 4-2 Severity Scale Factors Scale Method D Method E Severity 0 No effect Negligible or Not Applicable 1 Measurable Very Low/Unlikely/Rare/Measurable Change 2 Minor Low/Seldom/Marginal/Change in Serviceability 3 Moderate Occasional Loss of Some Capability 4 Major Moderate Loss of Some Capacity 5 Serious Likely Regular/Loss of Capacity and Loss of Some Function 6 Hazardous Major/Likely/Critical/Loss of Function 7 Catastrophic Extreme/Frequent/Continuous/Loss of Asset

77 Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Using a Spreadsheet to Document the Risk Assessment A spreadsheet was developed that comprised a header row for relevant climate events. The title columns consist of relevant infrastructure systems and components, and their performance response to relevant climate change effects. Two separate matrices were established using the above noted spreadsheet for each facility to include both the existing and future risks. A sample spreadsheet for a stormwater facility is shown in Table 4-3. The complete matrices for all stormwater facilities and the Spring Creek Triple Cell Box Culvert are included in Appendix B. Table 4-3 Sample Risk Assessment Matrix Temperature Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Infrastructure Component Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consec utive days >32 C Administration/ Y/N P S R Y/N P S R Y/N P S R Operation Component Example Detention Basin Y/N P S R Y/N P S R Y/N P S R Component Example Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Component Example 4.4. Populating Title Columns of the Spreadsheets The title column of the matrices was populated with the list of infrastructure systems and components. Performance response categories were established based on the most likely response of an infrastructure component to contemplated climate events. The performance response categories were based on professional judgment and experience. It is important to identify the performance response categories as it defines the associated risk. For example, the occurrence of a high temperature event for personnel is not a risk. However, its effect on personnel not being able to respond in emergency situations is a risk. The performance category for the above mentioned example would be emergency response, which is important to the analysis as it defines the risk.

78 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 65 The following performance response categories were considered in Table 4-4: Table 4-4 Performance Response Considerations Performance Response Keyword Potential Infrastructure Response Structural Design (Design) Safety Load carrying capacity Overturning Sliding Fracture Fatigue Serviceability Deflection Permanent deformation Cracking and deformation Vibration Foundation design considerations Infrastructure Functionality (Functionality) Level of effective capacity (short, medium, long term) Equipment (component selection, design, process and capacity considerations) Infrastructure performance (performance) Level of service, serviceability, reliability Materials performance Watershed, Surface Water, and Groundwater Erosion along watercourse (Environment) Erosion scour of associated/supporting earthworks Sediment transport Channel realignment/meandering Change in water quantity Change in water quality (water quality) Change in water resources demands Change in groundwater recharge Change in thermal characteristics of water resource Operations and/or Maintenance Structural aspects Equipment aspects Functionality and effective capacity Emergency Response (Emergencies) Storm, flood, ice, water damage Insurance Considerations (Insurance) Rates Policy Considerations (Policies) Codes Public sector policy Guidelines Intergovernmental communications Social Effects (Social Effects) Relevant social effects

79 Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 66 A summary of the identified performance response considerations for the corresponding infrastructure components for the selected stormwater facilities and Spring Creek Triple cell box culvert is provided in Table 4-5. Table 4-5 Performance Response Considerations for Stormwater Facilities and Spring Creek Culvert Infrastructure Response Consideration Infrastructure Component 4.5. Yes/No Analysis The next step of the process is to assess the potential for adverse interactions between each climate parameter and each infrastructure component. At this stage of the process, the team is not assessing the magnitude of the risk. Rather, this is a second stage of screening. If the team determines that there can be an adverse interaction between a climatic parameter and an infrastructure component, the interaction is retained within the process for further risk analysis. If the team determines that there may be no material adverse impact, the interaction is eliminated from further risk assessment analysis Populating Header Rows of the Spreadsheets The header row of the matrices was populated with the list of climate parameters provided in Section Definitions for each of the climate parameters were also provided below the header row. Under each climate parameter, title sub-columns were created as follows: Y/N (Yes/No). This field is marked Y if there is an expected interaction between the infrastructure component and the climate effect, and N if not. Relevant or irrelevant for further consideration. P (Climate Probability Scale Factor). This value reflects the probability of the respected climate variable occurring within the time horizon of the vulnerability assessment. S (Response Severity Scale Factor). This value reflects the expected severity of the interaction between the climate phenomena and the infrastructure component. R (Risk Score). This is calculated as P multiplied by S. This risk value is used to determine how the interaction will be assessed in the next steps of the Protocol. The value of R is also helpful in determining the priority of recommended actions, but is not to be solely relied on.

80 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Using Assessment Spreadsheet to Calculate the Risk for Each Relevant Interaction Instead of assessing the severity scale factor of each performance response for individual infrastructure components, all the performance responses that were relevant were check marked, and only one severity scale factor was applied. The severity scale factor that was applied was based on judgment of the performance response that was most critical to the individual infrastructure-climate interaction. The cells under the P column were populated as described in Section 3 (Section 3.4, Climate Parameters) and Appendix A, under the Probability Scoring subsections for each climate parameter. A summary table of the probability scores is provided in Table 3-6. The cells under the S column were populated using engineering judgment from GTAA staff with specific knowledge of the infrastructure. The Risk for each infrastructure-climate interaction was calculated using the following equation: R = P x S Where: R = Risk P = Probability of the interaction S = Severity of the interaction The final risk assessment matrices are included in Appendix B Evaluating Potential Cumulative Effects The cumulative impact of combining or sequencing climate events was evaluated to assess the possibility of these combined events yielding a higher compound event. However, since the information available for the individual climate events was limited, it was identified early on that it would be even more difficult to obtain information on a combination of the individual climate events, especially in a future scenario. Nevertheless, it is noted that the severities would increase for combined events. The following climate parameters that were evaluated may be considered as combined/sequenced events: Heat Wave consecutive days of high temperature Cold Wave consecutive days of low temperature Extreme Diurnal Temperature Variability difference between extreme high and low temperature Freeze Thaw sequence of diurnal temperatures varying between above freezing and below Heavy 5-Day Total Rainfall consecutive days of heavy rain Winter Rain combination of heavy rain and low temperatures, frozen ground or snow on ground Freezing Rain combination of rain and below freezing temperatures Ice Storm combination of heavy rain, below freezing temperatures Blowing Snow combination of snow (on ground or falling) and high wind

81 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 68 Snow Accumulation sequence of heavy snow events Hail normally occurs in combination with heavy rain and high wind Hurricane/Tropical Storm combination of heavy rain and high wind 4.9. Risk Assessment Workshop This evaluation was complemented by a Risk Assessment Workshop which was held at the FESTI facility at Toronto Pearson on October 9, This gathering brought together representatives from the Engineers Canada, Transport Canada, Toronto and Region Conservation Authority, Credit Valley Conservation, City of Mississauga, Region of Peel and others. The workshop consisted of an overview presentation by Derek Gray of GTAA, David Lapp of Engineers Canada on the PIEVC Protocol and Ryan Ness of TRCA on the climate information. All participants were provided with a workbook, which included the workshop agenda, selected presentation slides, scale factors, and the risk assessment matrices. The workshop participants were split into two groups, and each group had the task of assessing Spring Creek Triple Box Culvert. That facility was deemed a Special Case and it was considered worthy of further assessment by workshop participants. Due to time limitations, each group worked only on the assigned infrastructure components of the matrix. A list of participants is provided in Table 4-6. Table 4-6 Workshop Attendees Name Affiliation Project Role/Job Title Derek Gray GTAA Manager Environmental Services Chris Stewart GTAA Manager, Airside Infrastructure and Engineering Daphne De Souza GTAA Senior Environmental Officer Paul Wajda GTAA Senior Municipal Engineer Mike Riseborough GTAA Director Aviation Infrastructure, Energy and Environment Steve Thomas GTAA Senior Environmental Officer Marcos Zambrano GTAA Environmental Technician Randy McGill GTAA Associate Director, Corporate Sustainability Marc St Jean GTAA Associate Director, Business Performance, Aviation Services David Lapp Engineers Canada Manager, Professional Practice Rebecca Earl Transport Canada Communications Advisor Chandra Sharma TRCA Watershed Specialist, Etobicoke-Mimico & Senior Manager, Climate Programs Don Haley TRCA Ryan Ness TRCA Manager Water Resources CVC Lincoln Kan City of Mississauga Manager, Environmental Services Jeremy Blair City of Mississauga Storm Drainage Programming Engineer John Nemeth Shawn Taylor Jeff Hirvonen Region of Peel Dillon Alan Winter Cole Engineering Facilitator

82 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 69 The groups were constructed with the following considerations, where possible: Management and Operations staff were assigned to separate groups; Each group had a member who was well versed with the climate analysis; and, Each group had a moderator and a recorder Establish the GTAA s Risk Tolerance Thresholds The risk tolerance thresholds were reviewed, and are provided in Table 4-7. These thresholds are the same as those provided in the Protocol. While the Protocol provides default thresholds, it is important to note that they are not fixed. There was discussion around the possibility of altering these thresholds, however in the end it was decided that the thresholds suggested in the Protocol would be used. Upon review of the risk assessment, the thresholds appeared reasonable. Table 4-7 Risk Tolerance Thresholds Risk Range Threshold Response <12 Low Risk No immediate action necessary Medium Risk Action may be required Engineering Analysis may be required >36 High Risk Immediate action required Low risk interactions represent no immediate vulnerability. Based on professional judgment, the potential climate change vulnerability associated with the infrastructure component is very low. Therefore, no further action is necessary. Medium risk interactions characterize a potential vulnerability. Based on professional judgment, the potential climate change vulnerability associated with the infrastructure component does exist, and further engineering analysis may be necessary to provide a clear determination of the vulnerability. High risk interactions characterize an identified vulnerability. Based on professional judgment, the potential climate change vulnerability associated with the infrastructure component is identified, and immediate action may be required. As noted, the qualitative nature of the risk assessment process is based on engineering and professional judgment. The documented results represent a consensus amongst the workshop participants for a particular interaction. However, the initial discussion on a specific climate variable infrastructure component interaction would usually begin with some participants reflecting opinions of a lower severity and others a higher severity.

83 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Rank the Risks Complete and Comparison matrices are provided in Appendix B Each matrix includes the existing risk score, the future risk score, and the difference between the existing and future risk scores. Furthermore, all the medium risk interactions are highlighted in yellow. The low risk interactions are those that are not highlighted. No high risk interactions were identified in this assessment. A summary of the findings is provided in Table 4-8. Figure 4.2 shows graphically the ranking of facilities according to level of risk. Appendix C contains a full summary of the ranked risks according to each facility Assess Data Sufficiency Infrastructure Data Since Step 3 was more qualitative in nature, the data available for assessment use was sufficient, particularly where non-numerical, engineering and other professional judgment-based screening was applied Climate Data The historical climate analysis and future climate projections were conducted using data from the TRCA PIEVC study, as listed in Table A-4. Toronto Pearson weather station data were used. All assumptions are clearly stated within Appendix A and the TRCA PIEVC Study Final Report.

84 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Summary of Findings Table 4-8- Summary of Findings Total Infrastructure Risk Interactions Carlingview Facility Moore Creek Facility Etobicoke Creek Facility Spring Creek Culvert Low Risk Interactions Medium Risk Interactions High Risk Interactions Flagged Interactions* Existing Future Existing Future Existing Future Existing Future Aeroquay Facility Existing Future Pond 2 Existing Future Pond 4 Existing Future SWM6 Pond Existing Future SWM4 Pond Existing Future WM4A Pond Existing Future Juliet Pond Existing Future B Pond Existing Future FedEx Pond Existing Future SWM5 Pond Existing Future SWM16 Pond Existing Future SWMA14 Pond Existing Future TOTAL Existing Future * Note: Flagged Interactions are when P=1 and R=7 and vice versa.

85 Existing Future Existing Future Existing Future Existing Future Existing Future Existing Future Existing Future Existing Future Existing Future Existing Future Existing Future Existing Future Existing Future Existing Future Existing Future Number of Interactions Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 72 Figure 4.2 Summary of Findings Carlingview Facility Moores Facility Etobicoke Creek Facility Spring Creek Culvert Total Interactions Low Risk Interactions Medium Risk Interactions High Risk Interactions Existing Risk Future Risk Aeroquay Facility Pond 4 Pond 2 SWM6 Pond SWM4 Pond WM4A Pond Juliet Pond 6B Pond FedEx Pond SWM5 Pond SWM16 Pond

86 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 73 The following points summarize the risk assessment findings for: The risk assessment identified 4378 interactions as low risk interactions for existing conditions and 4063 for future conditions. There were 1442 medium risk interactions identified for existing conditions and 1757 identified for future conditions. No interactions were identified as high risk for existing or future conditions. It was identified in the risk assessment that 457 interactions that were identified as low risk for the existing conditions, but which changed to medium risk for future conditions, as a result of climate change, based on current understandings. On the other hand, there were 142 interactions that were identified as medium risk for the existing conditions, but which decreased to a low risk score for future conditions, as a result of climate change, based on current understandings. The interaction between storage facility and heavy rain received the highest risk score for both existing and future conditions. The interactions with the greatest risk scores in ranked order are provided in Appendix C.

87 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Engineering Analysis 5.1. Overview The objective of the fourth step is to assess the impact on the infrastructure and its capacity from the projected climate change loads. This includes a focused engineering analysis on the relationships determined to have medium vulnerability to climate change in Step 3. Figure 5.1 Engineering Analysis Process Flowchart provides a visual of the Step 4 process. Figure 5.1 Engineering Analysis Process Flowchart When the infrastructure has insufficient capacity to withstand the loads placed on it, it is considered to be vulnerable; it is resilient when the capacity is sufficient. The total loading of the infrastructure is calculated by combining the existing loads and future loads from climate change and other factors, using the following formula: LT = LE + LC + LO, Where: LT is the projected total load on the infrastructure LE is the existing load on the infrastructure LC is the projected load on the infrastructure resulting from climate change LO is the projected load on the infrastructure resulting from other changes

88 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 75 The total capacity is calculated by combining the existing capacity with any changes in the future as the infrastructure matures, or as retrofits or upgrades provide additional capacity, using the following formula: CT = CE - CM + CA, Where: CT is the projected total capacity of the infrastructure CE is the existing capacity of the infrastructure CM is the projected change in infrastructure capacity as a result of age / use CA is the projected additional capacity of the infrastructure The total loading and total capacity can then be used to calculate important indices such as the Vulnerability Ratio (VR) and the Capacity Deficit (CD), as follows: Vulnerabilities occur when VR is greater than 1 and when VR is less than 1, the infrastructure component has adaptive capacity. The capacity deficit is the required amount of capacity that must be added to the infrastructure to mitigate the vulnerability Step 4 Engineering Analysis The infrastructure-climate interactions that scored a risk value between 12 and 36 in Step 3 were analysed further under this step. The analysis included a determination of the relationship between the loads placed under both existing and potential future conditions on the infrastructure and its capacity. The results of this step are provided in Table 5-6 and Table 5-7 located at the end of this chapter. These Engineering Analysis Tables consist of the following fields: Infrastructure Component: lists all components that are included in interactions with risk scores between 12 and 36. Climate Variable: lists all climate parameters corresponding to the infrastructure components that are included in interactions with risk scores between 12 and 36. Basis of Determination/Data Source: provides a definition, description, justification, or data source upon which the values in the cells are based upon. Existing, Climate, Other, and Total Loads Existing, Maturing, Additional and Total Capacities Vulnerability Capacity Deficit Comments/Data Sufficiency

89 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 76 A sample of the Engineering Analysis table is provided in three parts by Table 5-1, Table 5-2 and Table 5-3. Table 5-1 Sample Layout of the Engineering Analysis Part 1 Infrastructure Component Administration/Operations Personnel Climate Parameter Existing Load (L E) Calculation of Total Load (L T) Climate Load Timeframe L C Other Load L O Total Load L T = L E + Lc + L O High Temperature >0 n/a > 0.75 Basis of Determination/Data Source Day(s) with a max. temp exceeding 35 C Projected increase Probability increase from '4' to '5' Freezing Rain ~ >0 n/a >1.25 Basis of Determination/Data Source 9 or more days with freezing rain in one year Projected increase Probability increase from '4' to '6' Table 5-2 Sample Layout of the Engineering Analysis Part 2 Infrastructure Component Administration/Operations Climate Parameter Existing Capacity C E Calculation of Total Capacity (C T) Maturing Capacity C M Additional Capacity C A Total Capacity CT = C E - C M + C A Personnel High Temperature C E> L T n/a n/a C T> L T Basis of Determination/Data Source Engineering Judgement Engineering Judgement Freezing Rain C E> L T n/a n/a C T> L T Basis of Determination/Data Source Engineering Judgement Engineering Judgement Table 5-3 Sample Layout of the Engineering Analysis Part 3 Infrastructure Component Administration/Operations Personnel Climate Parameter Vulnerability (VR) V R = L T/C T Capacity Deficit (CD) C D = L T - C T High Temperature V R< 1 0 Basis of Determination/Data Source Engineering Judgement Engineering Judgement Freezing Rain V R< 1 0 Basis of Determination/Data Source Engineering Judgement Engineering Judgement Comments/Data Sufficiency Personnel may experience some discomfort but will likely still be able to perform their usual duties. Personnel will likely not be able to work under these conditions. Their regular duties will only be delayed.

90 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 77 The following sections provide more information on the parameters involved in this step of the Protocol Calculate the Existing Load (L E ) The existing load was based on the historic probabilities determined using the methods documented in Section 3, and applied in Section 4, Risk Assessment. The value of the existing load was the number of occurrences per year that corresponded to the historic probability determined for the interactions. If a specific value was available for the number of occurrences, then that value was considered the existing load. However, if no specific value was available then an estimate was provided by selecting the high value from the range of number of occurrences that corresponded to the probability score assigned to that interaction. As shown in the example provided in Table 5-1 the number of occurrences of high temperature, as defined in Appendix A is Hence, this value of 0.54 was used as the existing load. However, in the case of freezing rain, no specific value was provided from the analyses documented in Appendix A for the calculated number of occurrences. It was assigned a probability score of 4, and justified accordingly. In this case, the high value from the range of number of occurrences per year corresponding to a probability of 4 was used. Table A-1 shows that the range of number of occurrences per year corresponding to a probability of 4 is 0.25 to Therefore, the high value of the range i.e was used as the existing load. The high value of the range was selected since it represented the worst case scenario, which would result in a more conservative analysis Calculate the Climate Change Load (L C ) The intention of the climate change load parameter is to provide a numerical value that describes how a specific climate parameter changes as a result of climate change. Obtaining an exact value however proved to be difficult since available literature rarely projected information in a form that was compatible with the climate parameters used by this study. Previous PIEVC vulnerability assessments approached this difficulty by providing an estimate of the climate change load based on the future probability score assigned and its corresponding number of occurrences range. In this study however, no estimate of the climate change load was provided. Instead, the climate change load simply indicated whether the climate parameter would increase, decrease, or remain the same based on the climate analysis. If an exact value was available then it would be used, however no exact values were available from the climate analysis. This method was preferred over the previous method since it better represented the accuracy of the climate change load. The validity of the new method was deemed appropriate since it did not change the end result of the vulnerability ratios. As shown in the example provided in Table 5-1, the future probability score for high temperature was increased from the historic probability of a 4 to a 5. In this case, the climate change load was entered as >0 to demonstrate that high temperature events are expected to occur more frequently in the future. Similarly, if an event was expected to occur less frequently then the climate change load would be entered as <0 and as zero if no change in frequency is expected. The rationale for this methodology is consistent with the one used for the calculation of the existing load. The climate change loads for all the interactions included within Step 4 are provided in Table 5-6 and Table 5-7 located at the end of this chapter.

91 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Calculate Other Change Loads (L O ) Other change loads refer to the change in load arising from other change effects on the infrastructure. An example of an other change load would be the intensification or development of the area upstream of the Spring Creek Triple Cell box culvert. Since it was difficult to represent other change loads in the same manner, or unit, as the existing and climate change loads i.e. based on probabilities, generally no quantifiable value could be assigned Calculate the Total Load (T E ) The total loading of the infrastructure is calculated by combining the existing loads and future loads from climate change and other factors, using the following formula: LT = LE + LC + LO, Where: LT is the projected total load on the infrastructure LE is the existing load on the infrastructure LC is the projected load on the infrastructure resulting from climate change LO is the projected load on the infrastructure resulting from other changes As previously mentioned, the climate change load (LC) was generally not assigned an exact value in order to better represent its accuracy. For similar reasons, and out of necessity, a new method was developed to calculate the total load. The total load was calculated based on the future probability score assigned. Depending on whether the probability increased or decreased, the total load was stated to be greater or smaller than the appropriate occurrence range limit corresponding to the future probability score. As shown in Table 3-5, the probability of high temperature is expected to increase from a 4 to a 5. A probability score of 5 describes climate parameters that occur between 0.75 to 1.25 times per year. Based on this occurrence range, the total load was entered as >0.75. This method was thought to better reflect the accuracy of the total load and was deemed appropriate since it did not impact the final vulnerability ratios Calculate the Existing Capacity (C E ) Since it was difficult to represent the existing capacity of the components in the same manner or units as the existing and climate change loads i.e. based on probabilities, no quantifiable value could be assigned. A qualitative description was provided, where available, in the Engineering Analysis Tables. An example is provided in Table Calculate the Projected Change in Existing Capacity Arising from Aging/Use of the Infrastructure Similar to the existing capacities, it was difficult to represent the maturing capacities in the same manner or units as the existing and climate change loads i.e. based on probabilities. Therefore no

92 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 79 quantifiable value was assigned, instead a qualitative description was provided, where available. An example is provided in Table Calculate Additional Capacity The additional capacities were also difficult to quantify based on probabilities, which were used to quantify the loads. A qualitative description was provided, where available, in the Engineering Analysis Tables. An example is provided in Table Calculate the Projected Total Capacity (CT) The total capacity is calculated by combining the existing capacity with any changes in the future as the infrastructure matures, or as retrofits or upgrades provide additional capacity, using the following formula: CT = CE - CM + CA, Where: CT is the projected total capacity of the infrastructure CE is the existing capacity of the infrastructure CM is the projected change in infrastructure capacity as a result of age / use CA is the projected additional capacity of the infrastructure For this study, the total capacity was qualitatively described as being either greater or less than the total load, based on engineering judgment. The capacities were determined based on whether the infrastructure component is able to withstand the current climate conditions, and the response of the infrastructure to similar climate events that have occurred in the past, which are represented by the existing loads. The change in load was then compared to the existing load, and if the change was not considered to be relatively significant, then the infrastructure was determined to have adaptive capacity. Similarly, engineering judgment was applied to all the subsections that follow, where it has been indicated that a qualitative assessment was carried out. The qualitative assessment is provided in Table 5-6 and Table 5-7 located at the end of this chapter. Examples are provided in Table Calculate Vulnerability Ratio The Protocol dictates that the total loading and total capacity be used to calculate the Vulnerability Ratio (VR), as follows: Due to the difficulties in calculating the capacities of the infrastructure components, the vulnerability ratio could not be quantitatively calculated but was based largely on engineering judgment and understanding of the historic performance of the stormwater facilities and Spring Creek culvert.

93 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 80 Therefore, the vulnerability ratio was qualitatively assessed on being either greater or less than one. If the total capacity was estimated to be greater than the total load, then the vulnerability ratio was listed as less than one. A vulnerability ratio of less than one means that the infrastructure component was resilient and not vulnerable to the climate parameter. If the total capacity was estimated to be less than the total load, then the vulnerability ratio would be greater than one, indicating that vulnerability exists. Examples are provided in Table 5-3. The vulnerability ratios for all the interactions requiring engineering analysis are provided in Table 5-6and Table 5-7 located at the end of this chapter. Components that are considered vulnerable are summarized in Section Calculate Capacity Deficit The total loading and total capacity is also used to calculate the Capacity Deficit (CD), as follows: The Capacity Deficit is the difference between the total load and the total capacity. As discussed in Section 5.1 if the total load is greater than the total capacity, then there exists a capacity deficit. A capacity deficit always exists where there is vulnerability, i.e. a vulnerability ratio of greater than one. For this study, since there was no quantitative data for the total capacity, the capacity deficit could not be quantified. If the vulnerability ratio was greater than one, then the capacity deficit was stated to be greater than zero. The capacity deficit was given a value of zero if the vulnerability ratio was less than one. Examples are provided in Table Spring Creek Culvert In light of observations made during the July 8th 2013 extreme rainfall event and analysis available from hydraulic models, Spring Creek Culvert was suspected to have a higher risk associated with extreme heavy rainfalls than the risk matrices indicated. Regardless of the risk scoring, a decision was made to perform an engineering analysis on the culvert specifically for extreme rainfall events. It is noted that this diverges from typical protocol since the severity was only ranked a 5 and the future probability a 2. However, this divergence was deemed appropriate given the above stated information. As previously discussed, future climate projections anticipate rainfalls will be less frequent in general but will be more intense when they do occur. Consequently, extreme rainfall events may occur more frequently. For Spring Creek Culvert, this means that its capacity will likely be tested more often and in some cases exceeded. Spring Creek Culvert currently has sufficient design capacity to convey a 100-year design storm. Climate change projections indicate that the 100-year storm will likely occur more frequently in the future. IDF curves developed by Toronto s Future Weather and Climate Driver Study Volume 1 suggest that by the 2050 horizon the 100-year storm may occur every 25 years for short duration storms and every 5 years for long duration storms (see Figure 5.2) A frequency shift of this size would have a major impact on the performance of the culvert and would also introduce complications upstream.

94 Intensity (mm/hr) Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 81 Figure 5.2 Projected future IDF curves compared to existing 100-year curve IDF Comparison Current 100 yr Future 100 yr Future 25 yr Future 5 yr Future 100 yr Future 25 yr Future 5 yr Duration (hours) Source: Toronto s Future Weather and Climate Driver Study Volume 1 The hydraulic model developed for Spring Creek Culvert suggests that a 100-year storm will not exceed the capacity of the culvert or cause any significant problems upstream (refer to Figure 5.3). However, the 350-year storm is expected to exceed the capacity of the culvert, and although it is not expected to overtop the runway, it will likely overtop Derry Road upstream. In the future, the 100-year storm may be similar in intensity to the current 350-year storm and would consequently bear the above-mentioned risks.

95 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 82 Figure 5.3 Model Water Surface Profile of Spring Creek Culvert for the Existing 100 and 350-year Design Storms and the Regional Storm

96 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 83 It is also important to mention that the current hydraulic model assumes there are no obstructions in the culvert cells. During a 100-year storm, it is conceivable that debris from upstream could block one of these cells, resulting in a reduced capacity. Based on the analysis outlined above, Spring Creek Culvert was considered to be vulnerable to extreme heavy rainfall events in the future. This vulnerability is provided in Table 5-7 at the end of this chapter Assess Data Sufficiency In general, data was insufficient, to complete the engineering analysis in the specific method prescribed by the Protocol. In determining the climate load from the results of the Climate Analysis and Projections, the units were generally represented as a number of occurrences per year, or a probability of the event occurring in a given year. This definition allowed the calculation of the existing load and the climate load, however made the determination of the capacity of a component impossible in any meaningful, scientific way. For example, it is impossible to determine how many ice storms the wooden deck or the sluice gate at SWM 4 could withstand in a given year, or to put any number to the capacity of the electrical supply grid to a tornado. In light of the above, experience and professional engineering judgment was utilized to estimate whether or not the component was vulnerable to a singular occurrence or multiple occurrences of the climate parameter. This resulted in a qualitative assessment of vulnerability Evaluate Need for Additional Risk Assessment The need for reassessing the risk profile and conducting a revised risk assessment, i.e. repeating Step 3 was not identified Summary of Findings The complete results of the Engineering Analysis step can be found in Table 5-6 and Table 5-7. The analysis was completed according to the methods set out in the PIEVC Protocol. These methods do not explicitly consider the difference between existing or future vulnerability, but instead focus on whether the component is vulnerable to the net of the existing load, plus future climatic load. As a result, the assessment of vulnerability reflects only the future condition. However, in the case of the stormwater facilities, a review of the interactions assessed as vulnerable, or having a Vulnerability Ratio greater than one, indicated that these interactions would also be judged as vulnerable in the existing condition. This is not surprising, given the nature of the climate events and the lack of quantitative information with which to calculate the Total Capacity of virtually all of the infrastructure components considered. The Engineering Analysis generally resulted in a determination of the vulnerability of the infrastructure components to a single occurrence of the climate event, rather than the probability or frequency of the event. For example, personnel could be identified as vulnerable to a freezing rain event for both existing and future conditions, with no distinction made regarding whether personnel are more or less vulnerable in the future with an increased probability of freezing rain events, as there is no information available with which to determine whether a change in frequency would increase the vulnerability of the components.

97 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 84 The above notwithstanding, it was possible to make a determination of the difference between existing and future risk for the components and interactions identified as vulnerable by revisiting the results of the Risk Assessment completed in Step 3. In that assessment, the probability scores did change for some climate events, as shown in Table 3-5, from the existing to future conditions, and the associated risk scores changed as well. Based on a comparison of those existing and future risk scores for vulnerable components and interactions, the potential effect of climate change in modifying risk to those components could be determined. The following sections provide a summary of the results for the stormwater facilities. A total of 1699 medium risks were identified for all stormwater facilities combined. To reduce this number to a more manageable level, a condensed engineering analysis was performed by grouping facilities that had similar components. The condensed analysis considered 44 medium risk interactions. As mentioned in Section , the risk assessment results did not consider extreme heavy rainfall events a medium risk for water quantity control ponds. Given observations made during the recent July 8, 2013 rainfall event and the projected IDF curves in Figure 5.2 a decision was made using engineering judgement to consider this interaction as vulnerable. With the addition of this vulnerability, there were six interactions assessed to be vulnerable, i.e. they have a Vulnerability Ratio of greater than one. These vulnerabilities are provided in Table 5-4. Table 5-4 Vulnerable Components of the Stormwater Facilities (Vulnerability Ratio >1) Infrastructure Component Detention Basin Quality Ponds with bypass (Vegetated & Concrete Ponds) Quality Ponds without bypass (Vegetated & Underground Tanks) Quantity Ponds (Vegetated & Concrete Ponds) Climate Parameter Interaction Heavy Rainfall Heavy 5-Day Total Rainfall Heavy Rainfall Heavy 5-Day Total Rainfall Extreme Heavy Rainfall Comments The capacity of water quality stormwater facilities will be exceeded when rainfall exceeds the design capacity (25 mm). However, the facility will likely not lose functionality since it is equipped with a bypass. Functionality of the water quality component of stormwater facilities without a bypass may be impaired when rainfall exceeds the design capacity (25 mm) of the detention basin, due to reduced particle settling time and potential resuspension. The projected increase in intensity of rainfall events may result in the capacity of quantity ponds being exceeded. The effects of an exceeded capacity for some quantity ponds (e.g. SWM 4) are unclear and may have unfavorable consequences. Inlet/Outlet Structures All inlets, outlets, ditches, diversion chambers, weirs, etc. Extreme Heavy Rainfall The maximum capacity of these components will very likely be exceeded during an extreme heavy rainfall. In the future, these events are projected to occur more frequently.

98 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 85 For Spring Creek culvert, a total of 58 medium risks were identified. To reduce this number to a more manageable level, a condensed engineering analysis was performed by grouping similar components. The condensed analysis considered 15 medium risk interactions. There was only one interaction that was assessed to be vulnerable, i.e. a vulnerability ratio of greater than one. This vulnerability is provided in Table 5-5. Table 5-5 Vulnerable Components of Spring Creek Triple Cell Box Culvert (Vulnerability Ratio >1) Infrastructure Component Structural System The culvert Climate Parameter Interaction Extreme Heavy Rainfall Comments Projected increases in the intensity and frequency of extreme heavy rainfalls may result in the culvert s capacity being exceeded more frequently, and while Runway will likely not overtop during the future 100-year design storm, Derry Road upstream of the culvert may overtop Complete Engineering Analysis Tables The condensed engineering analysis tables for the stormwater facilities and Spring Creek culvert are provided in Table 5-6 and Table 5-7 below.

99 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 86 Table 5-6 Engineering Analysis for Stormwater Facilities Infrastructure Component Climate Parameter Calculation of Total Load (L T) Calculation of Total Capacity (C T) Vulnerability (VR) Administration/Operations Existing Load (L E) Climate Load Time frame L C Ot he r Lo ad L O Total Load L T = L E + Lc + L O Existing Capacit y C E Matu ring Capa city C M Additi onal Capaci ty C A Total Capacity CT = C E - C M + C A V R = L T/C T Capacity Deficit (CD) C D = L T - C T Comments/Data Sufficiency Personnel High Temperature >0 n/a > 0.75 C E> L T n/a n/a C T> L T V R< 1 0 Personnel may experience some discomfort but will likely still be able to perform their usual duties. Basis of Determination/ Data Source Day(s) with a max. temp exceeding 35 C Projected increase Probab ility increas e from '4' to '5' Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement Low Temperature <0 n/a < 0.1 C E> L T n/a n/a C T> L T V R< 1 0 Personnel may perform their duties slower than usual. In the future these Basis of Determination/ Day(s) with a min. Projected Engineering Engineering Engineering extreme cold events may occur less Data Source temp below -30 C decrease Judgement Judgement Judgement frequently and should not be an issue. Probab ility decrea se from '3' to '2' Engineer ing Judgem ent Heavy Rainfall >0 n/a >0.75 C E> L T n/a n/a C T> L T V R< 1 0 Personnel will not likely be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source Days with rainfall > 50mm Projected increase Probab ility increas e from '4' to '5' Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement Freezing Rain ~ >0 n/a >1.25 C E> L T n/a n/a C T> L T V R< 1 0 Personnel will not likely be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source 9 or more days with freezing rain in one year Projected increase Probab ility increas e from '4' to '6' Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement Ice Storm >0 n/a >0.1 C E> L T n/a n/a C T> L T V R< 1 0 Personnel will not likely be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source Severe Freezing Rain events Projected increase Probab ility increas e from '2' to '3' Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement Snow Storm / Blizzard ~ n/a ~0.5 C E> L T n/a n/a C T> L T V R< 1 0 Personnel will not likely be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source 8 or more days with blowing snow in one year No projectio n available Workin g assum ption Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement Snow Accumulation <0 n/a <1.25 C E> L T n/a n/a C T> L T V R< 1 0 Personnel may have difficulty finding any valves/hatches covered in snow that have not been sufficiently marked. Basis of Determination/ Data Source 5 or more consecutive days with a snow depth of >30cm Projected decrease Probab ility decrea se from '6' to '5' Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement

100 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 87 Hailstorm n/a 1.1 C E> L T n/a n/a C T> L T V R< 1 0 Personnel will not likely be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source Days with precipitation falling as ice particles (dia. > 5mm) No projectio n available Workin g assum ption Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement Personnel Lightning n/a C E> L T n/a n/a C T> L T V R< 1 0 Personnel will not likely be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source lightning strikes on the airport property within one year No projectio n available Workin g assum ption Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement Hurricane/Tropical Storm >0 n/a >0.05 C E> L T n/a n/a C T> L T V R< 1 0 Personnel will not likely be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source Cyclones of a tropical origin with sustained surface wind speeds >63km/hr Projected increase Probab ility increas e from '1' to '2' Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement Detention Basins Quantity Ponds (Vegetated & Concrete Ponds) Heavy Rainfall >0 n/a >0.75 C E> L T n/a n/a C T> L T V R< 1 0 The detention basin will likely not reach its maximum capacity (100yr). However, the basin will be partially full. Basis of Determination/ Data Source Heavy 5-Day Total Rainfall Basis of Determination/ Data Source Winter Rain/Rain-on Snow Days with rainfall >50mm Projected increase Probab ility increas e from '4' to '5' Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement >0 Projected increase n/a >0.1 C E> L T n/a n/a C T> L T Engineering Judgement V R< 1 Engineering Judgement 0 Engineering Judgement The detention basin will likely not reach its maximum capacity (100yr) during this event. However, the basin will be partially full. A five day period receiving >100mm of rainfall Probab ility increas e from '2' to '3' Engineer ing Judgem ent n/a 0.33 C E> L T n/a n/a C T> L T V R< 1 0 The rain will melt snow creating additional runoff. The detention basin will likely not reach its maximum capacity (100yr). Depending on the distribution of winter rain, the basin may contain a considerable amount of water.

101 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 88 Basis of Determination/ Data Source Greater than 25mm of rain falling during January, February and March Projected no change No change in probabi lity Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement Quantity Ponds (Vegetated & Concrete Ponds) Snow Accumulation <0 n/a <1.25 C E> L T n/a n/a C T> L T V R< 1 0 Snow accumulation contributes to snowmelt runoff during the spring. As Basis of Determination/ 5 or more Projected Probab Engineer Engineering Engineering Engineering currently designed, the detention basin Data Source consecutive days decrease ility ing Judgement Judgement Judgement will likely not reach its maximum with a snow depth decrea Judgem capacity (100 yr). A future decrease in of >30cm se from ent snow accumulation would have a '6' to '5' positive effect on the detention basins. Quality Ponds with bypass (Vegetated & Underground tanks) Heavy Snowfall n/a 2 C E> L T n/a n/a C T> L T V R< 1 0 The heavy snowfall may have an impact on scheduled maintenance/ inspection Basis of Determination/ Days with snowfall Limited Workin Engineer Engineering Engineering Engineering of the basins. However, since this type Data Source >10cm Projectio g ing Judgement Judgement Judgement of work is unlikely to be performed n assum Judgem during winter, the basins will not be Informati ption ent significantly impacted by a heavy on snowfall. Drought/Dry Periods >0 n/a >1.25 C E> L T n/a n/a C T> L T V R< 1 0 A drought may have a slight impact on the vegetation aspect of the basin. Basis of Determination/ 10 consecutive Projected Probab Engineer Engineering Engineering Engineering However, vegetation will likely have Data Source days with <0.2mm increase ility ing Judgement Judgement Judgement sufficient regular exposure to rainfall of precipitation increas Judgem since the total yearly precipitation is not e from ent expected to change significantly. '5' to '6' Heavy Rainfall >0 n/a >0.75 C E< L T n/a n/a C T< L T V R> 1 >0 The basin s maximum capacity (25 mm) will likely be exceeded more often. However, the treatment of the first 25 mm will likely be unaffected since the facility is equipped with a bypass. Basis of Determination/ Data Source Days with rainfall >50mm Projected increase Probab ility increas e from '4' to '5' Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement Rain (Frequency) ~ >0 n/a >0.75 C E> L T n/a n/a C T> L T V R< 1 0 The basin may be required to treat small rainfalls more frequently. This could Basis of Determination/ 23 or more days Projected Probab Engineer Engineering Engineering Engineering result in sediment deposits accumulating Data Source of >10mm of rain increase ility ing Judgement Judgement Judgement faster than anticipated. Current within one year increas Judgem maintenance practices will likely remain e from ent sufficient. '4' to '5' Heavy 5 Day Total Rainfall >0 n/a >0.1 C E< L T n/a n/a C T< L T V R> 1 >0 The basins maximum capacity (25 mm) may be exceeded by this event.

102 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 89 Basis of Determination/ Data Source Winter Rain/RainonSnow Basis of Determination/ Data Source A five day period receiving >100mm of rainfall Projected increase Probab ility increas e from '2' to '3' Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement However, the treatment of the first 25 mm will likely be unaffected since the facility is equipped with a bypass n/a 0.33 C E> L T n/a n/a C T> L T V R< 1 0 The rain will melt snow creating Greater than 25mm of rain falling during January, February and March Projected no change No change in probabi lity Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement additional runoff. The detention basin will likely not reach its maximum capacity (25mm). Depending on the distribution of winter rain, the basin may be partially full. Quality Ponds with bypass (Vegetated & Underground tanks) Snow Accumulation <0 n/a <1.25 C E> L T n/a n/a C T> L T V R< 1 0 Snow accumulation contributes to snowmelt runoff during the spring. The Basis of Determination/ 5 or more Projected Probab Engineer Engineering Engineering Engineering detention basins may approach or reach Data Source consecutive days decrease ility ing Judgement Judgement Judgement full capacity (25 mm). A future decrease with a snow depth decrea Judgem in snow accumulation would have a of >30cm se from ent positive effect on the detention basins. '6' to '5' Heavy Snowfall n/a 2 C E> L T n/a n/a C T> L T V R< 1 0 The heavy snowfall may have an impact on scheduled maintenance/ inspection Basis of Determination/ Days with snowfall Limited Workin Engineer Engineering Engineering Engineering of the basins. However, since this type Data Source >10cm Projectio g ing Judgement Judgement Judgement of work is not likely to be performed n assum Judgem during winter, the basins will not be Informati ption ent significantly impacted by a heavy on snowfall. Drought/Dry Periods >0 n/a >1.25 C E> L T n/a n/a C T> L T V R< 1 0 A drought may have a slight impact on the vegetation aspect of the basin. Basis of Determination/ 10 consecutive Projected Probab Engineer Engineering Engineering Engineering However, vegetation will likely have Data Source days with <0.2mm increase ility ing Judgement Judgement Judgement sufficient regular exposure to rainfall of precipitation increas Judgem since the total yearly precipitation is not e from ent expected to change significantly. '5' to '6' Quality Ponds without bypass (Vegetated) Heavy Rainfall >0 n/a >0.75 C E< L T n/a n/a C T< L T V R> 1 >0 The basin s maximum capacity (25 mm) will likely be exceeded more often. Reduced treatment functionality is likely Basis of Determination/ Data Source Days with rainfall >50mm Projected increase Probab ility increas e from '4' to '5' Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement as water flows through the facility. Where possible, a retrofitted bypass could mitigate this risk. Rain (Frequency) ~ >0 n/a >0.75 C E> L T n/a n/a C T> L T V R< 1 0 The basin may be required to treat small rainfalls more frequently. This could Basis of Determination/ 23 or more days Projected Probab Engineer Engineering Engineering Engineering result in sediment deposits accumulating Data Source of >10mm of rain increase ility ing Judgement Judgement Judgement faster than anticipated. Current within one year increas Judgem maintenance practices will likely remain e from ent sufficient. Heavy 5 Day Total Rainfall Basis of Determination/ Data Source Winter Rain/Rain-on Snow '4' to '5' >0 n/a >0.1 C E< L T n/a n/a C T< L T V R> 1 >0 The basin s maximum capacity (25 mm) may be exceeded by this event. Projected Probab Engineer Engineering Engineering Engineering Reduced treatment functionality is likely increase ility ing Judgement Judgement Judgement as water flows through the facility. increas Judgem Where possible, a retrofitted bypass e from ent could mitigate this risk. A five day period receiving >100mm of rainfall '2' to '3' n/a 0.33 C E> L T n/a n/a C T> L T V R< 1 0 The rain will melt snow creating additional runoff. The detention basin

103 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 90 Basis of Determination/ Data Source Greater than 25mm of rain falling during January, February and March Projected no change No change in probabi lity Engineer ing Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement will likely not reach its maximum capacity (25mm). Depending on the distribution of winter rain, the basin may be partially full. Quality Ponds without bypass (Vegetated) Snow Accumulation <0 n/a <1.25 C E> L T n/a n/a C T> L T V R< 1 0 Snow accumulation contributes to snowmelt runoff during the spring. The Basis of Determination/ 5 or more Projected Probab Engineer Engineering Engineering Engineering detention basins may approach or reach Data Source consecutive days decrease ility ing Judgement Judgement Judgement full capacity (25 mm). A future decrease with a snow depth decrea Judgem in snow accumulation would have a of >30cm se from ent positive effect on the detention basins. '6' to '5' Inlet/Outlet Structures All inlets, outlets, ditches, diversion chambers, weirs, etc Heavy Snowfall n/a 2 C E> L T n/a n/a C T> L T V R< 1 0 The heavy snowfall may have an impact on scheduled maintenance/ inspection Basis of Determination/ Days with snowfall Limited Workin Engineer Engineering Engineering Engineering of the basins. However, since this type Data Source >10cm Projectio g ing Judgement Judgement Judgement of work is not likely to be performed n assum Judgem during winter, the basins will not be Informati ption ent significantly impacted by a heavy on snowfall. Drought/Dry Periods >0 n/a >1.25 C E> L T n/a n/a C T> L T V R< 1 0 A drought may have a slight impact on the vegetation aspect of the basin. Basis of Determination/ 10 consecutive Projected Probab Engineer Engineering Engineering Engineering However, vegetation will likely have Data Source days with <0.2mm increase ility ing Judgement Judgement Judgement sufficient regular exposure to rainfall of precipitation increas Judgem since the total yearly precipitation is not e from ent expected to change significantly. '5' to '6' Extreme Heavy Rainfall >0 n/a >0.05 C E< L T n/a n/a C T< L T V R> 1 >0 The maximum capacity will very likely be exceeded during this event. In the future this is projected to occur more frequently. A separate study is currently underway to determine the consequences of this event. Basis of Determination/ Data Source Days with rainfall >125mm Projected increase Proba bility increa se from '1' to '2' Enginee ring Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement Heavy Rainfall >0 n/a >0.75 C E> L T n/a n/a C T> L T V R< 1 0 The maximum capacity will likely not be reached. The projected increase in Basis of Determination/ Days with rainfall Projected Engineering Engineering Engineering frequency of this event will likely have no Data Source >50mm increase Judgement Judgement Judgement significant impact. Heavy 5 Day Total Rainfall Proba bility increa se from '4' to '5' Enginee ring Judgem ent >0 n/a >0.1 C E> L T n/a n/a C T> L T V R< 1 0 The maximum capacity will likely not be reached. The projected increase in

104 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 91 All inlets, outlets, ditches, diversion chambers, weirs, etc. Mechanical Systems Oil/water separator, all actuators and pumps, ventilation system, valves, etc. Basis of Determination/ Data Source A five day period receiving >100mm of rainfall Projected increase Proba bility increa se from '2' to '3' Enginee ring Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement frequency of this event will likely have no significant impact. Rain (Frequency) ~ >0 n/a >0.75 C E> L T n/a n/a C T> L T V R< 1 0 The components will perform as designed. An increase in rain frequency Basis of Determination/ 23 or more days Projected Enginee Engineering Engineering Engineering may slightly accelerate deterioration of Data Source of >10mm of rain increase ring Judgement Judgement Judgement the infrastructure. However, current within one year Judgem inspection and maintenance practices ent will expose and replace damaged infrastructure as required. Proba bility increa se from '4' to '5' Snow Accumulation <0 n/a <1.25 C E> L T n/a n/a C T> L T V R< 1 0 Snow accumulation contributes to snowmelt runoff during the spring. The Basis of Determination/ 5 or more Projected Proba Enginee Engineering Engineering Engineering components capacity will likely not be Data Source consecutive days decrease bility ring Judgement Judgement Judgement reached. A future decrease in snow with a snow depth decrea Judgem accumulation would have a positive of >30cm se ent effect on these components. from '6' to '5' Winter Rain/RainonSnow Basis of Determination/ Data Source n/a 0.33 C E> L T n/a n/a C T> L T V R< 1 0 The rain will melt snow creating Greater than 25mm of rain falling during January, February and March Projected no change No chang e in proba bility Enginee ring Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement additional runoff. The components will likely not reach their full capacity. Depending on the distribution of winter rain, the components may be partial full at times. Freezing Rain ~ >0 n/a >1.25 C E> L T n/a n/a C T> L T V R< 1 0 The projected increase in freezing rain events may interfere with regular Basis of Determination/ 9 or more days Projected Proba Enginee Engineering Engineering Engineering maintenance/inspection schedules. The Data Source with freezing rain increase bility ring Judgement Judgement Judgement maintenance/inspection will only be in one year increa Judgem delayed. se ent from '4' to '6' Heavy Snowfall n/a 2 C E> L T n/a n/a C T> L T V R< 1 0 Heavy snowfall may interfere with regular maintenance/inspection Basis of Determination/ Days with snowfall Engineering Engineering Engineering schedules. The maintenance/inspection Data Source >10cm Judgement Judgement Judgement will only be delayed. Limited Projectio n Informati on Worki ng assum ption Enginee ring Judgem ent Low Temperature <0 n/a < 0.1 C E> L T n/a n/a C T> L T V R< 1 0 Low temperatures may reduce usability of some mechanical parts (e.g. manual exterior valves). Minor delays in maintenance/ inspection of exterior parts may also be expected. This event is projected to become less frequent and Basis of Determination/ Data Source Day(s) with a min. temp below -30 C Projected decrease Proba bility decrea se from '3' to '2' Enginee ring Judgem ent Engineering Judgement Engineering Judgement Engineering Judgement will likely have an insignificant impact on the overall functionality of the mechanic systems.

105 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 92 Low Temperature <0 n/a < 0.1 C E> L T n/a n/a C T> L T V R< 1 0 Low temperatures may reduce usability of some mechanical parts (e.g. manual Basis of Determination/ Day(s) with a min. Projected Proba Enginee Engineering Engineering Engineering exterior valves). Minor delays in Data Source temp below -30 C decrease bility ring Judgement Judgement Judgement maintenance/ inspection of exterior parts decrea Judgem may also be expected. This event is se ent projected to become less frequent and from will likely have an insignificant impact on '3' to the overall functionality of the mechanic '2' systems. Oil/water separator, all actuators and pumps, ventilation system, valves, etc. Freezing Rain ~ >0 n/a >1.25 C E> L T n/a n/a C T> L T V R< 1 0 The projected increase in freezing rain events may interfere with regular Basis of Determination/ 9 or more days Projected Proba Enginee Engineering Engineering Engineering maintenance/inspection schedules. The Data Source with freezing rain increase bility ring Judgement Judgement Judgement maintenance/inspection will only be in one year increa Judgem delayed. se ent from '4' to '6' Heavy Snowfall n/a 2 C E> L T n/a n/a C T> L T V R< 1 0 Heavy snowfall may interfere with regular maintenance/inspection Basis of Determination/ Days with snowfall Engineering Engineering Engineering schedules. The maintenance/inspection Data Source >10cm Judgement Judgement Judgement will only be delayed. Limited Projectio n Informati on Worki ng assum ption Enginee ring Judgem ent Blowing Snow / Blizzard n/a 7.8 C E> L T n/a n/a C T> L T V R< 1 0 A blizzard may interfere with regular maintenance/ inspection schedules. The Basis of Determination/ 8 or more days Engineering Engineering Engineering maintenance/ inspection will only be Data Source with blowing snow Judgement Judgement Judgement delayed. in one year Limited Projectio n Informati on Worki ng assum ption Enginee ring Judgem ent Snow Accumulation <0 n/a <1.25 C E> L T n/a n/a C T> L T V R< 1 0 Snow accumulation may interfere with maintenance/ inspection in areas which Basis of Determination/ 5 or more Projected Proba Enginee Engineering Engineering Engineering are not cleared of snow (e.g. WM4A Data Source consecutive days decrease bility ring Judgement Judgement Judgement valve). The maintenance/ inspection with a snow depth decrea Judgem would only be delayed, and could still be of >30cm se ent performed if necessary. from '6' to '5'

106 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 93 Table 5-7 Engineering Analysis for Spring Creek Culvert Infrastructure Component Administration/Operations Climate Parameter Calculation of Total Load (L T) Calculation of Total Capacity (C T) Vulnerability (VR) Existing Load (L E) Climate Load Other Timeframe L C Load L O Total Load L T = L E + Lc + L O Existing Capacity C E Maturing Capacity C M Additional Capacity C A Total Capacity CT = C E - C M + C A V R = L T/C T Capacity Deficit (CD) C D = L T - C T Comments/Data Sufficiency Personnel High Temperature >0 n/a > 0.75 C E> L T n/a n/a C T> L T V R< 1 0 Personnel may experience some discomfort but will likely still be able to perform their usual duties. Basis of Determination/ Data Source Day(s) with a max. temp exceeding 35 C Projected increase Probability increase from '4' to '5' Engineering Judgement Low Temperature <0 n/a < 0.1 C E> L T n/a n/a C T> L T V R< 1 0 Personnel may perform their duties slower than usual. In the future these extreme Basis of Determination/ Day(s) with a min. Projected Probability Engineering Engineering Engineering Engineering cold events may occur less frequently and Data Source temp below -30 C decrease decrease from Judgement Judgement Judgement Judgement should not be an issue. '3' to '2' Engineering Judgement Engineering Judgement Engineering Judgement Heavy Rainfall >0 n/a >0.75 C E> L T n/a n/a C T> L T V R< 1 0 Personnel will likely not be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source Days with rainfall >50mm Projected increase Probability increase from '4' to '5' Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Freezing Rain ~ >0 n/a >1.25 C E> L T n/a n/a C T> L T V R< 1 0 Personnel will likely not be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source 9 or more days with freezing rain in one year Projected increase Probability increase from '4' to '6' Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Ice Storm >0 n/a >0.1 C E> L T n/a n/a C T> L T V R< 1 0 Personnel will likely not be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source Severe Freezing Rain events Projected increase Probability increase from '2' to '3' Engineering Judgement Snow Storm/Blizzard ~ n/a ~0.5 C E> L T n/a n/a C T> L T V R< 1 0 Personnel will likely not be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source 8 or more days with blowing snow in one year No projection available Working assumption Engineering Judgement Snow Accumulation <0 n/a <1.25 C E> L T n/a n/a C T> L T V R< 1 0 Personnel may have difficulty finding any valves/hatches covered in snow that have not been sufficiently marked. Basis of Determination/ Data Source 5 or more consecutive days with a snow depth of >30cm Projected decrease Probability decrease from '6' to '5' Engineering Judgement Personnel Hailstorm n/a 1.1 C E> L T n/a n/a C T> L T V R< 1 0 Personnel will likely not be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source Days with precipitation falling as ice particles (dia. >5mm) No projection available Working assumption Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Lightning n/a C E> L T n/a n/a C T> L T V R< 1 0 Personnel will likely not be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source lightning strikes on the airport property within one year No projection available Working assumption Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement

107 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 94 Structural System Hurricane/Tropical Storm >0 n/a >0.05 C E> L T n/a n/a C T> L T V R< 1 0 Personnel will likely not be able to work under these conditions. Their regular duties will only be delayed. Basis of Determination/ Data Source Cyclones of a tropical origin with sustained surface wind speeds >63km/hr Projected increase Probability increase from '1' to '2' Engineering Judgement All rip rap Heavy Rainfall >0 n/a >0.75 C E> L T n/a n/a C T> L T V R< 1 0 The projected increase in storm intensity may result in rip-rap being disturbed more Basis of Determination/ Days with rainfall Projected Probability Engineering Engineering Engineering Engineering often than usual. Regular maintenance Data Source >50mm increase increase from Judgement Judgement Judgement Judgement would only have to be slightly adjusted to '4' to '5' accommodate for this. The culvert Heavy Rainfall >0 n/a >0.75 C E> L T n/a n/a C T> L T V R< 1 0 The culvert will likely not reach full capacity during a heavy rainfall. The projected Basis of Determination/ Days with rainfall Projected Probability Engineering Engineering Engineering Engineering increase in frequency of this event will Data Source >50mm increase increase from Judgement Judgement Judgement Judgement likely result in the culvert being partially '4' to '5' filled more frequently. Rain (Frequency) ~ >0 n/a >0.75 C E> L T n/a n/a C T> L T V R< 1 0 The culvert will perform as designed. An increase in rain frequency would likely have an insignificant impact on the culvert. Basis of Determination/ Data Source 23 or more days of >10mm of rain within one year Projected increase Probability increase from '4' to '5' Engineering Judgement Heavy 5 Day Total Rainfall >0 n/a >0.1 C E> L T n/a n/a C T> L T V R< 1 0 The maximum capacity will likely not be reached. The projected increase in Basis of Determination/ A five day period Projected Probability Engineering Engineering Engineering Engineering frequency of this event will likely result in Data Source receiving >100mm increase increase from Judgement Judgement Judgement Judgement the culvert being partially filled more of rainfall '2' to '3' frequently. Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement Snow Accumulation <0 n/a <1.25 C E> L T n/a n/a C T> L T V R< 1 0 Snow accumulation contributes to Basis of Determination/ Data Source 5 or more consecutive days with a snow depth of >30cm Projected decrease Probability decrease from '6' to '5' Engineering Judgement Engineering Judgement Engineering Judgement Engineering Judgement snowmelt runoff during the spring. The culvert's capacity will likely not be reached. A future decrease in snow accumulation would have a positive effect on this component.

108 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Recommendations 6.1. Overview The objective of Step 5 is to present limitations and recommendations on the observations and findings of the infrastructure vulnerability assessment in Steps 1 to 4. Figure 6.1 Recommendations Process Flowchart Relevant limitations include those associated with the following: Major assumptions; Available infrastructure information and sources; Available climate change information and sources; Available other change information and sources; Uncertainty and related concepts; and, Other relevant limitations.

109 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 96 The specific recommendations from Steps 1 to 4 include: Infrastructure components that have been found to be vulnerable; Initial recommendations regarding possible remedial engineering actions, structure monitoring for a set period, or management actions; Infrastructure components that have adaptive capacity and require no further action at this time; Data gaps that require additional work or studies; Interactions that have been screened and prioritized, but not yet evaluated, and require further action; Any other conclusions, trends, insights, and limitations; and, Prioritized recommendations, where possible Limitations Major Assumptions Infrastructure The study included an assessment for both existing conditions and changes due to future climate change. Wherever possible and appropriate, the time frame used for future projections was the 30-year period of 2041 to 2070, or more commonly expressed as the 2050s. Assessment of vulnerability beyond this horizon was not conducted as it was agreed by the study team members that this would likely surpass the useful life of the infrastructure, without undertaking a significant reconstruction or rehabilitation. Climate The climate analysis and projections portion of this study included the establishment of a set of climate parameters describing climatic and meteorological phenomena relevant to the Toronto Pearson area and the selected infrastructure, as well as the determination of general probability scores reflective of the occurrence of each phenomenon, both historically and in the future. In addition, subsequent analysis involved the assignment of climate loads to the Engineering Analysis phase of the project. Data Sources The study did not identify any limitations due to data sources for the infrastructure or climate analysis. The reports and historical information regarding the facility design and operation were sufficient to complete the assessment. The data sources compiled for the climate analysis, both historical and future, were sufficient to complete the objectives of this portion of the study. A comprehensive list of references is included in Section 8.

110 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 97 Recommendations The following tables provide a summary of the recommendations for the components that have been assessed to be vulnerable. As mentioned previously, the vulnerabilities identified do not generally differentiate between the existing and future climate projections. The increase or decrease in vulnerability can only be attributed to the increased or decreases likelihood of the event occurring. Table 6-1 Recommendations for the Vulnerable Components of the Stormwater Quality Control Facilities Infrastructure Component Detention Basin Quality Ponds with bypass (vegetated & concrete ponds) Vulnerability Comments The capacity of water quality stormwater facilities may be exceeded when rainfall exceeds the design capacity (25mm). However, the facility will likely not lose functionality since it is equipped with a bypass. Recommendations Review stormwater quality control facilities operation during and/or after severe weather events to ascertain that bypass is operating as designed and detention basin is allowing proper settling. That monitoring should be on-going. Quality Ponds without bypass (vegetated & underground tanks) Functionality of the water quality component of stormwater facilities without a bypass will be impaired when rainfall exceeds the design capacity (25mm) of the detention basin, due to reduced particle settling time and potential resuspension. Review stormwater quality control facilities operation during and/or after severe weather events which may cause stormwater facilities to be non-functioning. Should inadequate settling action be occurring then remedial measures may be required. That monitoring should be ongoing. Quantity Ponds (vegetated & concrete ponds) Inlet/Outlet Structures All inlets, outlets, ditches, diversion chambers, weirs, etc. The projected increase in intensity of rainfall events may result in the capacity of quantity ponds being exceeded. The effects of an exceeded capacity for some quantity ponds (e.g. SWM 4) are unclear and may have unfavorable consequences. The maximum capacity of these components will very likely be exceeded during an extreme heavy rainfall. In the future, these events are projected to occur more frequently. Review stormwater quantity control facilities operation during and/or after severe weather events which may cause unwanted flooding and risk to airport operations. A separate flood risk study is currently underway and will conclude shortly with more detail hydrologic and hydraulic analysis. GTAA should meet with City of Mississauga to discuss downstream implications from extreme rainfall events. A separate flood risk study is currently underway and will conclude shortly with more detail hydrologic and hydraulic analysis. Table 6-2 Recommendations for the Vulnerable Components of the Stormwater Quantity Control Facilities Infrastructure Component Structural System The culvert Vulnerability Comments Projected increases in the intensity and frequency of extreme heavy rainfalls may result in the culvert s capacity being exceeded more frequently, and while Runway will likely not overtop during the future 100-year design storm, Derry Road upstream of the culvert may overtop. Recommendations GTAA should meet with TRCA & Region of Peel to discuss implications of Derry Road bridge under Extreme Heavy Rainfall events. A separate flood risk study is currently underway and will conclude shortly with more detail hydrologic and hydraulic analysis.

111 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 98 General Recommendations Given the potential consequences of flooding as a result of a future frequency shift in extreme rainfall events, it is recommended that GTAA closely monitor developments in relevant climate science and in the activities of TRCA, City of Mississauga and Ontario MNR, MOE and other provincial flood regulatory agencies in assessing and modifying stormwater management facility design criteria and performance standards in the context of the impacts of climate change on extreme and maximum rainfall and flood events. Furthermore, it should be noted that the recommendations are provided for vulnerable components that were identified as potential outcomes of climate change. Climate change was determined by climate analysis and projections, which in itself involved a certain level of uncertainty. It is therefore recommended that the climate analysis and projections be revisited if climate science is able to provide more certainty in the future. Generally, the results of the engineering analysis demonstrate that the stormwater facilities and the Spring Creek Culvert have relatively low vulnerability to potential future climate change. Part of the reason for the relatively low vulnerability is the excellent condition that the facilities are in; this is due to combination of resilient design, a high quality of construction, consistent inspections and maintenance.

112 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page Conclusions The subject of this vulnerability assessment was Selected Stormwater Facilities and Spring Creek Triple Cell Box Culvert to changing climate. These types of infrastructure are inherently robust structures designed to withstand severe inflow events. Given that generally the design parameters for these types of facilities are based on historical climate data, specifically design storms, it is certainly important to consider the potential effects of future climate change. During the study, the infrastructure was broken out into its various components, which included both the physical pieces of the actual infrastructure and the soft elements which are critical to its operation (personnel, procedures, communication devices, etc.). Having utilized the PIEVC Protocol to assess the facilities, the project team determined that, in general, the Stormwater Facilities have the capacity to withstand the existing and projected future climate (i.e. to the 2050s). However, it should be noted that the largest potential impact on many of the components, and the overall performance, could be changes to the inflow regimes due to changed precipitation events. Stormwater quality facilities without a bypass may be particularly vulnerable due to the potential impact excess inflow may have on their functionality. The soft elements of Spring Creek culvert were determined to have sufficient capacity to withstand the existing and projected future climate. The capacity of the culvert however may be vulnerable to projected increases in rainfall intensity and further analysis may be appropriate. The engineering analysis step of the protocol was difficult to complete in a quantitative manner as prescribed by the Protocol. This resulted in analysis based on the team s engineering judgment and experience operating the stormwater facilities and Spring Creek Triple Cell Box Culvert. While we feel this was an appropriate approach to complete the objectives of the study, it may be appropriate to complete more in-depth research and analysis to quantify vulnerabilities or capacities should there be specific climate component interactions which are of concern. The climate analysis did reveal some changes in frequency of climate events which will result in a decrease in vulnerability for the infrastructure. With the generally higher temperatures projected for the study area, there will be less probability, or less frequency of the low temperature dependant events such as freeze/thaw, snow accumulation and cold wave. This reduced frequency of occurrence will result in a decreased potential vulnerability from the events. This can be viewed as a potential positive impact of future climate change. The climate events posing the highest vulnerability to the stormwater facilities and Spring Creek culvert, particularly in terms of number of components potentially vulnerable, are generally extreme events such as extreme rainfall events (current and future), hurricanes and ice storms. While this was an expected outcome, it should be highlighted that the current climate science indicates that the possibility of these events occurring is going to increase in the future. Many of the vulnerabilities exist to extreme weather events such as tornados or hurricanes, which in the case of this study were assumed to occur in the facility s immediate vicinity. While it is difficult to completely protect the facilities from such events, there are actions which can be taken to minimize the operational risks and prepare for the events. These include: reviewing emergency response plans, and completing operational tests where power, communication and back-up systems are lost.

113 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page References 8.1. Infrastructure Airside Development Project, Stormwater Management Plan, Winter Associates and Gore & Storrie, April 1993 Airside Development Project, Stormwater Analysis Final Report No. 16, Winter Associates and Gore & Storrie, February 1991 Critical Issues in Aviation and the Environment, Transportation Research Board, March Design Brief on the Central De-Icing Facility, Marshall Macklin Monaghan, September 1997 Juliet Taxiway Extension Lester B. Pearson International Airport, Hydraulic Analysis of Spring Creek and Etobicoke Creek, May 2000 LBPIA Flood Risk Analysis, MacViro Consultants, LBPIA Silver Dart Drive Utility Corridor Study, Proctor & Redfern, Transtech, Acres International, Winter Associates, 1999 Lester B. Pearson International Airport, Airport North Development Preliminary Site Servicing Study, June 1999 Lester B. Pearson International Airport Boeing Lands Redevelopment Stormwater Management Study, Winter Burnside a division of R. J. Burnside & Associates Limited, April 2003 Master Stormwater Implementation Plan for Lester B. Pearson International Airport, Winter Associates, February, 1991 Phase 2 Stormwater Management Master Plan, CH 2 M HILL Engineering Ltd., November 1996 Phase 1 Stormwater Management Master Plan, CH 2 M HILL Engineering Ltd., October 1995 Preliminary Design Report for Stormwater Facility WM4, Winter Burnside a division of R. J. Burnside & Associates Limited, April 2002 Spring Creek Culvert Rehabilitation at Toronto Pearson International Airport, Morrison Hershfield, January 2012 Storm Drainage Study for LBPIA Area 13A, Winter Burnside a division of R. J. Burnside & Associates Limited, September 2003 Stormwater Analysis Update for LBPIA, Airside Development Project, Drainage Area No Area Affected by Dual Taxiway Project, Winter Associates, September 1997

114 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 101 Stormwater Study for GTAA-LBPIA Property located North of Derry Road East Between Torbram Rd. and Cattrick Street, March 2001 Terminal Development Project Stormwater Management Report, Groundside Lands (Drainage Area No. 5), GTAGA, 1998 The Airport Master Plan , Greater Toronto Airport Authority, December 2007 Updated Reportfor Master Stormwater Implementation Plan for Lester B. Pearson International Airport, Winter Environmental Consulting, January 2003 Utilities Master Plan, Stormwater Management Facilities, Draft, Simcoe Engineering Group, October Climate Data Ang-Olson, Jeffrey. What Does Climate Change Mean for Airport Planning? ICF International: Toronto, Print. Airports Council International. Planning Airport Adaptation to Climate Change. Montreal, Auld, H., Klaassen, J., Morris, R., Fernandez, S., Eng, S., Cheng, S., Maclver, D., Bernstein, D. Building Climate Change into Codes and Standards. Environment Canada. Birmingham Airport, UK. Climate Change Adaptation Report. Birmingham, Print Cheng, C.S., Li, G., Li, Q., Auld, H. and MacIver, D. Climate Change and Extreme Rainfall-related Flooding and Surface Runoff Risks in Ontario. Plain Language Summary Report. Environment Canada: City of Mississauga, ON. Living Green Master Plan Presentation Staff & Stakeholder Workshops. Mississauga, City of Windsor, ON. Climate Change Adaptation Plan. Windsor: Print Coulibaly, P. and Shi, X. Ministry of Transportation Ontario, ON. Identification of the Effect of Climate Change on Future Design Standards of Drainage Infrastructure in Ontario. McMaster University, Coulibaly, P. Effects of Climate Change on Design Standards of Drainage Infrastructure. McMaster University. CSA Standards. Mainstreaming the Risk-Based Management of Climate Change Impacts in Canada: Which Guidance is Needed? De Jong, C. Toronto s Climate Change Adaptation Strategy Ahead of the Storm. Urban Risk Management. Toronto, Government of Canada. Climate Change Impacts and Adaptation: A Canadian Perspective. Ottawa. Government of Ontario. Climate Action- Adapting to Climate Change, Protecting Our Future

115 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 102 Gregg R.M., Feifel, K.M., Kershner, J.M., and Hint, J.L. The State of Climate Change Adaptation in the Great Lakes Region. EcoAdapt: Washington, Print. Impacts, Opportunities, and a Made in Peel Solution to Combat Climate Change, Region of Peel, March 2011 Lapp, D. Infrastructure Climate Risk Assessment: Principles and Applications. Toronto, Ouranos, Quebec. Climate Change Scenario over Ontario Based on the Canadian Regional Climate Model (CRCM4.2). Quebec. Planning Airport Adaptation to Climate Change, ACI World Environment Standing Committee, April 2011 Region of Peel, ON. Peel Climate Change Strategy. A Strategic Plan for Climate Change for the Geographic Region of Peel. Impacts, Opportunities, and a Made in Peel Solution to Combat Climate Change. Ontario, Richardson, G. Climate Change Risk Assessment Tools for Canadian Communities. Natural Resources Canada. Ottawa, Solaiman, T.A. and Simonovic, S.P. Water Resources Research Report Development of Probability Based Intensity-Duration-Frequency Curves Under Climate Change. University of Western ON, What does Climate Change Mean for Airport Planning?, ICF International, January 2009 Vincent, L.A., and Gullett, D.W. Canadian Historical and Homogenous Temperature Datasets for Climate Change Analyses. International Journal of Climatology 19 (1999): Print PIEVC Case Study AECOM, ON. Toronto Hydro-Electric System Public Infrastructure Engineering Vulnerability Assessment Pilot Case Study. Electrical Distribution Infrastructure Final Report. Case Study. Toronto, AMEC, UK. National Engineering Vulnerability Assessment of Public Infrastructure to Climate Change. City of Welland Stormwater and Wastewater Infrastructure Assessment Technical Report. United Kingdom, Associated Engineering, ON. City of Calgary Water Supply Infrastructure. Climate Change Vulnerability Risk Assessment. Toronto, BC Water & Waste Association (BCWWA), BC. Stormwater and Watershed Vulnerability: Connecting Rural and Urban Risks Using PIEVC. City of Castlegar, ON. Stormwater Infrastructure Climate Change Vulnerability Assessment. Castlegar: Print. City of Greater Sudbury, ON. Adapting to Climate Change Canada s First National Engineering Vulnerability Assessment of Public Infrastructure. Sudbury: Print. Engineers Canada. Infrastructure Climate Risk Assessment Backgrounder. Ottawa, 2012.

116 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 103 GENIVAR, ON. Climate Change Vulnerability Assessment for Culverts. Markham: Print. GENIVAR, ON. National Engineering Vulnerability Assessment of Public Infrastructure to Climate Change. Climate Change Vulnerability Assessment of the Town of Prescott s Sanitary Sewage System. Markham, Nodelcorop Consulting Inc., AB. Climate Change Engineering Vulnerability Assessment. Coquihalla Highway (B.C. Highway 5) Between Nicolum River and Dry Gulch. Alberta, Print. Nodelcorop Consulting Inc., AB. Climate Change Engineering Vulnerability Assessment. B.C. Yellowhead Highway 16 Between Vanderhoof and Priestly Hill. Alberta, Print. Nodelcorop Consulting Inc., AB. Executive Summary Climate Change Engineering Vulnerability Assessment. B.C. Yellowhead Highway 16 Between Vanderhoof and Priestly Hill. Alberta, Print. PIEVC Adapting to Climate Change Canada s First National Engineering Vulnerability Assessment of Public Infrastructure. Ottawa, PIEVC-Canada-Wide Assessment Sampling Study. Adapting to Climate Change Canada s First National Engineering Vulnerability Assessment of Public Infrastructure PIEVC Case Studies Summaries: Adapting to Climate Change Canada s First National Engineering Vulnerability Assessment of Climate Infrastructure. Case Study. Ottawa, PIEVC Case Studies: Codes, Standards and Related Instruments (CSRI) Review for Water Infrastructure and Climate Change. Case Study. PIEVC, PIEVC-Government of Canada Buildings, Ottawa, ON. Adapting to Climate Change Canada s First National Engineering Vulnerability Assessment of Public Infrastructure PIEVC-City of Edmonton, Alberta. Adapting to Climate Change Canada s First National Engineering Vulnerability Assessment of Public Infrastructure PIEVC-Thermosyphon Foundations, Northwest Territories and Yukon. Adapting to Climate Change Canada s First National Engineering Vulnerability Assessment of Public Infrastructure., PIEVC-Literature Reviews. Adapting to Climate Change Canada s First National Engineering Vulnerability Assessment of Public Infrastructure PIEVC-Metro Vancouver, British Columbia. Adapting to Climate Change Canada s First National Engineering Vulnerability Assessment of Public Infrastructure PIEVC-Ouranos Climate Change Summary Report. Adapting to Climate Change Canada s First National Engineering Vulnerability Assessment of Public Infrastructure PIEVC-PIEVC Committees Rosters. Adapting to Climate Change Canada s First National Engineering Vulnerability Assessment of Public Infrastructure

117 Toronto Pearson Infrastructure Climate Vulnerability Assessment Page 104 PIEVC-Portage La Prairie, Manitoba. Adapting to Climate Change Canada s First National Engineering Vulnerability Assessment of Public Infrastructure PIEVC- Resilient Cities nd World Congress on Cities and Adaptation to Climate Change. Beyond the Storm: Risk-Based Processes and Tools to Enable Better Understanding and Management of Climate Change Risks. Toronto, PIEVC-Town of Placentia, Newfoundland. Adapting to Climate Change Canada s First National Engineering Vulnerability Assessment of Public Infrastructure Urban Systems, AB. Stormwater Infrastructure Climate Change Vulnerability Assessment for the City of Castlegar, BC, University of Saskatchewan, SK. Assessment of the Engineering Building s Vulnerability to Climate Change. Saskatchewan, 2012.

118 Toronto Pearson Infrastructure Vulnerability Assessment Appendix A Climate Analysis and Projections

119 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Table of Contents Climate Analysis and Projections Introduction List of Climate Variables Definitions Climate Data Sources Historical Future Climate Variability Probability of Occurrence Overview Climate Parameters High Temperature Low Temperature Heat Wave Cold Wave Extreme Diurnal Temperature Variability Freeze Thaw Extreme Heavy Rain Heavy Rain Heavy 5 Day Total Rainfall Winter Rain Freezing Rain Ice Storm Heavy Snow Snow Accumulations Blowing Snow/Blizzard Lightning Hailstorm High Wind Tornado Drought/Dry Period Heavy Fog Summary of Findings Page i

120 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections LIST OF TABLES Table A 1 Protocol Probability Scale Factors and Mechanism Used to Consistently Assign Probability Scores...4 Table A 2 High Temperature Results for the Period *...6 Table B 3 Low Temperature Results for the Period *...8 Table A 4 Snowfall Results for the Period Table A 5 High Wind Results for the Period Table A 6 Tornado Results for the Period Table A 7 Probability Scoring Summary...33 Page ii

121 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Climate Analysis and Projections 1.0 Introduction The TRCA Vulnerability Assessment to Climate Change for Flood Control Dams, 2009 was selected as the principle source of current climate data and future climate projections for the Toronto Pearson study. Many of the climate parameters contained in the TRCA study are relevant to Toronto Pearson. The TRCA study was guided by the PIEVC Protocol and developed a preliminary list of climate parameters based on climate events and change factors included in Appendix A of the PIEVC Protocol. Justification for parameter selection was also based on the parameter s potential to present vulnerability to the infrastructure and its components as a result of either an extreme or persistent occurrence. That study also conducted an analysis which resulted in the determination of general probability scores reflective of the occurrence of each phenomenon, both historically and in the future. The following presents the relevant climate information from the TRCA Vulnerability Assessment that was considered and utilized in the Toronto Pearson study. 2.0 List of Climate Variables The following climate parameters were selected: High Temperature Heavy 5 Day Total Rainfall Lightning Low Temperature Winter Rain Hailstorm Heat Wave Freezing Rain Hurricane/Tropical Storm Cold Wave Ice Storm High Wind Extreme Diurnal Temperature Variability Heavy Snow Tornado Freeze Thaw Snow Accumulation Drought/Dry Period Heavy Rain Blowing Snow/Blizzard Heavy Fog Frost Wet Days Dust Storms 3.0 Definitions Definitions for the aforementioned climate parameters were established and were based on three factors: a) the usefulness of the climate parameter in determining vulnerability; b) the availability of information; and c) the ability to relate this information to a probability. In most cases, the usefulness of the parameter in determining vulnerability meant referencing the phenomenal or extreme aspects of a climate event (i.e. in the absence of extremes, vulnerability may Page 1

122 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections not exist). In some instances, the mere occurrence of an event (singular or otherwise) was useful in determining vulnerability (e.g. tornado, hurricane), whereas for others, only an extreme occurrence of the event was deemed useful in determining vulnerability (e.g. high temperature of greater than 35 C). The latter required that a threshold be established, which was reflective of an extreme event for each applicable parameter. Two tiers of parameter definitions were established: Tier one: Commonly occurring events, which are almost certain to occur in a given year and whose effects and impacts to infrastructure are most likely related to persistence rather than a single occurrence. These parameters were defined as the probability of exceeding the historical average occurrence (i.e. Canadian Climate Normals) in a given year; and, Tier two: The occurrence of extreme or phenomenal events in a given year. 4.0 Climate Data Sources 4.1. Historical Historical The historical climate analysis was conducted using data from a variety of sources. Information was retrieved from Environment Canada s Canadian Climate Normals. Climate Data Online (Environment Canada, 2008), the Ontario Node of the Canadian Atmospheric Hazards Network (Environment Canada, 2009) and the Canadian Daily Climate Data (CDCD V1.02) program (Environment Canada, 2007). For these data sources, Toronto Pearson International Airport weather station data was used as a result of the station s location and completeness of data over the station s period of record. For certain climate parameters (i.e. ice storm, lightning, hurricane, and tornado) information was either not available from the above mentioned sources or was not representative of the same geographical area and not specific to Toronto Pearson International Airport. In these instances there was a need to select alternative sources of information and/or use information representative of a different geographical area. These cases are clearly documented within the specific sections of this chapter. To assess historical trends in climate, various scientific journal articles were reviewed. It is noted that parameter indices and scales (temporal and spatial) from the literature often varied from the study s established climate parameter definitions. However, due to resource limitations, the team agreed to accept varying levels of applicability as long as it could be used to make logical assumptions and connections with study definitions Future Future climate projections were analyzed using climate model outputs from Environment Canada s Canadian Climate Change Scenario Network (CCCSN) Scatter Plots (CCCSN, 2007b) and Bioclimate Profiles (CCCSN, 2007a), the Intergovernmental Panel on Climate Change (IPCC) 4th Assessment Report (AR4, 2007) Regional Climate Projections chapter (and others, where applicable), and scientific journal articles presenting regional and local projections and predictions. Page 2 of 34

123 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Using the CCCSN, output from IPCC recognized AR4 global climate models was extracted for the model grid cell encompassing the Toronto area for each of the three emissions scenarios used, A2 (high) A1B (medium) and B1 (low). Outlying global models that were not effective in reproducing aspects of the southern Ontario climate were identified and removed (as previously conducted by the Toronto and Region Conservation Authority) and the median output from the remaining models was considered. In addition to considering the median output of all models, the range of output across the various models was also considered in assessing the confidence with which the output could be used. It should be noted that for some climate parameters, output was not available from all of the global climate models for which access is available on the CCCSN website. Similar to limitations associated with the available literature for historical trends, challenges were experienced in identifying climate projections for certain parameters, as information was often only available at global or regional scales (i.e. not specific to the Toronto Area), and/or by referencing different benchmarked time periods (i.e. not ) or future planning horizons (i.e. not 2050s). As a result, difficulties in making direct comparisons between historical and future results were occasionally encountered. In such cases, the professional judgment of the project team was often applied in the ranking of existing and future probability, which was considered reasonable given the level of accuracy and precision required by the protocol. The way that this was managed was by ensuring enough support was available to justify decisions; for example, a change in probability score between existing and future scenarios for a given parameter. In this sense, the term enough meant having said support (e.g. baseline information in the form of model projection output being supported by scientific literature relating to the same or similar spatial and temporal setting) such that, in the event that the review and scoring process was to be repeated by others, one would likely come to the same conclusion (at least in terms of direction, and possible in magnitude of change). Alternatively, where supporting projection data were clearly inconsistent or in conflict with one another, scores remained unchanged. 5.0 Climate Variability Probability of Occurrence 5.1. Overview The process of scoring the probability of an event s occurrence was conducted by first identifying historical occurrences and then by calculating a frequency (i.e. the number of occurrences within a time frame divided by the number of years in that time frame). In some instances, the data was already presented (by the relevant source) as a frequency. A score between 0 7 was assigned to each parameter by subjectively relating the known or calculated probability to one of the descriptive terms presented in Method A of the Protocol s Probability Scale Factors (shown in Table A 1). In order to initially relate numeric probabilities to descriptive terms, the team followed a consistent thought process to establish relational benchmarks. The following example explains how this was conducted: The process started by framing the question what is the likelihood that an event will occur in a given year? If one considers a climate parameter calculated to have a historical annual frequency of 0.5 then this can be considered to mean that the climate event would occur approximately once every other year. The team evaluated the various Method A descriptive terms and collectively agreed that, if the event would occur approximately once every other year, then the term moderate/possible best represented the likelihood of its occurrence in a given year. That is to say, by no means is it certain that Page 3 of 34

124 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections it will occur every year. The PIEVC Protocol s Figure 21 relates the term moderate/possible to a Probability Score of 4. This was established as a middle relational benchmark. Following the same rationale as above, parameters with known or calculated probabilities of greater than 2 were considered very likely to have an event occur in a given year based simply on the historical record. Therefore, any probabilities greater than two were agreed to relate best to the term certain/highly probable. The PIEVC Protocol s Figure 21 relates the term certain/highly probable to a Probability Score of 7. This was established as the upper relational benchmark. The Protocol s Figure 21 relates the term negligible or not applicable to a Probability Score of 0. It was agreed that regardless of how low the frequency, the term negligible or not applicable did not apply to any parameter being evaluated in this particular study and as such, no scores of 0 would be assigned. The above three rationales, provided relational benchmarks for the team to consider during this assessment. Once completing several additional examples, the team continued to develop a consistent process (or self calibration) in ascribing values. In order to ensure this consistency was maintained for all parameters, a mechanism was developed which related frequency ranges to PIEVC scores. This mechanism is shown in Table A 1 below (right column). Following this mechanism, historical probabilities were matched to the appropriate numerical ranges. Table A 1 Protocol Probability Scale Factors and Mechanism Used to Consistently Assign Probability Scores PIEVC Probability Score Method A Calculated Number of Occurrences per Year (range)* 0 negligible or not applicable 0 1 improbable / highly unlikely >0 to remote 0.05 to occasional 0.1 to moderate / possible 0.25 to often 0.75 to probable 1.25 to 2 7 certain / highly probable >2 *Ranges were developed subjectively based on completing several examples of relating probabilities to descriptive terms. It is noted that tier one parameters were treated slightly different. As per their definition these parameters represent commonly occurring events whose effects and impacts to infrastructure are most likely related to persistence rather than a single occurrence (i.e. freeze thaw). If they were not treated independently, their frequency of occurrence in a given year (always greater than two) would Page 4 of 34

125 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections repeatedly be assigned a Probability Score of 7 or certain/highly probable. The team decided that this was undesirable because it would prevent the potential for any upward change in future scenario scores and would unjustifiably influence the overall risk scores. In order to ensure that these types of parameters were set on a level playing field with the more extreme parameters, the following methodology was established. Following the calculation of the frequency of occurrences within a given year (same as for tier two parameters), this value, which was often high (e.g. 85 for freeze thaw cycles), was used as a benchmark within the definition itself (different from tier two parameters). This was done because the initial calculated frequency presented little use in assessing vulnerability of the infrastructure (i.e. the likelihood of 1 freeze thaw event occurring was meaningless). Continuing with the freeze thaw example, an original study definition would have been the number of days in a given year with maximum temperature greater than 0 C and minimum temperature less than 0 C, whereas the revised definition becomes 85 or more days with maximum temperature greater than 0 C and minimum temperature less than 0 C. This allows for an appreciation of the event s historical average occurrence (annual) experienced over the life of the airport as well as establishing a point of reference to consider when evaluating future probability scores (i.e. the likelihood of more or less than the historical average occurring). For the purposes of this study, it was agreed that for tier one parameters, half of the time (0.5), a given year would experience more than an event s historical average (i.e. 85 freeze thaw events) and the other half (0.5), a given year would experience less than an event s historical average. It is recognized that in order to be statistically meaningful, this middle reference point should indeed be the data set s median, rather than the mean, however a pragmatic approach was taken based on readily available information and the level of accuracy required. Based on the relational benchmarks established above and the resulting mechanism developed, tier one definitions in the historical context (frequency of 0.5) were deemed to have a moderate/probable chance of occurrence. As such, a Probability Score of 4 was assigned. When considering the future scenario (2050s), probability scores were assigned by changing (increasing or decreasing) or maintaining the previously established historical scores and not by calculating new probabilities. Scores were assigned after understanding future climate projections via the analysis of CCCSN global climate model output, bioclimate profiles, and/or review of available scientific journal articles. Once projections were obtained, the probability scores were re evaluated for each parameter and sometimes adjusted. Where projection information was not available, probability scores remained unchanged between historical and future scenarios. In addition to understanding future projections, historical trends were discussed. It is noted that trends were not used to alter future probability scores, but rather provided background information to projections or predictions. Page 5 of 34

126 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections 5.2. Climate Parameters High Temperature Definition For the purposes of this study, the measure of high temperature was defined as the number of days where the maximum temperature is greater than 35 C in a given year. As the highest temperature ever recorded at Toronto Pearson International Airport was 38.3 C (August 25, 1948) (Environment Canada, n.d.), a threshold of 35 C was considered representative of extreme or phenomenal high temperature. This parameter is a tier two definition Historical Climate Findings Climate Normals describe and summarize average climate conditions for a particular location, typically over a 30 year period. In this study Climate Normals were obtained for Toronto Pearson International Airport based on data from the years 1971 to The information yielded from these Normals relating to high temperature is shown in Table A 2 below. On average there were 0.54 days per year with a maximum temperature greater than 35 C. Table A 2 High Temperature Results for the Period * Description Days/Year Number of days with a maximum temperature > 30 C 12.6 Number of days with a maximum temperature > 35 C 0.54 *(Environment Canada, n.d.) Probability Scoring Based on the findings above, 0.54 (days per year with a maximum temperature greater than 35 C) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 4, with a moderate/possible chance of occurrence Trends Trends in historical temperatures for southern Canada from the years 1900 to 1998 were examined by Bonsal, Zhang, Vincent, and Hogg (2001). Although their research presents significantly increasing trends to the lower and higher percentiles of daily minimum and maximum temperature distribution (1st, 5th & 10th percentile for extreme low and 90th, 95th & 99th percentile for extreme high), no consistent trends for the higher percentiles of summer daily maximum temperature were identified, thus indicating little change to the number of extreme hot summer days. Vincent and Mekis (2006) showed that the number of annual warm events (days above the 90th percentile) over Canada increased significantly throughout the years 1950 to In addition, Zhang, Vincent, Hogg, and Niitsoo (2000) found that over the same time period, annual mean temperatures Page 6 of 34

127 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections have increased by 0.9 C in southern Canada (south of 60oN), however relatively smaller increases have occurred in daily maximum temperature (especially when compared to increases in daily minimum temperature). Furthermore, their research, which also dealt with indices of abnormal climate (i.e. below the 34th percentiles and above the 66th percentiles), indicated that southern Canada has not become hotter, but rather less cold. The above studies indicate that little to no increases have occurred with respect to extreme hot temperatures. It is noted that these studies are not specific to the Toronto area and do not define high temperature the same as this report (i.e. the number of days with maximum temperature greater than 35 C). In addition, some of the trends assessed annual data, which prevented the findings from being directly comparable to daily maximums Climate Projections Findings Current climate projections indicate that temperatures for most of North America will increase and likely exceed the global mean warming (Christensen et al., 2007, IPCC). This projected increase in temperature is expected to be between 2 C to 3 C and is based on annual means (Christensen et al., 2007, IPCC). In addition, it is very likely that high temperature extremes will increase globally (Meehl et al., 2007, IPCC). These increases represent global mean warming and do not relate directly to temperatures greater than 35 C. A study by Kharin, Zwiers, Zhang and Hegerl (2007) indicated that changes in warm extremes generally follows changes in the mean summertime temperature. Projections specific to Toronto are presented in a study by Cheng et al. (2005), where the average of five climate change scenarios is used. The study projects that the number of days exceeding 30 C will more than double by the 2050s. Although not directly indicated, this finding would suggest the potential for the number of days with temperatures greater than 35 C to increase as well. IPCC recognized climate model outputs available on the CCCSN, project an annual mean maximum air temperature increase of approximately 2.5 C for the grid cell encompassing the Toronto area. It is noted that this annual value will not necessarily influence changes in the number of days with temperatures exceeding 35 C. Probability Scoring The probability score for the future was adjusted from the historical value of 4 to a revised probability score of 5 based on the above noted climate projections and the following rationale. Climate Normals (based on the historical record ) revealed 12.6 days per year with temperatures exceeding 30 C and 0.54 days exceeding 35 C. This is a large difference in the number of days even though the thresholds are relatively close. Considering mean maximum air temperatures are projected to increase by 2.5 C (climate model output for Toronto grid cell) one might assume that this increase would be enough to elevate a certain percentage of the existing greater than 30 C days (12.6) to a temperature above the 35 C threshold. Furthermore, if the number of days exceeding 30 C is projected to more than double by the 2050s (Cheng et al. s 2005 study), then it might also be expected that a certain proportion of the greater than 30 C days will also exceed 35 C. As a result, it was decided that an increase in the number of days above 35 C would be large enough to justify an increase of 1 in the probability score. Page 7 of 34

128 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Low Temperature Definition For the purposes of this study, the measure of low temperature was defined as the number of days where the minimum temperature is less than 30 C in a given year. As the lowest temperature ever recorded at Toronto Pearson International Airport was 31.3 C (January 4, 1981) (Environment Canada, n.d.), a threshold of 30 C was considered representative of extreme or phenomenal low temperature. This parameter is a tier two definition Historical Climate Findings The information yielded from the Canadian Climate Normals for Toronto Pearson International Airport relating to low temperature is shown in Table B 3 below. On average there were 0.1 days per year with a minimum temperature below 30 C. Table B 3 Low Temperature Results for the Period * Description Days/Year Number of days with a minimum temperature < 20 C 5.2 Number of days with a minimum temperature < 30 C 0.1 *(Environment Canada, n.d.) Probability Scoring Based on the findings above, 0.1 (days per year with a minimum temperature below 30 C) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 3, with an occasional chance of occurrence Trends Trends in historical temperatures for southern Canada were examined in a study by Bonsal et al. (2001), which showed a significant decrease in the number of days with extreme low temperatures (e.g. minimum temperature less than 5th percentile) from 1900 to 1998 during winter. Vincent and Mekis (2006) showed that the number of annual cold events (days below the 10th percentile) over Canada decreased significantly throughout the years 1950 to Zhang et al. (2000) found that annual mean temperatures have increased by 0.9 C over the last century in southern Canada (south of 60oN) and that large increases in daily minimum temperatures have occurred. Furthermore, their research, which also dealt with indices of abnormal climate (i.e. below the 34th percentiles and above the 66th percentiles), indicates that southern Canada has not become hotter, but rather less cold. The above studies indicate that substantial decreases in winter days with extreme low temperatures and increases in daily minimum temperatures have occurred. It is noted that these studies are not specific Page 8 of 34

129 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections to the Toronto area and do not define low temperature the same as this report (i.e. the number of days with minimum temperature less than 30 C). In addition, some of the trends assessed annual data, which prevented the findings from being directly comparable to daily minimums Climate Projections Findings Current climate projections indicate that temperatures for most of North America will increase and likely exceed the global mean warming (Christensen et al., 2007, IPCC). This projected increase in temperature is expected to be between 2 C to 3 C and is based on annual means (Christensen et al., 2007, IPCC). In addition, the fourth IPCC assessment report concluded that there will be a reduced risk of extreme low temperatures (Meehl et al., 2007, IPCC). Cheng et al. (2009b) used a statistical downscaled approach on five general circulation models (GCM) outputs to derive future climate information and found that it is very likely that cold related mortality will decrease by about 60% in Toronto by the 2050s, implying a warming of extreme low temperature. A study by Kharin et al. (2007) indicates that cold extremes warm faster than warm extremes by about 30% 40%, globally averaged. IPCC recognized climate model outputs available on the CCCSN, project an annual mean minimum air temperature increase of approximately 2.7 C for the grid cell encompassing the Toronto area. It is noted that this annual value will not necessarily influence changes in the number of days with temperatures below 30 C. Probability Scoring The probability score for the future was adjusted from the historical value of 3 to a revised probability score of 2 based on the above noted climate projections and trends, which both indicate a decrease in the number of extreme cold days and warming temperatures Heat Wave Definition A meteorological heat wave is defined by Environment Canada (Meteorological Service of Canada (MSC) Ontario Region, 2009b) as three or more consecutive days in which the maximum temperature is greater than or equal to 32 C. For the purposes of this study, the number of heat wave occurrences within a given year was considered. This parameter is a tier two definition Historical Climate Findings Daily temperature data for Toronto Pearson International Airport, obtained from Environment Canada s Climate Data Online (Environment Canada, 2008), was analyzed for the occurrences of heat waves from 1971 to 2000 based on the above definition. It was determined that 17 heat waves occurred during this 30 year period. This translates to an average of 0.57 heat waves per year (17/30). The majority of heat waves lasted for the defining three days; however, there was one heat wave that lasted for 6 days, three heat waves that lasted for 5 days, and two heat waves that lasted for 4 days. Page 9 of 34

130 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Probability Scoring Based on the findings above, 0.57 (heat waves per year) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 4, with a moderate/possible chance of occurrence Trends No studies specifically analysing trends of heat waves were identified, although various warming trends were established in the articles reviewed Climate Projections Findings The Global Climate Projections chapter of the IPCC 4th Assessment Report indicates that there will likely be an increasing risk of more frequent and longer heat waves (Meehl et al., 2007, IPCC). In addition, there is expected to be an increase in the dryness of summer with drier soil conditions, which could contribute to more severe heat waves (Meehl et al., 2007, IPCC). As these projections are made in a global context, they cannot be directly related to the Toronto area. A study by Cheng et al. (2005), which used the average of five climate change scenarios, found that the number of days exceeding 30 C is projected to more than double by the 2050s for Toronto. This finding, along with the projected annual mean maximum air temperature increase of approximately 2.5 C (climate model output for Toronto grid cell suggest that the number of days with temperatures greater than or equal to 32 C (temperature component threshold for heat waves) is likely to increase, thereby increasing the number of days where heat wave conditions are possible. It is noted that the mean maximum air temperature increase of 2.5 C is an annual value and will not necessarily reflect changes in the summer season. Climate model outputs available on the CCCSN (for Toronto grid cell) also project that the maximum heat wave duration will increase by approximately 22 days by the 2050s. However, this is not directly comparable data as the CCCSN uses the definition of a heat wave as a maximum period greater than 5 consecutive days with the maximum temperature greater than 5 C above the baseline maximum temperature normal. Probability Scoring The probability score for the future was adjusted from the historical value of 4 to a revised probability score of 5 based on the above noted climate projections. Similar logic was used in the evaluation of heat waves as was used for high temperature Cold Wave Definition A cold wave is defined by Environment Canada (MSC Ontario Region, 2005a) as a day in which the minimum temperature is below 20 C and the maximum temperature is not above 10 C. For the purposes of this study, the definition of a cold wave was altered slightly to be three or more consecutive days having a minimum temperature below 20 C and a maximum temperature below 10 C. The number of cold wave occurrences within a given year was considered. This altered definition related Page 10 of 34

131 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections better to the Heat Wave definition (above) and differentiated this parameter from low temperature (discussed above). This parameter is a tier two definition Historical Climate Findings Daily temperature data for Toronto Pearson International Airport, obtained from Environment Canada s Climate Data Online (Environment Canada, 2008), was analyzed for the occurrences of cold waves from 1971 to 2000 based on the above definition. It was determined that 5 cold waves occurred during this 30 year period. This translates to an average of 0.17 cold waves per year (5/30). All cold waves lasted for the defining three days with the exception of one, which lasted for 6 days. Probability Scoring Based on the findings above, 0.17 (cold waves per year) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 3, with an occasional chance of occurrence Trends No studies specifically analyzing trends of cold waves were identified, although various warming trends were established in the articles reviewed Climate Projections Findings Current climate projections indicate that temperatures for most of North America will increase and likely exceed the global mean warming (Christensen et al., 2007, IPCC). This projected increase in temperature is expected to be between 2 C to 3 C and is based on annual means (Christensen et al., 2007, IPCC). The fourth IPCC assessment report concluded that there will be a reduced risk of extreme low temperatures. Furthermore, global climate projections indicate that there will likely be a decline in the frequency of cold air outbreaks (two or more consecutive days with temperatures below the present mean by two standard deviations) in winter by % (using A1B scenario) in the northern hemisphere (Meehl et al., 2007, IPCC). In addition, Cheng et al. (2009b) used a statistical downscaled approach from five general circulation models (GCM) to derive future climate information and found that it is very likely that cold related mortality will decrease by 60% in Toronto, demonstrating a warming of extreme low temperature. IPCC recognized climate model outputs available on the CCCSN, project an annual mean minimum air temperature increase of approximately 2.7 C for the grid cell encompassing the Toronto area. Although this annual value does not necessarily reflect changes in the winter season. Probability Scoring The probability score for the future was adjusted from the historical value of 3 to a revised probability score of 2 based on the above noted climate projections and trends (for low temperature), which both indicate a decrease in the number of extreme cold days and warming temperatures. Similar logic was used in the evaluation of cold waves as was used for low temperature. Page 11 of 34

132 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Extreme Diurnal Temperature Variability Definition Diurnal temperature variability is the difference between the maximum and minimum temperature in a day (i.e. the daily swing in temperature). For the purposes of this study, this parameter was defined as the number of days experiencing a diurnal temperature variability of greater than 25 C in a given year. As the maximum diurnal temperature variability ever recorded at Toronto Pearson International Airport was 32.8 C (March 4, 1950) (Environment Canada, 2008), a threshold range of 25 C was considered representative of extreme or phenomenal diurnal temperature variation. This parameter is a tier two definition Historical Climate Findings Daily temperature data for Toronto Pearson International Airport, obtained from Environment Canada s Climate Data Online (Environment Canada, 2008), was analyzed for the occurrences of extreme diurnal temperature variability from 1971 to 2000 based on the above definition. It was determined that there were 5 occurrences of extreme diurnal temperature variability during this 30 year period. This translates to an average of 0.17 occurrences per year (5/30). Probability Scoring Based on the findings above, 0.17 (extreme diurnal temperature variability occurrences per year) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 3, with an occasional chance of occurrence Trends Vincent and Mekis (2006) discovered that changes (warming) in night time temperatures were more pronounced than changes in daytime temperatures (throughout Canada) leading to a decrease in the diurnal temperature variation for the years 1900 to Trends examined for the period 1950 to 2003 show a decrease of approximately 0.5 C to 1.0 C in diurnal temperature variability at certain stations including southern Ontario (Vincent and Mekis, 2006). Zhang et al. (2000) discovered that annual mean temperatures have increased by 0.9 C over the last century in southern Canada. The maximum daily temperature was found to have relatively smaller increases compared to the minimum daily temperature for the years 1900 to This led to a decrease in diurnal temperature variability of C. It is noted that these studies are not specific to the Toronto area and do not define extreme diurnal temperature variability the same as this report (i.e. the number of days experiencing a diurnal temperature variability of greater than 25 C) Climate Projections Findings The IPCC global climate projections indicate a decrease in the diurnal temperature variation in most regions (Meehl et al., 2007, IPCC). In addition, IPCC recognized climate model outputs available on the CCCSN for the grid cell encompassing the Toronto area, project an annual mean maximum air temperature increase of approximately 2.5 C and an annual mean minimum air temperature increase of Page 12 of 34

133 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections approximately 2.7 C. This indicates that minimum air temperatures are likely to increase more than maximum air temperatures thus reducing variability. Furthermore, climate model outputs from the CCCSN indicate a decrease of 1.42 C in the extreme temperature range (difference between the maximum air temperature and minimum air temperature within a given year) for the 2050s. It is noted that these data represent annual values and cannot be directly related to a diurnal temperature range. Probability Scoring The probability score for the future was adjusted from the historical value of 3 to a revised probability score of 2 based on the above noted climate projections and trends, which both indicate a decrease in the diurnal (and annual) temperature variability Freeze Thaw Definition For the purposes of this study, freeze thaw was defined as the average number of days (85 as described below) in a given year, which had a maximum temperature greater than 0 C and a minimum temperature less than 0 C (CCCSN, n.d.). This parameter is a tier one definition Historical Climate Findings Daily temperature data for Toronto Pearson International Airport, obtained from Environment Canada s Canadian Daily Climate Data program (CDCD) (Environment Canada, 2007), was analyzed for the occurrence of freeze thaw cycles from 1971 to 2000 based on the above definition. It was determined that 2,559 days with freeze thaw occurred during this 30 year period. This translates to an average of 85.3 days per year (2,559/30). Probability Scoring As freeze thaw was established as a tier one definition, the standardized probability scoring process (for tier one parameters) was employed. Based on the assumption that 0.5 represents the probability that the historical average number of freeze thaw events (85) would occur in a given year, established ranges in Table A 1 indicate that a probability score of 4 be ascribed, with a moderate/probable chance of occurrence Trends Ho and Gough (2006) determined that for the years 1960 to 1989 there was an unspecified decrease in the annual number of freeze thaw cycles for a study site located in downtown Toronto, even though the Toronto Pearson International Airport station did not exhibit a significant trend. It is noted that this study s definition of freeze thaw (i.e. having a maximum temperature greater than or equal to 0 C and a minimum temperature less than or equal to 1 C) differed from this report s definition (i.e. 85 days with a maximum temperature greater than 0 C and a minimum temperature less than 0 C). Page 13 of 34

134 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Climate Projections Findings Ho and Gough (2006), using predictive capacities of the 2nd and 6th polynomial equations (monthly temperature versus monthly number of freeze thaw cycles) on established trends (in Toronto) concluded that changes in freeze thaw cycle frequencies will not be significant under synthetic warming conditions. Bioclimate profiles available on the CCCSN website, provide graphical representation of climate and related indices both historically and in the future. Future climate projections are found by applying the closest GCM grid cell change fields (no downscaling) to historical station specific climate data. There are 14 bioclimate profiles on the CCCSN that have freeze thaw days as an index. Results for the 2050s study period project an average of 68 freeze thaw days per year based on an average of the three emission scenarios (SR A1B, SR A2, and SR B1). Probability Scoring The probability score for the future was adjusted from the historical value of 4 to a revised probability score of 2 based on the above noted climate projections and trends, which indicate a substantial decrease in the number of freeze thaw cycles (most notably the bioclimate profiles). As freeze thaw was classified a tier one definition, the probability of its occurrence in relation to the historical average was considered. With the bioclimate profiles indicating such a large variation (decrease) from existing (i.e. 68 cycles from 85 cycles), it was decided that decreasing the probably score by 2 was justified Extreme Heavy Rain Definition For the purposes of this study, extreme heavy rain was defined as the number of days, in a given year, that experienced rainfall greater than or equal to 125mm within a 24 hour period. Although rainfall warnings are issued by Environment Canada in the warm season when 50mm or more is expected to fall within 12 hours (MSC Ontario Region, 2009e), a threshold of 125mm within a 24 hour period was chosen to represent an extreme rainfall event previously experienced with known results. This parameter is a tier two definition Historical Climate Findings Daily rainfall data for Toronto Pearson International Airport, obtained from Environment Canada s Climate Data Online (Environment Canada, 2008), was analyzed for the occurrence of heavy rain based on the above definition. It was determined that throughout the entire period of record from (76 years) there was one occurrence of heavy rain on July 8th, 2013, where 126mm of rain fell within a 24 hour period. This translates to an average occurrence of per year (1/76). Frequency analysis identifies that event as 1:100 year event. Probability Scoring Based on the findings above, (days per year with rainfall greater than or equal to 125mm within a 24 hour period) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 1, with an improbable/highly unlikely chance of occurrence. Page 14 of 34

135 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Trends Vincent and Mekis (2004) showed a significant decrease in the intensity of rain (ratio between annual total rainfall amount and the number of days with rain) in southern Canada from 1950 to 2001, however concluded that there were no consistent changes in the highest 5 day maximum. A subsequent study by Vincent and Mekis (2006) supported this finding and showed that the number of days with rainfall (days with rain greater than trace amounts) increased from 1950 to 2003 throughout southern Canada. They also found a decrease in a simple daily intensity index (annual rainfall divided by the number of days with rain). Another paper by Hogg (1996) found an insignificant positive trend in extreme rainfall (undefined based on station extremes) over the last 60 to 90 years for all regions in Canada. Zhang et al. (2000) found that the total precipitation in southern Canada increased by 12% from 1900 to 1998, while Zhang et al. (2001) found no identifiable trends in extreme precipitation (90th percentile, maximum and 20 year return values of annual daily precipitation) over the same period. A paper written by Cheng, Li, G., and Li, Q. (2007a) analysed the number of days in the warm season (April to November) with rainfall related weather types and found that for Toronto, the number of days increased by 8.2 days over the period 1958 to Trend information showed a decrease in a simple daily rainfall intensity indicator, but an increase in the number of days with rain. It is noted that some of these studies are not specific to the Toronto area and do not define heavy rain the same as this report (i.e. the number of days that experience rainfall greater than or equal to 125mm within a 24 hour period) Climate Projections Findings Based on a review of various relevant articles, Chiotti and Lavender (2008) deduced that the majority of GCM models project an increase in precipitation within the next 20 to 50 years, which is expected to be more intense and more frequent. Kharin et al. (2007) concluded that relative changes in precipitation intensity extremes generally exceed relative changes in annual mean precipitation. Christensen et al., (2007, IPCC) found that in southern Canada precipitation is likely to increase in winter and spring but decrease in summer. Furthermore, Meehl et al., (2007, IPCC) indicated that global precipitation is expected to be concentrated in more intense events that are less frequent with more days between rainfalls. The model outputs available on the CCCSN for the grid cell encompassing Toronto project an increase in the annual mean total precipitation by 5.12% by the 2050s. The model outputs also project that days with precipitation greater than the 95th percentile will increase by 2.35%. Probability Scoring The probability score for the future was adjusted from the historical value of 1 to a revised probability score of 2 based on the above noted climate projections. Although trends do not show an increase in daily precipitation extremes, some future projections suggest an increase in the frequency of extreme daily precipitation events. Page 15 of 34

136 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Heavy Rain Definition For the purposes of this study, heavy rain was defined as the number of days, in a given year, that experienced rainfall greater than or equal to 50mm within a 24 hour period. Although rainfall warnings are issued by Environment Canada in the warm season when 50mm or more is expected to fall within 12 hours (MSC Ontario Region, 2009e), a 24 hour period was chosen for this parameter s definition as data was more readily available and it was considered to still represent extreme or phenomenal rainfall conditions. This parameter is a tier two definition Historical Climate Findings Daily temperature data for Toronto Pearson International Airport, obtained from Environment Canada s CDCD program (Environment Canada, 2007), was analyzed for the occurrence of heavy rain from 1971 to 2000 based on the above definition. It was determined that 14 heavy rain episodes occurred during this 30 year period. This translates to an average of 0.47 occurrences per year (14/30). Probability Scoring Based on the findings above, 0.47 (days per year with rainfall greater than or equal to 50mm within a 24 hour period) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 4, with a moderate/possible chance of occurrence Trends Vincent and Mekis (2004) showed a significant decrease in the intensity of rain (ratio between annual total rainfall amount and the number of days with rain) in southern Canada from 1950 to 2001, however concluded that there were no consistent changes in the highest 5 day maximum. A subsequent study by Vincent and Mekis (2006) supported this finding and showed that the number of days with rainfall (days with rain greater than trace amounts) increased from 1950 to 2003 throughout southern Canada. They also found a decrease in a simple daily intensity index (annual rainfall divided by the number of days with rain). Another paper by Hogg (1996) found an insignificant positive trend in extreme rainfall (undefined based on station extremes) over the last 60 to 90 years for all regions in Canada. Zhang et al. (2000) found that the total precipitation in southern Canada increased by 12% from 1900 to 1998, while Zhang et al. (2001) found no identifiable trends in extreme precipitation (90th percentile, maximum and 20 year return values of annual daily precipitation) over the same period. A paper written by Cheng, Li, G., and Li, Q. (2007a) analysed the number of days in the warm season (April to November) with rainfall related weather types and found that for Toronto, the number of days increased by 8.2 days over the period 1958 to Trend information showed a decrease in a simple daily rainfall intensity indicator, but an increase in the number of days with rain. It is noted that some of these studies are not specific to the Toronto area and do not define heavy rain the same as this definition (i.e. the number of days that experience rainfall greater than or equal to 50mm within a 24 hour period). Page 16 of 34

137 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Climate Projections Findings Based on a review of various relevant articles, Chiotti and Lavender (2008) deduced that the majority of GCM models project an increase in precipitation within the next 20 to 50 years, which is expected to be more intense and more frequent. Kharin et al. (2007) concluded that relative changes in precipitation intensity extremes generally exceed relative changes in annual mean precipitation. Christensen et al., (2007, IPCC) found that in southern Canada precipitation is likely to increase in winter and spring but decrease in summer. Furthermore, Meehl et al., (2007, IPCC) indicated that global precipitation is expected to be concentrated in more intense events that are less frequent with more days between rainfalls. The model outputs available on the CCCSN for the grid cell encompassing Toronto project an increase in the annual mean total precipitation by 5.12% by the 2050s. The model outputs also project that days with precipitation greater than the 95th percentile will increase by 2.35%. Probability Scoring The probability score for the future was adjusted from the historical value of 4 to a revised probability score of 5 based on the above noted climate projections. Although trends do not show an increase in daily precipitation extremes, some future projections suggest an increase in the frequency of extreme daily precipitation events Heavy 5-Day Total Rainfall Definition For the purposes of this study, heavy 5 day total rainfall was defined as a period of 5 days with a total rainfall exceeding 100mm. The number of heavy 5 day total rainfall occurrences within a given year was considered. A 5 day period was chosen because it agreed with the CCCSN 5 day maximum rainfall index used for future projections and was determined to be reflective of prolonged or persistent rain. The 100mm total rainfall threshold was chosen subjectively, to represent a substantial amount of rainfall in a relatively short period of time. This parameter is a tier two definition Historical Climate Findings Daily rainfall data for Toronto Pearson International Airport, obtained from Environment Canada s Climate Data Online (Environment Canada, 2008), was analyzed for the occurrence of heavy 5 day total rainfall from 1938 to 2008 based on the above definition. It is noted that this is a departure from the time frame previously referenced, however this parameter was deemed to be better represented by a longer time frame (e.g. allowed for the inclusion of Hurricane Hazel). The total rainfall for every 5 day period from 1938 to 2008 was identified. The analysis was conducted in such a way that no one day rainfall amount was included in more than one 5 day total. During the 71 year time frame, five occurrences of a 5 day total rainfall exceeding 100mm were identified. This translates to an average of 0.07 occurrences per year (5/71). Page 17 of 34

138 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Probability Scoring Based on the findings above, 0.07 (heavy 5 day total rainfall occurrences per year) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 2, with a remote chance of occurrence Trends Trends in rainfall extremes were examined in Section of this chapter. Even though trends show a decrease in rainfall intensity, they show an increase in the number of days with rain. The Vincent and Mekis study (2004) was determined to be the most applicable to this section. They found a significant decrease in the intensity of rainfall events from 1950 to 2001 and no consistent changes in the highest 5 day maximum Climate Projections Findings Projections in precipitation were examined in Section , Findings, identifying increases in precipitation and frequency of extremes. Projection information specific to 5 day total rainfall was identified in the CCCSN (for Toronto grid cell) with model outputs expressing a magnitude of change for the maximum 5 day total precipitation. For this index, an increase of 5.10mm was projected for the 2050s. Probability Scoring The probability score for the future was adjusted from the historical value of 2 to a revised probability score of 3 based on the above noted climate projections and trends. Trends show an increase in the number of days with rain, while future projections indicate that there will likely be an increase in precipitation with a potential increase in the frequency of extreme precipitation events. In addition, based on the CCCSN model output discussed above, the magnitude of maximum 5 day total precipitation is expected to increase. It is noted that this does not necessarily relate directly to the frequency of 5 day maximum rainfall exceeding 100mm, however one might assume that the potential for this to occur will increase Winter Rain Definition For the purposes of this study, winter rain was defined as the number of days, in a given year, where greater than or equal to 25mm of rain fell throughout the months January, February, and March (JFM). This definition was chosen because it related well to Environment Canada s rainfall warning in the winter season, which is issued when greater than 25mm is expected to fall within 24 hours, if the ground is frozen or covered by snow (MSC Ontario Region, 2009e). It was assumed for this study that rain falling during JFM will be on ground that is frozen or snow covered. These conditions could potentially result in significantly greater runoff than rainfall events during other seasons, and therefore were considered separately and in addition to overall annual changes to rainfall characteristics as described by the above parameters. This parameter is a tier two definition. Page 18 of 34

139 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Historical Climate Findings Daily precipitation data for Toronto Pearson International Airport, obtained from Environment Canada s CDCD program (Environment Canada, 2007), was analyzed for the occurrence of winter rain from 1971 to 2000 based on the above definition. It was determined that 10 heavy winter rain events of greater than 25mm occurred during the 30 year study period. This translates to an average of 0.33 occurrences per year (10/30). Probability Scoring Based on the findings above, 0.33 (days per year with winter rain) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 4, with a moderate/possible chance of occurrence Trends Trends previously examined established that there is an increasing annual trend in the amount of rainfall. Zhang et al. (2000) examined total precipitation trends seasonally for southern Canada for the years 1900 to 1998 and found an increasing trend in winter and autumn, a decreasing trend in the spring and no trend in the summer. The trends in this study do not distinguish between rain and snow as precipitation. Zhang et al. (2000) found a non significant increase in the ratio of snowfall to total precipitation for the years 1900 to 1998 for southern Canada. However, for the time period of , they found a decrease in the ratio between snowfall and total precipitation. Similarly, for the time period , Vincent and Mekis (2004) found that, the ratio of snowfall to total precipitation decreased in southern Canada, indicating more winter rain. In addition, the Canadian Council of Ministers of the Environment (CCME, 2003) identified that in southern Canada, over the past 50 years, there has been a higher proportion of precipitation falling as rain. It is noted that these studies are not specific to the Toronto area and do not define winter rain the same as this report (i.e. the number of days where 25mm or more of rain fell throughout the months January, February and March) Climate Projections Findings Christensen et al., (2007, IPCC) found that in southern Canada precipitation is likely to increase in winter and spring but decrease in summer. Furthermore, they indicated that the length of the snow season is expected to decrease. Projected increases in minimum temperatures may create conditions that are too warm for precipitation to fall as snow, thus resulting in more precipitation as rain throughout Canada (CCME, 2003). It is noted that this does not necessarily translate to more than 25mm of rain falling in January, February and March (as per this report s definition of winter rain). Probability Scoring The probability score for the future was left unchanged from the historical value of 4 based on the following rationale. Although historical trend and projection information show a likely increase in the amount of rainfall during the winter season, other considerations counteract (lessen) this parameter s impact. Typically winter rain presents challenges when falling on frozen or snow covered ground as the potential for run off is greatly increased. However, in the future, increased temperatures are likely to Page 19 of 34

140 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections result in a reduction of frozen or snow covered ground, thus lessening the potential for significant runoff issues. As such, for the purposes of this study, these factors were deemed to cancel one another out as the same warm temperatures that contribute to rain falling during the winter (rather than snow) also contribute to the reduced potential for, and magnitude of frozen or snow covered ground Freezing Rain Definition Freezing rain is rain or drizzle which falls as liquid but freezes upon contact with the surface or a cold object, forming a coating of ice upon these surfaces (MSC Ontario Region, 2009g). For the purposes of this study, freezing rain was defined as the average number of days within a given year, where freezing rain or drizzle, equal to or greater than 0.2mm in diameter (MSC Ontario Region, 2009g), occurred. This parameter is a tier one definition Historical Climate Findings Data obtained from Environment Canada s Ontario Hazards website (Environment Canada. Icestorm Dayswithfrzprecip e.xls) indicated that the Toronto Pearson International Airport experienced an average of 8.8 days per year with freezing precipitation (rain and drizzle) during the years based on the above definition. Probability Scoring As freezing rain was established as a tier one definition, the standardized probability scoring process was employed. Based on the assumption that 0.5 represents the probability that the historical average number of freezing rain events (8.8) would occur in a given year, established ranges in Table A 1 indicate that a probability score of 4 be ascribed, with a moderate/probable chance of occurrence Trends A study by Klaassen et al. (2003) identified a non significant decreasing trend in the total number of seasonal freezing rain hours and days for Toronto Pearson International Airport during the years 1953 to Climate Projections Findings A study by Cheng et al., (2007b), involving downscaling of selected global climate model output using a statistical synoptic weather typing approach, indicated that freezing rain events in the Toronto region could increase by 40% by the 2050s for December to February, while the warmer months (defined as November, March and April) could experience a decrease of approximately 10% in freezing rain by the 2050s. This results in an annual increase of approximately 30% with 95% confidence (Cheng et al., 2007b). Page 20 of 34

141 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Probability Scoring The probability score for the future was adjusted from the historical value of 4 to a revised probability score of 6 based on the above noted climate projections. As freezing rain was classified as a tier one definition, the probability of its occurrence in relation to its historical average was considered. Findings from the Cheng, et al. study (2007b), indicating an increase in freezing rain of 30% by the 2050s, were considered substantial enough to justify increasing the probability score by Ice Storm Definition For the purposes of this study, ice storms were defined as daily freezing rain amounts of 25mm or more (Klaassen et al., 2003). The number of ice storm occurrences within a given year was considered. This parameter is a tier two definition Historical Climate Findings Based on the above definition, Table 7 from the Klaassen et al. (2003) study was analyzed to understand the occurrences of major freezing rain events affecting the general Toronto area. 11 regional storms were identified between the years 1844 and This translates to an average of 0.07 ice storms per year (11/159). Probability Scoring Based on the findings above, 0.07 (days with freezing rain amounts of 25 mm or more) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 2, with a remote chance of occurrence Trends A study by Klaassen et al. (2003) identified a non significant decreasing trend in the total number of seasonal freezing rain hours and days for Toronto Pearson International Airport during the years 1953 to It is noted that this is not necessarily representative of ice storm events with greater than or equal to 25 mm of freezing rain Climate Projections Findings Freezing rain was predicted to increase by approximately 30% by the 2050s for the Toronto area. In addition, Klaassen (2008a) indicates that the greatest percent change of freezing rain will likely occur for long duration events. Probability Scoring The probability score for the future was adjusted from the historical value of 2 to a revised probability score of 3 based on the above noted climate projections, which indicates an increase in freezing rain and an increase in the longer duration of freezing rain events. Page 21 of 34

142 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Heavy Snow Definition For the purposes of this study, heavy snow was defined as the number of days, in a given year, with greater than or equal to 10 cm of snowfall. The 10 cm snowfall threshold was chosen subjectively, to represent a substantial amount of snowfall in a day. This parameter is a tier two definition Historical Climate Findings Snowfall data from 1971 to 2000, yielded from the Climate Normals for Toronto Pearson International Airport, is shown in Table A 4 below. On average there were 2 days per year with snowfall exceeding 10 cm and 0 days per year with snowfall exceeding 25 cm. It should be noted that the highest daily snowfall ever recorded at Toronto Pearson International Airport was 39.9cm (February 25th 1965) (Environment Canada, n.d.). Table A 4 Snowfall Results for the Period Description Days/Year Number of days with snowfall >= 10cm 2 Number of days with snowfall >= 25cm 0.0 *(Environment Canada, n.d.) Probability Scoring Based on the findings above, 2 (days per year with heavy snow) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 6, with a probable chance of occurrence Trends Zhang et al. (2000) found a non significant increase in the ratio of snowfall to total precipitation for the years 1900 to 1998 for southern Canada. However, for the time period of , they found a decrease in the ratio between snowfall and total precipitation. Similarly, for the time period , Vincent and Mekis (2004) found that the ratio of snowfall to total precipitation has decreased in southern Canada, indicating less snowfall. In a subsequent paper, Vincent and Mekis (2006) found a significant decrease in the total annual snowfall in the southern regions of Canada during the second half of the 20th century ( ), even though the total annual snowfall increased from 1900s to the 1970s. In addition, the Canadian Council of Ministers of the Environment (CCME, 2003) identified that in southern Canada, over the past 50 years, there has been a smaller proportion of precipitation falling as snow. It is noted that these studies are not specific to the Toronto area and do not define heavy snow the same as this report (i.e. the number of days that experience snowfall greater than or equal to 10cm). Page 22 of 34

143 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Climate Projections Findings Projected increases in minimum temperatures may create conditions that are too warm for precipitation to fall as snow, thus resulting in more precipitation as rain throughout Canada (CCME, 2003). In addition, the snow season length is expected to decrease in most of North America (Christensen et al., 2007, IPCC). It is noted that these projections are generic in nature and do not necessarily accurately reflect the Toronto area. Probability Scoring The probability score for the future was left unchanged from the historical value of 6 based on the fact that limited projection information was available Snow Accumulations Definition For the purposes of this study, snow accumulation was defined as the number of days, in a given year, where 30cm or more of snow exists on the ground. The 30cm snow accumulation threshold was chosen subjectively to represent a substantial amount of snow on the ground. This parameter is a tier two definition Historical Climate Findings Daily snow depth data for Toronto Pearson International Airport, obtained from Environment Canada s Canadian Daily Climate Data program (CDCD) (Environment Canada, 2007), was analyzed for the occurrence of days with snow accumulation from 1971 to 2000 based on the above definition. It was determined that 39 days had snow accumulation during this 30 year period. This translates to an average of 1.3 days per year (39/30). Probability Scoring Based on the findings above, 1.3 (days per year with snow accumulation) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 6, with a probable chance of occurrence Trends No studies specifically analyzing trends of snow accumulation were identified, although related trends in snowfall were established in the articles reviewed Climate Projections Findings Projected increases in minimum temperatures may create conditions that are too warm for precipitation to fall as snow, thus resulting in more precipitation as rain throughout Canada (CCME, 2003). In addition, the snow season length and snow depth is expected to decrease in most of North America. A decrease Page 23 of 34

144 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections in the seasonal snow depth is expected as a result of delayed snowfall in the fall and earlier spring melt (Christensen et al., 2007, IPCC). Scott, McBoyle, and Mills (2003) conducted a study on the skiing industry in southern Ontario, using Horseshoe Ski Resort as a case study. They looked at snowmaking requirements in a warming climate using variables downscaled from 4 general circulation models. Findings indicated that snowmaking requirements were expected to increase by % by the 2020s. The ski season length including current snowmaking technologies is expected to decrease by 0 16% for the 2020s and 7 32% for the 2050s (Scott et al., 2003). Although this study does not relate well to the number of days with 30cm or more of snow on the ground, the findings suggest that having this amount of snow on the ground may become increasingly unlikely. Probability Scoring The probability score for the future was adjusted from the historical value of 6 to a revised probability score of 5 based on the above noted climate projections, which indicate potential decreases in snow depth and available snow on the ground (i.e. inferred from snowmaking requirements for skiing discussed above) Blowing Snow/Blizzard Definition Blizzards are severe weather conditions characterized by high winds and reduced visibility due to falling or blowing snow (Environment Canada, 2002). Due to a lack of information regarding blizzards, blowing snow was used as an indictor of this type of climate event. Blowing snow is defined by Environment Canada as snow particles which are raised by the wind to a sufficient height above the ground such that horizontal visibility is reduced to 9.7 km or less. For the purposes of this study, the average number of days in which blowing snow occurred, within a given year, was considered. This parameter is a tier one definition Historical Climate Findings Data obtained from Environment Canada s Ontario Hazards website indicated that the Toronto Pearson International Airport experienced an average of 7.8 days per year with blowing snow during the years based on the above definition. Probability Scoring As blowing snow/blizzard was established as a tier one definition, the standardized probability scoring process was employed. Based on the assumption that 0.5 represents the probability that the historical average number of blowing snow/blizzard events (7.8) would occur in a given year, established ranges in Table A 1 indicate that a probability score of 4 be ascribed, with a moderate/probable chance of occurrence Trends No studies specifically analyzing trends of blowing snow/blizzard were identified, although trends in snowfall, which have some relation, were established in the articles reviewed. Page 24 of 34

145 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Climate Projections Findings No studies specifically analysing projections of blowing snow/blizzard were identified, although projections related to snowfall and snow depth are discussed in this appendix. Probability Scoring The probability score for the future was left unchanged from the historical value of 4 based on the lack of directly relatable information. Although trends and projections in snowfall and snow accumulation were considered for use as indicators of future blowing snow and blizzard conditions, the component of wind in the definition differentiated this parameter enough such that the team decided not to change the future probability score Lightning Definition Lightning is a sudden electrical discharge from or within a cloud (Rauber, Walsh, & Charlevoix, 2005). For the purposes of this study, lightning was defined as the number of flashes per year per 250 m by 250 m (representing the airport area including essential services). It is noted that limited information regarding lightning was available. This parameter is a tier two definition Historical Climate Findings The Meteorological Service of Canada indicated that there is an average of approximately 200 flashes per year per 100 km 2 in Toronto (Burrows et al, 2002). For the purposes of this study, lightning was considered a threat to the airport if it occurred within 62,500 m 2 (250 m by 250 m, which was deemed representative of the airport area). It is noted that this number of flashes included both cloud to cloud and cloud to ground interactions. Probability Scoring Based on the findings above, this would result in a lightning occurrence of flashes per year within the defined area. This was compared to in the established ranges in Table A 1 and was subsequently ascribed a probability score of 3, with an occasional chance of occurrence Trends No trend information was found for lightning Climate Projection Findings Due to the absence of projections for lightning and the fact that thunderstorms are always accompanied by lightning (MSC Ontario Region, 2005b), it was possible for thunderstorms to be used as indicators of lightning activity. The CCME (2003) indicates that in the future, in Canada, the warm season is expected to get longer thus increasing the risk of severe hot weather events such as thunderstorms. Furthermore, Trapp et al. (2007) projected a net increase in the number of days during the late 21st Century, in which Page 25 of 34

146 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections environmental conditions would be conducive for severe thunderstorms to occur (in the United States of America). This paper acknowledges that the frequency of actual storms is conditional upon convective clouds initiating in these environments. It is noted that this research is not specific to the Toronto area. Probability Scoring The probability score for the future was left unchanged from the historical value of 3 based on the fact that no projection information on lightning was available. The projection information provided on thunderstorms identified above was deemed insufficient to justify changing the probability score Hailstorm Definition Hail is frozen precipitation particles with a diameter greater than 5mm formed from the strong upward motion characteristic of thunderstorms (MSC Ontario Region, 2009d). For the purposes of this study, a hailstorm was defined as the number of days with hail in a given year. This parameter is a tier two definition Historical Climate Findings Data obtained from Environment Canada s Ontario Hazards website indicated that the Toronto Pearson International Airport experienced an average of 1.1 days per year with hail during the years based on the above definition. Probability Scoring Based on the findings above, 1.1 (days per year with hail) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 5, with an often chance of occurrence Trends No trend information was found for hail Climate Projections Findings No projection information was found for hail. Probability Scoring The probability score for the future was left unchanged from the historical value of 5 based on the fact that no projection information on hail was available. Page 26 of 34

147 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Hurricane/Tropical Storm Definition Hurricanes are cyclones of a tropical origin with sustained surface wind speeds of 118km/hour or more (MSC Ontario Region, 2009f). They are classified according to the Saffir Simpson Hurricane Wind Scale. Most hurricanes affecting Canada are passing through a post tropical transition stage or are dissipating (MSC Ontario Region, 2009f). For the purposes of this study, a hurricane/tropical storm was defined as a severe event similar in magnitude (both wind speed and amount of precipitation) to Hurricane Hazel, which resulted in maximum wind speeds of 124km/hour and 285 mm of rain falling in a 48 hour period (MSC Ontario Region, 2009f). The number of hurricanes/tropical storms within a given year was considered. This parameter is a tier two definition. An event similar to Hurricane Hazel was selected because it was agreed to represent an extreme or phenomenal event. It is noted that although storm tracks frequently extend over the Toronto area, to date, they have not caused nearly the same impact as Hurricane Hazel Historical Climate Findings The remnants of Hurricane Hazel passed through the Toronto region on October 15th and 16th, The heaviest rains fell over the Humber watershed, where in the final 12 hours, 212 mm of rain was recorded (MSC Ontario Region, 2009f). During this event severe flooding occurred in both the Don and Humber watersheds (MSC Ontario Region, 2009f). This event caused the worst flooding documented in 200 years (MSC Ontario Region, 2009f). Probability Scoring Based on the findings above, (Hurricane Hazel magnitude hurricanes per year) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 1, with an improbable/highly unlikely chance of occurrence Trends It is difficult to analyse the changes in specific climatic extreme events such as hurricanes, floods, and droughts because these events do not necessarily occur very often and do not happen at the same location (Vincent and Mekis, 2006). Meehl et al. (2007, IPCC) indicated that in the last 30 years there has been an increase in the number of category 4 and 5 hurricanes per year (globally). In addition, Webster et al. (2006), as cited in Bruce (2008b), concluded that the number of Atlantic hurricanes has not increased since the early 1970s; however, the number of category 4 and 5 hurricanes has risen sharply. Kunkel, Pielke, and Changnon (1999) found that there has been a steady and substantial increase in hurricane losses, however no corresponding upward trend in hurricane frequency and intensity were identified. They attributed the observed increase in storm losses to societal exposure. It is noted that no studies were identified that discussed trends in hurricane storm tracks. Furthermore, the studies discussed above are not specific to the Toronto area and do not define hurricanes the same as this report (i.e. Hurricane Hazel). Page 27 of 34

148 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Climate Projections Findings Projections of hurricanes with climate change show few consistent results although most climate models indicate that, in future tropical cyclones, there will likely be an increase in precipitation (including intensity) as well as high wind peaks. Less certain projections indicate that the total number of tropical storms will likely decrease along with the number of weak tropical cyclones (Meehl et al., 2007, IPCC). Emanuel, Sundararajan, and Williams (2008) also showed a decrease in the overall frequency of tropical cyclones with an increase in the number of intense tropical cyclones. Although storm tracks provide important information in evaluating tropical storms, they are still not resolved and regional predictions remain uncertain (Christensen et al., 2007, IPCC). Global predictions indicate a shift in storm tracks in both hemispheres towards the pole by several degrees of latitude (Meehl et al., 2007, IPCC). It is noted that these projections do not necessarily relate to the Toronto area. Probability Scoring The probability score for the future was adjusted from the historical value of 1 to a revised probability score of 2 based on the above noted climate projections and trends, which indicate increases in tropical cyclone intensity and frequency (category 4 and 5), respectively. For the purposes of this study, hurricanes originating from the southern parts of North America are assumed to have a greater possibility of impacting the Toronto area in the future as they are projected to have greater intensities, even though storm tracks have not been resolved in climate models High Wind Definition Wind is the horizontal movement of air relative to the earth s surface (Rauber et al., 2005). For the purposes of this study, high wind was defined as the average number of days (7.2 as described below), in a given year, with wind speeds recorded at greater than or equal to 63 km/hour. This parameter is a tier one definition Historical Climate Findings High wind data from 1971 to 2000, yielded from the Climate Normals for Toronto Pearson International Airport are shown in Table A 5 below. The highest wind speed ever recorded at Toronto Pearson International Airport was 135km/hour (July 1st 1956) (Environment Canada, n.d.). On average, there were 7.2 days per year with a wind speed equal to or exceeding 63km/hour. Page 28 of 34

149 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Table A 5 High Wind Results for the Period Description Appendix A Draft Climate Change Analysis and Projections Days/Year Number of days with a wind speed of >= 63km/hour 7.2 *(Environment Canada, n.d.) Probability Scoring As high wind was established as a tier one definition, the standardized probability scoring process was employed. Based on the assumption that 0.5 represents the probability that the historical average number of high wind events (7.2) would occur in a given year, established ranges in Table A 1 indicate that a probability score of 4 be ascribed, with a moderate/probable chance of occurrence Trends No trend information was found for high wind Climate Projections Findings No projection information was found for high wind Tornado Definition A tornado is a rotating column of air in contact with the ground extending to a cloud base (Rauber et al., 2005). Tornadoes are a product of thunderstorms, although not all thunderstorms produce tornadoes (Kunkel et al., 1999). The intensity of a tornado is ranked according to the Fujita scale, which is a measure of infrastructure damage. F0 tornadoes typically have light winds of 64 to 116 km/hr, F1 tornadoes typically have moderate winds of 117 to 180 km/hr, F2 tornadoes typically have considerable winds of 181 to 252 km/hr, F3 tornadoes typically have severe winds of 253 to 330 km/hr, F4 tornadoes typically have devastating winds of 331 to 417 km/hr, and F5 tornadoes typically have incredible winds of 418 to 509 km/hr (MSC Ontario Region, 2009h). Tornadoes cause considerable damage depending on the severity of the tornado (MSC Ontario Region, 2009h). For the purposes of this study, this parameter was defined as the number of confirmed and probable tornado occurrences in a given year within a defined geographic location (representing the airport area). A subjective search area around the airport was selected. This parameter is a tier two definition Historical Climate Findings The list of confirmed and probable tornadoes in Ontario for the period 1918 to 2003 was downloaded from Environment Canada. This included information on the initial observed touchdown location and strength of each tornado recorded. In order to determine which tornadoes presented threatening conditions for the airport, a more refined search area (by establishing latitudinal and longitudinal references), encompassing the airport area, was required. The boundary reference coordinates used Page 29 of 34

150 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections were ( 79.53, 43.63), ( 79.53, 43.72), ( 79.71, 43.63), ( 79.71, 43.72). Using the list of tornadoes in Ontario (and the related information) the team was able to identify which tornadoes passed through the prescribed search area. The results of this analysis showed that 4 tornadoes occurred in the search area between 1918 and This translates to approximately tornadoes per year (4/86). A full list of the tornadoes that passed through this area and their strength is outlined in Table A 6 below. Table A 6 Tornado Results for the Period Label Longitude Latitude Fujita Scale Date T /20/1958 T /30/1970 T /02/1983 T /17/1988 *Environment Canada Probability Scoring Based on the findings above, (tornadoes per year within prescribed search area) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 1, with an improbable/highly unlikely chance of occurrence Trends It is reported in Climate, Nature, People Indicators of Canada s Changing Climate (CCME 2003) that the number of reported tornadoes has increased over the past century. It is difficult to determine whether this is due to an increasing number of tornadoes occurring or simply an increase in the number of tornadoes being reported (CCME, 2003). A study by Kunkel et al. (1999) concluded that there were no major national (United States) trends in the frequency of thunderstorms, hailstorms and strong tornadoes. It is noted that these studies are not specific to the Toronto area and do not define tornadoes the same as this report with respect to the designated area around the airport Climate Projections Findings The CCME (2003) indicates that the warm season is expected to get longer resulting in an increase in the risk of severe hot weather events such as thunderstorms, hail and tornadoes. However, the unique atmospheric conditions that would create locally damaging storms such as tornadoes and severe thunderstorms are difficult to link to climate change (Trapp et al., 2007). Probability Scoring The probability score for the future was left unchanged from the historical value of 1 based on the fact that no specific projection information on tornadoes was available. Page 30 of 34

151 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Drought/Dry Period Definition A drought is defined as the below average availability of water in the form of precipitation, streamflow, or groundwater flow which is sustained and regionally extensive (Rauber et al., 2005). A meteorological drought is defined as a departure of precipitation from normal for a prolonged period of time (MSC Ontario Region, 2009a). For the purposes of this study, the term drought/dry period was defined as a 10 consecutive dry days, meaning; within a given year, 10 days occurring in a row where no measurable precipitation fell (i.e. greater than 0.2mm). A 10 day period was selected for this parameter as it was agreed to represent a prolonged dry period and had relevant information readily available. This parameter is a tier two definition Historical Climate Findings The number of occurrences of a 10 consecutive dry day period for Toronto Pearson International Airport was obtained from Klaassen et al. s paper on drought in southern Ontario (2008). This paper showed that between 1971 and 2000, there was an average of 7.3% drought/dry day period occurrences for the warm months (defined as May through September). As there are 15 possible occurrences for the warm months (i.e. 150 days), there was determined to be an average of 1.1 drought/dry period occurrences per year (0.073 x 15). Probability Scoring Based on the findings above, 1.1 (drought/dry periods per year) was compared to the established ranges in Table A 1 and was subsequently ascribed a probability score of 5, with an often chance of occurrence Trends Vincent and Mekis (2004) found negative trends (throughout Canada) in the number of maximum consecutive dry days from This finding was supported by their 2006 study, which also showed that, throughout Canada, there was a decrease in the maximum number of consecutive dry days from 1950 to It is noted that these studies are not specific to the Toronto area and do not define drought/dry periods the same as this report (i.e. 10 days occurring in a row where no measurable precipitation fell) Climate Projections Findings Christensen et al., (2007, IPCC) indicates that southern Canada is likely to experience an annual mean precipitation decrease in the summer season. The increased saturation vapour pressure due to increasing temperatures is expected to increase evaporation leading to a possible net drying of the surface (Christensen et al., 2007, IPCC). As a result, droughts associated with summer drying, could increase vegetation die offs (Meehl et al., 2007, IPCC). Furthermore, there is expected to be an increase in the frequency and duration of dry days in the future (globally) (Meehl et al., 2007, IPCC). IPCC recognized climate model outputs available on the CCCSN, project an increase in the maximum number of consecutive dry days by 1.70 days for the grid cell encompassing the Toronto area. Page 31 of 34

152 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Probability Scoring The probability score for the future was adjusted from the historical value of 5 to a revised probability score of 6 based on the above noted climate projections, which indicates an increase in the maximum number of consecutive dry days for Toronto. Although this projected increase does not necessarily mean that the 10 consecutive dry days would be surpassed (i.e. this study s definition of drought/dry period), it was assumed that the potential for this to occur would increase. It is noted that the historical trends for drought/dry period do not support the projected increase Heavy Fog Definition Fog is defined as a suspension of very small water droplets that reduces the visibility (horizontally) to less than 1km (MSC Ontario Region, 2009c). Heavy fog occurs when the visibility is reduced to less than 0.4km (MSC Ontario Region, 2009c). Dense fog is characterised by zero visibility (MSC Ontario Region, 2009c). For the purposes of this study, heavy fog was defined as the average number of hours, in a given year, during which the visibility is reduced to zero kilometres (due to presence of fog). This criterion was chosen as it represented the densest fog conditions for which existing data was available. This parameter is a tier one definition Historical Climate Findings Data obtained from Environment Canada s Ontario Hazards website indicated that the Toronto Pearson International Airport experienced an average of 15 hours of heavy fog (visibility reduced to zero kilometres) per year during the years based on the above definition. Probability Scoring As heavy fog was established as a tier one definition, the standardized probability scoring process was employed. Based on the assumption that 0.5 represents the probability that the historical average number of heavy fog events (15 hours) would occur in a given year, established ranges in Table A 1 indicate that a probability score of 4 be ascribed, with a moderate/probable chance of occurrence Trends A study of fog (Muraca et al., 2001) based on data from , found that there was a decreasing trend in the number of days with fog (less than 1 km). This was found consistently at stations across Canada. The reduction in fog events ranged from 20% to 40%. It is noted that this study was not specific to the Toronto area and may not have defined heavy fog the same as this report (i.e. the average number of hours in a given year during which the visibility is reduced to zero kilometres) Climate Projections Findings No projection information was found for heavy fog. Page 32 of 34

153 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Appendix A Draft Climate Change Analysis and Projections Probability Scoring The probability score for the future was left unchanged from the historical value of 4 based on the fact that no projection information on heavy fog was available Summary of Findings A summary of the historical and future probability scores is provided in Table A 7. Table A 7 Probability Scoring Summary Category Climate Parameter Definitions High Temperature Ex. 'P' Fu. 'P' Day(s) with a max. temp exceeding 35 C 4 5 Temperature Wind Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Day(s) with a min. temp below -30 C 3 2 Three or more consecutive days >32 C 4 5 Three or more consecutive days with min temp. <-20 C and max temp. < -10 C 3 2 Daily temp. variation of more than 25 C or more freeze-thaw cycles within one year or more frost days within one year or more hours with visibility <0km within one year or more days with max. winds of >=63km/hr in one year 4 4 Vortex extending upward from the earth's surface at least as far as cloud base (occurring near site) 1 1 Extreme Heavy Rainfall Days with rainfall > 125mm 1 2 Precipitation Heavy Rainfall Rain (Frequency) Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Days with rainfall > 50mm or more days of >10mm of rain within one year 4 5 A five day period receiving > 100mm of rainfall 2 3 Greater than 25mm of rain falling during January, February and March 4 4 Page 33 of 34

154 Toronto Pearson Infrastructure Vulnerability Assessment To Climate Change Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Appendix A Draft Climate Change Analysis and Projections 9 or more days with freezing rain in one year 4 6 Severe Freezing Rain events or more days with blowing snow in one year 4 4 Days with snowfall >10cm or more consecutive days with a snow depth of >30cm 6 5 Days with precipitation falling as ice particles (dia. > 5mm) 5 5 Other Acid Rain Precipitation with ph of < or more days with measureable Wet Days rainfall >0.2mm in one year 4 5 Lightning Hurricane / Tropical Storms Drought/Dry Periods lightning strikes on the airport property within one year 3 3 Cyclones of a tropical origin with sustained surface wind speeds >63km/hr consecutive days with <0.2mm of precipitation 5 6 Dust Storm Visibility <1km for more than an hour 2 2 The following summary points can be observed from Table A 7: The probability scores changed (increased/decreased) by no more than a score of 2 The highest probability score increase was for the freezing rain climate parameter, which increased from a current probability score of 4 to a future probability score of 6 The highest probability score decrease was for the freeze thaw climate parameter, which decreased from a current probability score of 4 to a future probability score of 2 It is important to note that the climate parameters and associated probability scores were applied consistently across all infrastructure components. Page 34 of 34

155 Toronto Pearson Infrastructure Vulnerability Assessment Appendix B Risk Assessment Matrices

156 6B Pond - Existing Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Records Security Fencing Highway Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Vegetated Pond Berm Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Stormwater inlets Outlet pipe Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Fence Page 1 of 96

157 6B Pond - Existing Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Records Security Fencing Highway Detention Basin Vegetated Pond Berm Inlet/Outlet Structures Stormwater inlets Outlet pipe Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Fence Page 2 of 96

158 6B Pond - Future Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Records Security Fencing Highway Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Vegetated Pond Berm Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Stormwater inlets Outlet pipe Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Fence Page 3 of 96

159 6B Pond - Future Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Records Security Fencing Highway Detention Basin Vegetated Pond Berm Inlet/Outlet Structures Stormwater inlets Outlet pipe Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Fence Page 4 of 96

160 6B Pond - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Records Security Fencing Highway Detention Basin Vegetated Pond Berm Inlet/Outlet Structures Stormwater inlets Outlet pipe Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Fence Page 5 of 96

161 6B Pond - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Records Security Fencing Highway Detention Basin Vegetated Pond Berm Inlet/Outlet Structures Stormwater inlets Outlet pipe Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Fence Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 6 of 96

162 Aeroquay Facility - Existing Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site On site access to Outfall Records Detention Basin Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Reinforced Concrete tank (irrigation tank) Mechanical Room Control Room - structure only Inlet/Outlet Structures Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Inlet mm Outlet #1 from separator - 300mm Bypass Outlet from tank - 600mm Concrete weir - Diversion Chamber Aeroquay Outfall mm fibreglass pipe Mechanical systems Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R oil/water separator sluice gate acuator into separator sluice gate acuator into irrigation tank sluice gate acuator - bypass Electric power supply Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Electrical Panel lighting - Electrical Room lighting - high sodium lights (tank) Control and monitoring systems Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Gas Detection System PLC/SCADA System Fire Alarm Level Indicators Communications Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Hardwire Phone Two-way radio Cellular Phone Safety systems Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Page 7 of 96

163 Aeroquay Facility - Existing Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site On site access to Outfall Records Detention Basin Reinforced Concrete tank (irrigation tank) Mechanical Room Control Room - structure only Inlet/Outlet Structures Inlet mm Outlet #1 from separator - 300mm Bypass Outlet from tank - 600mm Concrete weir - Diversion Chamber Aeroquay Outfall mm fibreglass pipe Mechanical systems oil/water separator sluice gate acuator into separator sluice gate acuator into irrigation tank sluice gate acuator - bypass Electric power supply Electrical Panel lighting - Electrical Room lighting - high sodium lights (tank) Control and monitoring systems Gas Detection System PLC/SCADA System Fire Alarm Level Indicators Communications Hardwire Phone Two-way radio Cellular Phone Safety systems Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Page 8 of 96

164 Aeroquay Facility - Future Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site On site access to Outfall Records Detention Basin Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Reinforced Concrete tank (irrigation tank) Mechanical Room Control Room - structure only Inlet/Outlet Structures Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Inlet mm Outlet #1 from separator - 300mm Bypass Outlet from tank - 600mm Concrete weir - Diversion Chamber Aeroquay Outfall mm fibreglass pipe Mechanical systems Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R oil/water separator sluice gate acuator into separator sluice gate acuator into irrigation tank sluice gate acuator - bypass Electric power supply Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Electrical Panel lighting - Electrical Room lighting - high sodium lights (tank) Control and monitoring systems Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Gas Detection System PLC/SCADA System Fire Alarm Level Indicators Communications Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Hardwire Phone Two-way radio Cellular Phone Safety systems Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Page 9 of 96

165 Aeroquay Facility - Future Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site On site access to Outfall Records Detention Basin Reinforced Concrete tank (irrigation tank) Mechanical Room Control Room - structure only Inlet/Outlet Structures Inlet mm Outlet #1 from separator - 300mm Bypass Outlet from tank - 600mm Concrete weir - Diversion Chamber Aeroquay Outfall mm fibreglass pipe Mechanical systems oil/water separator sluice gate acuator into separator sluice gate acuator into irrigation tank sluice gate acuator - bypass Electric power supply Electrical Panel lighting - Electrical Room lighting - high sodium lights (tank) Control and monitoring systems Gas Detection System PLC/SCADA System Fire Alarm Level Indicators Communications Hardwire Phone Two-way radio Cellular Phone Safety systems Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Y / N P S R Page 10 of 96

166 Aeroquay Facility - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site On site access to Outfall Records Detention Basin Reinforced Concrete tank (irrigation tank) Mechanical Room Control Room - structure only Inlet/Outlet Structures Inlet mm Outlet #1 from separator - 300mm Bypass Outlet from tank - 600mm Concrete weir - Diversion Chamber Aeroquay Outfall mm fibreglass pipe Mechanical systems oil/water separator sluice gate acuator into separator sluice gate acuator into irrigation tank sluice gate acuator - bypass Electric power supply Electrical Panel lighting - Electrical Room lighting - high sodium lights (tank) Control and monitoring systems Gas Detection System PLC/SCADA System Fire Alarm Level Indicators Communications Hardwire Phone Two-way radio Cellular Phone Safety systems Page 11 of 96

167 Aeroquay Facility - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site On site access to Outfall Records Detention Basin Reinforced Concrete tank (irrigation tank) Mechanical Room Control Room - structure only Inlet/Outlet Structures Inlet mm Outlet #1 from separator - 300mm Bypass Outlet from tank - 600mm Concrete weir - Diversion Chamber Aeroquay Outfall mm fibreglass pipe Mechanical systems oil/water separator sluice gate acuator into separator sluice gate acuator into irrigation tank sluice gate acuator - bypass Electric power supply Electrical Panel lighting - Electrical Room lighting - high sodium lights (tank) Control and monitoring systems Gas Detection System PLC/SCADA System Fire Alarm Level Indicators Communications Hardwire Phone Two-way radio Cellular Phone Safety systems Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 12 of 96

168 Carlingview Facility - Existing Risk Temperature Wind Precipitation Infrastructure Response Considerations High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility On site access (including hatches) Gate Access (security key or ticket machine) Leased Parking Lot Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Reinforced Concrete Tanks (1 & 2) Inlet/Outlet structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Diversion Vaults (1 & 2) Bypass inlet mm Bypass outlet #1 to tank mm Bypass Outlet #2 to storm mm Inlet from tank mm Weir plates Concrete weirs Low flow channel Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Oil/water separator concrete block building Ventillation System (exhaust + goosenecks) Oil/water separator All electronic controled actuators All manual actuators Sluice gate w/ electronic control acuator Sluice gate - manual Potable water lines (tank, separator) Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Concrete block electrical building Lighting - High sodium lights (tank) Lighting - Electrical room Electrical Distribution Panel Backup Power Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Gas Detection System PLCS/SCADA System Fire Alarm Level Indicators Flow Meters Pump controls(sample & sump) Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Phone Line (alarms + phone) Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Safety equipment (eg life preserver, eye wash station) Interior safety structures (railings/staircases/ladders) Page 13 of 96

169 Carlingview Facility - Existing Risk Precipitation Other Infrastructure Response Considerations Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility On site access (including hatches) Gate Access (security key or ticket machine) Leased Parking Lot Records Detention Basin Reinforced Concrete Tanks (1 & 2) Inlet/Outlet structures Diversion Vaults (1 & 2) Bypass inlet mm Bypass outlet #1 to tank mm Bypass Outlet #2 to storm mm Inlet from tank mm Weir plates Concrete weirs Low flow channel Mechanical systems Oil/water separator concrete block building Ventillation System (exhaust + goosenecks) Oil/water separator All electronic controled actuators All manual actuators Sluice gate w/ electronic control acuator Sluice gate - manual Potable water lines (tank, separator) Electric power supply Concrete block electrical building Lighting - High sodium lights (tank) Lighting - Electrical room Electrical Distribution Panel Backup Power Control and monitoring systems Gas Detection System PLCS/SCADA System Fire Alarm Level Indicators Flow Meters Pump controls(sample & sump) Communications Two-way radio Cellular Phone Phone Line (alarms + phone) Safety systems Safety equipment (eg life preserver, eye wash station) Interior safety structures (railings/staircases/ladders) Page 14 of 96

170 Carlingview Facility - Future Risk Temperature Wind Precipitation Infrastructure Response Considerations High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility On Site Access (including hatches) Gate Access (security key or ticket machine) Leased Parking Lot Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Reinforced Concrete Tanks (1 & 2) Inlet/Outlet structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Diversion Vaults (1 & 2) Bypass inlet mm Bypass outlet #1 to tank mm Bypass Outlet #2 to storm mm Inlet from tank mm Weir plates Concrete weirs Low flow channel Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Oil/water separator concrete block building Ventillation System (exhaust + goosenecks) Oil/water separator All electronic controled actuators All manual actuators Sluice gate w/ electronic control acuator Sluice gate - manual Potable water lines (tank, separator) Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Concrete block electrical building Lighting - High sodium lights (tank) Lighting - Electrical room Electrical Distribution Panel Backup Power Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Gas Detection System PLCS/SCADA System Fire Alarm Level Indicators Flow Meters Pump controls(sample & sump) Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Phone Line (alarms + phone) Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Safety equipment (eg life preserver, eye wash station) Interior safety structures (railings/staircases/ladders) Page 15 of 96

171 Carlingview Facility - Future Risk Precipitation Other Infrastructure Response Considerations Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility On Site Access (including hatches) Gate Access (security key or ticket machine) Leased Parking Lot Records Detention Basin Reinforced Concrete Tanks (1 & 2) Inlet/Outlet structures Diversion Vaults (1 & 2) Bypass inlet mm Bypass outlet #1 to tank mm Bypass Outlet #2 to storm mm Inlet from tank mm Weir plates Concrete weirs Low flow channel Mechanical systems Oil/water separator concrete block building Ventillation System (exhaust + goosenecks) Oil/water separator All electronic controled actuators All manual actuators Sluice gate w/ electronic control acuator Sluice gate - manual Potable water lines (tank, separator) Electric power supply Concrete block electrical building Lighting - High sodium lights (tank) Lighting - Electrical room Electrical Distribution Panel Backup Power Control and monitoring systems Gas Detection System PLCS/SCADA System Fire Alarm Level Indicators Flow Meters Pump controls(sample & sump) Communications Two-way radio Cellular Phone Phone Line (alarms + phone) Safety systems Safety equipment (eg life preserver, eye wash station) Interior safety structures (railings/staircases/ladders) Page 16 of 96

172 Carlingview Facility - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility On site access (including hatches) Gate Access (security key or ticket machine) Leased Parking Lot Records Detention Basin Reinforced Concrete Tanks (1 & 2) Inlet/Outlet structures Diversion Vaults (1 & 2) Bypass inlet mm Bypass outlet #1 to tank mm Bypass Outlet #2 to storm mm Inlet from tank mm Weir plates Concrete weirs Low flow channel Mechanical systems Oil/water separator concrete block building Ventillation System (exhaust + goosenecks) Oil/water separator All electronic controled actuators All manual actuators Sluice gate w/ electronic control acuator Sluice gate - manual Potable water lines (tank, separator) Electric power supply Concrete block electrical building Lighting - High sodium lights (tank) Lighting - Electrical room Electrical Distribution Panel Backup Power Control and monitoring systems Gas Detection System PLCS/SCADA System Fire Alarm Level Indicators Flow Meters Pump controls(sample & sump) Communications Two-way radio Cellular Phone Phone Line (alarms + phone) Safety systems Safety equipment (eg life preserver, eye wash station) Interior safety structures (railings/staircases/ladders) Page 17 of 96

173 Carlingview Facility - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility On site access (including hatches) Gate Access (security key or ticket machine) Leased Parking Lot Records Detention Basin Reinforced Concrete Tanks (1 & 2) Inlet/Outlet structures Diversion Vaults (1 & 2) Bypass inlet mm Bypass outlet #1 to tank mm Bypass Outlet #2 to storm mm Inlet from tank mm Weir plates Concrete weirs Low flow channel Mechanical systems Oil/water separator concrete block building Ventillation System (exhaust + goosenecks) Oil/water separator All electronic controled actuators All manual actuators Sluice gate w/ electronic control acuator Sluice gate - manual Potable water lines (tank, separator) Electric power supply Concrete block electrical building Lighting - High sodium lights (tank) Lighting - Electrical room Electrical Distribution Panel Backup Power Control and monitoring systems Gas Detection System PLCS/SCADA System Fire Alarm Level Indicators Flow Meters Pump controls(sample & sump) Communications Two-way radio Cellular Phone Phone Line (alarms + phone) Safety systems Safety equipment (eg life preserver, eye wash station) Interior safety structures (railings/staircases/ladders) Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 18 of 96

174 Etobicoke Creek Facility - Existing Risk Temperature Wind Precipitation Infrastructure Response Considerations High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (eg. Flood level warning) Equipment for facility inspection/maintenance Access to facility On-site access Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Vegetated detention cells Inlet/Outlet structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Concrete spillway Gabian basket retaining structure Diversion Chambers Low flow channel High flow channel Inlet and outlet pipes (150mm mm) Ditches Outlet to storm (600mm) Outlet to sanitary (600mm) Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Oil/water seperator Motorized acuators Sampler pump Sluice gates (manual and motorized) HVAC in buildings Potable water line with backflow preventor Ventilation system (exhaust) Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electrical panel Lighting Electrical building Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Gas monitoring system PLCS/SCADA System Fire alarm Level sensor Pump control Flow meter Dialar Alarm Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Phone Line (alarms + Phone) Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Chainlink security fence Safety equipment Safety structures (ladders, railings, platforms) Page 19 of 96

175 Etobicoke Creek Facility - Existing Risk Precipitation Other Infrastructure Response Considerations Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (eg. Flood level warning) Equipment for facility inspection/maintenance Access to facility On-site access Records Detention Basin Vegetated detention cells Inlet/Outlet structures Concrete spillway Gabian basket retaining structure Diversion Chambers Low flow channel High flow channel Inlet and outlet pipes (150mm mm) Ditches Outlet to storm (600mm) Outlet to sanitary (600mm) Mechanical systems Oil/water seperator Motorized acuators Sampler pump Sluice gates (manual and motorized) HVAC in buildings Potable water line with backflow preventor Ventilation system (exhaust) Electric power supply Electrical panel Lighting Electrical building Control and monitoring systems Gas monitoring system PLCS/SCADA System Fire alarm Level sensor Pump control Flow meter Dialar Alarm Communications Two-way radio Cellular Phone Phone Line (alarms + Phone) Safety systems Chainlink security fence Safety equipment Safety structures (ladders, railings, platforms) Page 20 of 96

176 Etobicoke Creek Facility - Future Risk Temperature Wind Precipitation Infrastructure Response Considerations High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (eg. Flood level warning) Equipment for facility inspection/maintenance Access to facility On-site access Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Vegetated detention cells Inlet/Outlet structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Concrete spillway Gabian basket retaining structure Diversion Chambers Low flow channel High flow channel Inlet and outlet pipes (150mm mm) Ditches Outlet to storm (600mm) Outlet to sanitary (600mm) Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Oil/water seperator Motorized acuators Sampler pump Sluice gates (manual and motorized) HVAC in buildings Potable water line with backflow preventor Ventilation system (exhaust) Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electrical panel Lighting Electrical building Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Gas monitoring system PLCS/SCADA System Fire alarm Level sensor Pump control Flow meter Dialar Alarm Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Phone Line (alarms + Phone) Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Chainlink security fence Safety equipment Safety structures (ladders, railings, platforms) Page 21 of 96

177 Etobicoke Creek Facility - Future Risk Precipitation Other Infrastructure Response Considerations Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (eg. Flood level warning) Equipment for facility inspection/maintenance Access to facility On-site access Records Detention Basin Vegetated detention cells Inlet/Outlet structures Concrete spillway Gabian basket retaining structure Diversion Chambers Low flow channel High flow channel Inlet and outlet pipes (150mm mm) Ditches Outlet to storm (600mm) Outlet to sanitary (600mm) Mechanical systems Oil/water seperator Motorized acuators Sampler pump Sluice gates (manual and motorized) HVAC in buildings Potable water line with backflow preventor Ventilation system (exhaust) Electric power supply Electrical panel Lighting Electrical building Control and monitoring systems Gas monitoring system PLCS/SCADA System Fire alarm Level sensor Pump control Flow meter Dialar Alarm Communications Two-way radio Cellular Phone Phone Line (alarms + Phone) Safety systems Chainlink security fence Safety equipment Safety structures (ladders, railings, platforms) Page 22 of 96

178 Etobicoke Creek Facility - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (eg. Flood level warning) Equipment for facility inspection/maintenance Access to facility On-site access Records Detention Basin Vegetated detention cells Inlet/Outlet structures Concrete spillway Gabian basket retaining structure Diversion Chambers Low flow channel High flow channel Inlet and outlet pipes (150mm mm) Ditches Outlet to storm (600mm) Outlet to sanitary (600mm) Mechanical systems Oil/water seperator Motorized acuators Sampler pump Sluice gates (manual and motorized) HVAC in buildings Potable water line with backflow preventor Ventilation system (exhaust) Electric power supply Electrical panel Lighting Electrical building Control and monitoring systems Gas monitoring system PLCS/SCADA System Fire alarm Level sensor Pump control Flow meter Dialar Alarm Communications Two-way radio Cellular Phone Phone Line (alarms + Phone) Safety systems Chainlink security fence Safety equipment Safety structures (ladders, railings, platforms) Page 23 of 96

179 Etobicoke Creek Facility - Existing and Future Risk Compar Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (eg. Flood level warning) Equipment for facility inspection/maintenance Access to facility On-site access Records Detention Basin Vegetated detention cells Inlet/Outlet structures Concrete spillway Gabian basket retaining structure Diversion Chambers Low flow channel High flow channel Inlet and outlet pipes (150mm mm) Ditches Outlet to storm (600mm) Outlet to sanitary (600mm) Mechanical systems Oil/water seperator Motorized acuators Sampler pump Sluice gates (manual and motorized) HVAC in buildings Potable water line with backflow preventor Ventilation system (exhaust) Electric power supply Electrical panel Lighting Electrical building Control and monitoring systems Gas monitoring system PLCS/SCADA System Fire alarm Level sensor Pump control Flow meter Dialar Alarm Communications Two-way radio Cellular Phone Phone Line (alarms + Phone) Safety systems Chainlink security fence Safety equipment Safety structures (ladders, railings, platforms) Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 24 of 96

180 FedEx Pond 16 - Existing Risk Temperature Wind Precipitation Infrastructure Response Considerations High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Riprap Low Flow Channel High Flow Bypass Rip Rap Ditch Inlet structures Outlet structure with Hickenbottom Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 25 of 96

181 FedEx Pond 16 - Existing Risk Precipitation Other Infrastructure Response Considerations Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry storage Pond - vegetated Inlet/Outlet Structures Riprap Low Flow Channel High Flow Bypass Rip Rap Ditch Inlet structures Outlet structure with Hickenbottom Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 26 of 96

182 FedEx Pond 16 - Future Risk Temperature Wind Precipitation Infrastructure Response Considerations High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Riprap Low Flow Channel High Flow Bypass Rip Rap Ditch Inlet structures Outlet structure with Hickenbottom Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 27 of 96

183 FedEx Pond 16 - Future Risk Precipitation Other Infrastructure Response Considerations Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry storage Pond - vegetated Inlet/Outlet Structures Riprap Low Flow Channel High Flow Bypass Rip Rap Ditch Inlet structures Outlet structure with Hickenbottom Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 28 of 96

184 FedEx Pond - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry storage Pond - vegetated Inlet/Outlet Structures Open ditch with gabion Outlet structure with Hickenbottom Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 29 of 96

185 FedEx Pond - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry storage Pond - vegetated Inlet/Outlet Structures Open ditch with gabion Outlet structure with Hickenbottom Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 30 of 96

186 Juliet Pond - Existing Risk Temperature Wind Precipitation Performance Criteria High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Infrastructure Performance Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Health & Safety Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R 2400mm into open ditch mm on east side Outlet Structure Overflow Structure Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 31 of 96

187 Juliet Pond - Existing Risk Precipitation Other Performance Criteria Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Infrastructure Performance Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Health & Safety A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry storage Pond - vegetated Inlet/Outlet Structures 2400mm into open ditch 450mm on east side Outlet Structure Overflow Structure Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 32 of 96

188 Juliet Pond - Future Risk Temperature Wind Precipitation Performance Criteria High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Infrastructure Performance Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Health & Safety Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R 2400mm into open ditch mm on east side Outlet Structure Overflow Structure Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 33 of 96

189 Juliet Pond - Future Risk Precipitation Other Performance Criteria Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Infrastructure Performance Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Health & Safety A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry storage Pond - vegetated Inlet/Outlet Structures 2400mm into open ditch 450mm on east side Outlet Structure Overflow Structure Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 34 of 96

190 Juliet Pond - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry storage Pond - vegetated Inlet/Outlet Structures 2400mm into open ditch mm on east side Outlet Structure Overflow Structure Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 35 of 96

191 Juliet Pond - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry storage Pond - vegetated Inlet/Outlet Structures 2400mm into open ditch 450mm on east side Outlet Structure Overflow Structure Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 36 of 96

192 Moores Facility - Existing Risk Temperature Wind Precipitation Infrastructure Response Considerations High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility On site access Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Reinforced Concrete tank (cells) Dry Surface Storage Pond 1 - vegetated Dry Surface Storage Pond 2 - vegetated Inlet/Outlet structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Inlet mm Inlet mm Inlet Diversion/bypass (including weir plates) Diversion bypass outlet Outlet #1 from separator Bypass Outlet from tank - 600mm Concrete weir - diversion chamber Moores Facility Outfall mm Concrete pipe Sanitary connection via forcemain Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Oil/water separator Building (structure ony) oil/water separator all interior acuators all exterior acuators pumps (sanitary, sample etc) Ventillation System (exhaust + goosenecks) Potable water line - tank Potable water line - separator (backflow valve) Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control/Electrical Building(structure only) Electrical panel Lighting - Electrical Room Lighting - High sodium lights (tank) Backup Power Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Gas Detection System PLC/SCADA System (including Comm Conne) Fire Alarm Level Indicators Facility Alarms (Active 8 System) Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Phone Line (alarms + Phone) Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Page 37 of 96

193 Moores Facility - Existing Risk Precipitation Other Infrastructure Response Considerations Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility On site access Records Detention Basin Reinforced Concrete tank (cells) Dry Surface Storage Pond 1 - vegetated Dry Surface Storage Pond 2 - vegetated Inlet/Outlet structures Inlet mm Inlet mm Inlet 3 Diversion/bypass (including weir plates) Diversion bypass outlet Outlet #1 from separator Bypass Outlet from tank - 600mm Concrete weir - diversion chamber Moores Facility Outfall mm Concrete pipe Sanitary connection via forcemain Mechanical systems Oil/water separator Building (structure ony) oil/water separator all interior acuators all exterior acuators pumps (sanitary, sample etc) Ventillation System (exhaust + goosenecks) Potable water line - tank Potable water line - separator (backflow valve) Electric power supply Control/Electrical Building(structure only) Electrical panel Lighting - Electrical Room Lighting - High sodium lights (tank) Backup Power Control and monitoring systems Gas Detection System PLC/SCADA System (including Comm Conne) Fire Alarm Level Indicators Facility Alarms (Active 8 System) Communications Two-way radio Cellular Phone Phone Line (alarms + Phone) Safety systems Page 38 of 96

194 Moores Facility - Future Risk Temperature Wind Precipitation Infrastructure Response Considerations High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility On site access Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Reinforced Concrete tank (cells) Dry Surface Storage Pond 1 - vegetated Dry Surface Storage Pond 2 - vegetated Inlet/Outlet structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Inlet mm Inlet mm Inlet Diversion/bypass (including weir plates) Diversion bypass outlet Outlet #1 from separator Bypass Outlet from tank - 600mm Concrete weir - diversion chamber Moores Facility Outfall mm Concrete pipe Sanitary connection via forcemain Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Oil/water separator Building (structure ony) oil/water separator all interior acuators all exterior acuators pumps (sanitary, sample etc) Ventillation System (exhaust + goosenecks) Potable water line - tank Potable water line - separator (backflow valve) Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control/Electrical Building(structure only) Electrical panel Lighting - Electrical Room Lighting - High sodium lights (tank) Backup Power Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Gas Detection System PLC/SCADA System (including Comm Conne) Fire Alarm Level Indicators Facility Alarms (Active 8 System) Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Phone Line (alarms + Phone) Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Page 39 of 96

195 Moores Facility - Future Risk Precipitation Other Infrastructure Response Considerations Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility On site access Records Detention Basin Reinforced Concrete tank (cells) Dry Surface Storage Pond 1 - vegetated Dry Surface Storage Pond 2 - vegetated Inlet/Outlet structures Inlet mm Inlet mm Inlet 3 Diversion/bypass (including weir plates) Diversion bypass outlet Outlet #1 from separator Bypass Outlet from tank - 600mm Concrete weir - diversion chamber Moores Facility Outfall mm Concrete pipe Sanitary connection via forcemain Mechanical systems Oil/water separator Building (structure ony) oil/water separator all interior acuators all exterior acuators pumps (sanitary, sample etc) Ventillation System (exhaust + goosenecks) Potable water line - tank Potable water line - separator (backflow valve) Electric power supply Control/Electrical Building(structure only) Electrical panel Lighting - Electrical Room Lighting - High sodium lights (tank) Backup Power Control and monitoring systems Gas Detection System PLC/SCADA System (including Comm Conne) Fire Alarm Level Indicators Facility Alarms (Active 8 System) Communications Two-way radio Cellular Phone Phone Line (alarms + Phone) Safety systems Page 40 of 96

196 Moores Facility - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility On site access Records Detention Basin Reinforced Concrete tank (cells) Dry Surface Storage Pond 1 - vegetated Dry Surface Storage Pond 2 - vegetated Inlet/Outlet structures Inlet mm Inlet mm Inlet Diversion/bypass (including weir plates) Diversion bypass outlet Outlet #1 from separator Bypass Outlet from tank - 600mm Concrete weir - diversion chamber Moores Facility Outfall mm Concrete pipe Sanitary connection via forcemain Mechanical systems Oil/water separator Building (structure ony) oil/water separator all interior acuators all exterior acuators pumps (sanitary, sample etc) Ventillation System (exhaust + goosenecks) Potable water line - tank Potable water line - separator (backflow valve) Electric power supply Control/Electrical Building(structure only) Electrical panel Lighting - Electrical Room Lighting - High sodium lights (tank) Backup Power Control and monitoring systems Gas Detection System PLC/SCADA System (including Comm Conne) Fire Alarm Level Indicators Facility Alarms (Active 8 System) Communications Two-way radio Cellular Phone Phone Line (alarms + Phone) Safety systems Page 41 of 96

197 Moores Facility - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility On site access Records Detention Basin Reinforced Concrete tank (cells) Dry Surface Storage Pond 1 - vegetated Dry Surface Storage Pond 2 - vegetated Inlet/Outlet structures Inlet mm Inlet mm Inlet 3 Diversion/bypass (including weir plates) Diversion bypass outlet Outlet #1 from separator Bypass Outlet from tank - 600mm Concrete weir - diversion chamber Moores Facility Outfall mm Concrete pipe Sanitary connection via forcemain Mechanical systems Oil/water separator Building (structure ony) oil/water separator all interior acuators all exterior acuators pumps (sanitary, sample etc) Ventillation System (exhaust + goosenecks) Potable water line - tank Potable water line - separator (backflow valve) Electric power supply Control/Electrical Building(structure only) Electrical panel Lighting - Electrical Room Lighting - High sodium lights (tank) Backup Power Control and monitoring systems Gas Detection System PLC/SCADA System (including Comm Conne) Fire Alarm Level Indicators Facility Alarms (Active 8 System) Communications Two-way radio Cellular Phone Phone Line (alarms + Phone) Safety systems Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 42 of 96

198 Pond 2 - Existing Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Fencing Highway Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Concrete Pond Concrete Blocks Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R three stormwater inlets Outlet pipe (high and low flow) Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R sluice gate valve for high flow Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Platform - ladder access Page 43 of 96

199 Pond 2 - Existing Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Fencing Highway Records Detention Basin Concrete Pond Concrete Blocks Inlet/Outlet Structures three stormwater inlets Outlet pipe (high and low flow) Mechanical systems sluice gate valve for high flow Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Platform - ladder access Page 44 of 96

200 Pond 2 - Future Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Fencing Highway Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Concrete Pond Concrete Blocks Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R three stormwater inlets Outlet pipe (high and low flow) Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R sluice gate valve for high flow Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Platform - ladder access Page 45 of 96

201 Pond 2 - Future Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Fencing Highway Records Detention Basin Concrete Pond Concrete Blocks Inlet/Outlet Structures three stormwater inlets Outlet pipe (high and low flow) Mechanical systems sluice gate valve for high flow Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Platform - ladder access Page 46 of 96

202 Pond 2 - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Fencing Highway Records Detention Basin Concrete Pond Concrete Blocks Inlet/Outlet Structures three stormwater inlets Outlet pipe (high and low flow) Mechanical systems sluice gate valve for high flow Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Platform - ladder access Page 47 of 96

203 Pond 2 - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Fencing Highway Records Detention Basin Concrete Pond Concrete Blocks Inlet/Outlet Structures three stormwater inlets Outlet pipe (high and low flow) Mechanical systems sluice gate valve for high flow Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Platform - ladder access Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 48 of 96

204 Pond 4 - Existing Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Fencing Highway Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Concrete Pond Concrete Blocks Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R three stormwater inlets Outlet pipe (high and low flow) Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R sluice gate valve for high flow Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Platform - ladder access Page 49 of 96

205 Pond 4 - Existing Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Fencing Highway Records Detention Basin Concrete Pond Concrete Blocks Inlet/Outlet Structures three stormwater inlets Outlet pipe (high and low flow) Mechanical systems sluice gate valve for high flow Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Platform - ladder access Page 50 of 96

206 Pond 4 - Future Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Fencing Highway Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Concrete Pond Concrete Blocks Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R three stormwater inlets Outlet pipe (high and low flow) Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R sluice gate valve for high flow Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Platform - ladder access Page 51 of 96

207 Pond 4 - Future Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Fencing Highway Records Detention Basin Concrete Pond Concrete Blocks Inlet/Outlet Structures three stormwater inlets Outlet pipe (high and low flow) Mechanical systems sluice gate valve for high flow Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Platform - ladder access Page 52 of 96

208 Pond 4 - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Fencing Highway Records Detention Basin Concrete Pond Concrete Blocks Inlet/Outlet Structures three stormwater inlets Outlet pipe (high and low flow) Mechanical systems sluice gate valve for high flow Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Platform - ladder access Page 53 of 96

209 Pond 4 - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Fencing Highway Records Detention Basin Concrete Pond Concrete Blocks Inlet/Outlet Structures three stormwater inlets Outlet pipe (high and low flow) Mechanical systems sluice gate valve for high flow Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Platform - ladder access Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 54 of 96

210 Spring Creek Culvert - Existing Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Access - airside Records Structural System Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Upstream concrete apron Upstream rip-rap Downstream apron Downstream rip-rap Upstream wingwall Cell structures - Original Cell structure Extensions Construction Joint (between cell structures) Cell base (mud slab) Expansion joints Construction joints Baffels Parapet walls culvert inlet Embankment Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Page 55 of 96

211 Spring Creek Culvert - Existing Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Access - airside Records Structural System Upstream concrete apron Upstream rip-rap Downstream apron Downstream rip-rap Upstream wingwall Cell structures - Original Cell structure Extensions Construction Joint (between cell structures) Cell base (mud slab) Expansion joints Construction joints Baffels Parapet walls 1050 culvert inlet Embankment Communications Two-way radio Cellular Phone Page 56 of 96

212 Spring Creek Culvert - Future Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Access - airside Records Structural System Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Upstream concrete apron Upstream rip-rap Downstream apron Downstream rip-rap Upstream wingwall Cell structures - Original Cell structure Extensions Construction Joint (between cell structures) Cell base (mud slab) Expansion joints Construction joints Baffels Parapet walls culvert inlet Embankment Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Page 57 of 96

213 Spring Creek Culvert - Future Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Access - airside Records Structural System Upstream concrete apron Upstream rip-rap Downstream apron Downstream rip-rap Upstream wingwall Cell structures - Original Cell structure Extensions Construction Joint (between cell structures) Cell base (mud slab) Expansion joints Construction joints Baffels Parapet walls 1050 culvert inlet Embankment Communications Two-way radio Cellular Phone Page 58 of 96

214 Spring Creek Culvert - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Access - airside Records Structural System Upstream concrete apron Upstream rip-rap Downstream apron Downstream rip-rap Upstream wingwall Cell structures - Original Cell structure Extensions Construction Joint (between cell structures) Cell base (mud slab) Expansion joints Construction joints Baffels Parapet walls culvert inlet Embankment Communications Two-way radio Cellular Phone Page 59 of 96

215 Spring Creek Culvert - Existing and Future Risk Compariso Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Access to Facility Access On-site Security Access - airside Records Structural System Upstream concrete apron Upstream rip-rap Downstream apron Downstream rip-rap Upstream wingwall Cell structures - Original Cell structure Extensions Construction Joint (between cell structures) Cell base (mud slab) Expansion joints Construction joints Baffels Parapet walls 1050 culvert inlet Embankment Communications Two-way radio Cellular Phone Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 60 of 96

216 SWM Pond 16 - Existing Risk Temperature Wind Precipitation Infrastructure Response Considerations High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Open ditch with gabion Outlet structure with Hickenbottom Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 61 of 96

217 SWM Pond 16 - Existing Risk Precipitation Other Infrastructure Response Considerations Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry storage Pond - vegetated Inlet/Outlet Structures Open ditch with gabion Outlet structure with Hickenbottom Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 62 of 96

218 SWM Pond 16 - Future Risk Temperature Wind Precipitation Infrastructure Response Considerations High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Open ditch with gabion Outlet structure with Hickenbottom Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 63 of 96

219 SWM Pond 16 - Future Risk Precipitation Other Infrastructure Response Considerations Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry storage Pond - vegetated Inlet/Outlet Structures Open ditch with gabion Outlet structure with Hickenbottom Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 64 of 96

220 SWM16 Pond - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry storage Pond - vegetated Inlet/Outlet Structures Open ditch with gabion Outlet structure with Hickenbottom Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 65 of 96

221 SWM16 Pond - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry storage Pond - vegetated Inlet/Outlet Structures Open ditch with gabion Outlet structure with Hickenbottom Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 66 of 96

222 SWM Pond 4 - Existing Risk Temperature Wind Precipitation Infrastructure Response Considerations Diurnal High Temperature Low Temperature Heat Wave Cold Wave Temperature Freeze/Thaw Frost Heavy Fog Variability High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility - berm Access On-site (Berm to Platform) Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Ditch from behind CLS mm inlet mm inlet mm inlet Ditch from groundside snow dump Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R sluice gate valve with turning wheel (900mm) sanitary outlet - valve 375 mm Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Wooden Platform Page 67 of 96

223 SWM Pond 4 - Existing Risk Precipitation Other Infrastructure Response Considerations Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility - berm Access On-site (Berm to Platform) Records Detention Basin Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Ditch from behind CLS 1500 mm inlet 1200 mm inlet 1500 mm inlet Ditch from groundside snow dump Mechanical systems sluice gate valve with turning wheel (900mm) sanitary outlet - valve 375 mm Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Wooden Platform Page 68 of 96

224 SWM Pond 4 - Future Risk Temperature Wind Precipitation Performance Criteria High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility - berm Access On-site (Berm to Platform) Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Ditch from behind CLS mm inlet mm inlet mm inlet Ditch from groundside snow dump Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R sluice gate valve with turning wheel (900mm) sanitary outlet - valve 375mm Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Wooden Platform Page 69 of 96

225 SWM Pond 4 - Future Risk Precipitation Other Performance Criteria Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility - berm Access On-site (Berm to Platform) Records Detention Basin Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Ditch from behind CLS 1500 mm inlet 1200 mm inlet 1500 mm inlet Ditch from groundside snow dump Mechanical systems sluice gate valve with turning wheel (900mm) sanitary outlet - valve 375mm Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Wooden Platform Page 70 of 96

226 SWM4 Pond - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility - berm Access On-site (Berm to Platform) Records Detention Basin Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Ditch from behind CLS mm inlet mm inlet mm inlet Ditch from groundside snow dump Mechanical systems sluice gate valve with turning wheel (900mm) sanitary outlet - valve 375 mm Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Wooden Platform Page 71 of 96

227 SWM4 Pond - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility - berm Access On-site (Berm to Platform) Records Detention Basin Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Ditch from behind CLS 1500 mm inlet 1200 mm inlet 1500 mm inlet Ditch from groundside snow dump Mechanical systems sluice gate valve with turning wheel (900mm) sanitary outlet - valve 375 mm Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Wooden Platform Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 72 of 96

228 SWM Pond 5 - Existing Risk Temperature Wind Precipitation Infrastructure Response Considerations High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road - berm Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R 900 mm Riprap Ditch mm Riprap Ditch mm Riprap Ditch mm CSP (Furthest South) mm CSP (South of 300 mm CP) mm CP (Furthest North) Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 73 of 96

229 SWM Pond 5 - Existing Risk Precipitation Other Infrastructure Response Considerations Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road - berm Records Detention Basin Dry Surface Storage Pond - vegetated Inlet/Outlet Structures 900 mm Riprap Ditch 600 mm Riprap Ditch 600 mm Riprap Ditch 300 mm CSP (Furthest South) 300 mm CSP (South of 300 mm CP) 300 mm CP (Furthest North) Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 74 of 96

230 SWM Pond 5 - Future Risk Temperature Wind Precipitation Infrastructure Response Considerations High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road - berm Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R 900 mm Riprap Ditch mm Riprap Ditch mm Riprap Ditch mm CSP (Furthest South) mm CSP (South of 300 mm CP) mm CP (Furthest North) Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 75 of 96

231 SWM Pond 5 - Future Risk Precipitation Other Infrastructure Response Considerations Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road - berm Records Detention Basin Dry Surface Storage Pond - vegetated Inlet/Outlet Structures 900 mm Riprap Ditch 600 mm Riprap Ditch 600 mm Riprap Ditch 300 mm CSP (Furthest South) 300 mm CSP (South of 300 mm CP) 300 mm CP (Furthest North) Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 76 of 96

232 SWM5 Pond - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road - berm Records Detention Basin Dry Surface Storage Pond - vegetated Inlet/Outlet Structures 900 mm Riprap Ditch mm Riprap Ditch mm Riprap Ditch mm CSP (Furthest South) mm CSP (South of 300 mm CP) mm CP (Furthest North) Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 77 of 96

233 SWM5 Pond - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road - berm Records Detention Basin Dry Surface Storage Pond - vegetated Inlet/Outlet Structures 900 mm Riprap Ditch 600 mm Riprap Ditch 600 mm Riprap Ditch 300 mm CSP (Furthest South) 300 mm CSP (South of 300 mm CP) 300 mm CP (Furthest North) Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 78 of 96

234 SWM Pond 6 - Existing Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road to Facility Access on-site Security Access - airside Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Ditch from 1050 mm approximately 12 o'clock Ditch from 600 mm approximately 1 o'clock Ditch and riprap structure from along Service Road east side Three- Riprap structures from 300 mm roadway drainage on southside of pond Riprap structure from 450 mm roadway drainage on southside of pond Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R sluice gate valve sanitary outlet diversion chamber (not accessible) Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 79 of 96

235 SWM Pond 6 - Existing Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rainon-Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during 9 or more days with January, February and freezing rain in one year March Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road to Facility Access on-site Security Access - airside Records Detention Basin Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Ditch from 1050 mm approximately 12 o'clock Ditch from 600 mm approximately 1 o'clock Ditch and riprap structure from along Service Road east side Three- Riprap structures from 300 mm roadway drainage on southside of pond Riprap structure from 450 mm roadway drainage on southside of pond Mechanical systems sluice gate valve sanitary outlet diversion chamber (not accessible) Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 80 of 96

236 SWM Pond 6 - Future Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road to Facility Access on-site Security Access - airside Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Ditch from 1050 mm approximately 12 o'clock Ditch from 600 mm approximately 1 o'clock Ditch and riprap structure from along Service Road east side Three- Riprap structures from 300 mm roadway drainage on southside of pond Riprap structure from 450 mm roadway drainage on southside of pond Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R sluice gate valve sanitary outlet diversion chamber (not accessible) Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 81 of 96

237 SWM Pond 6 - Future Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rainon-Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during 9 or more days with January, February and freezing rain in one year March Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road to Facility Access on-site Security Access - airside Records Detention Basin Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Ditch from 1050 mm approximately 12 o'clock Ditch from 600 mm approximately 1 o'clock Ditch and riprap structure from along Service Road east side Three- Riprap structures from 300 mm roadway drainage on southside of pond Riprap structure from 450 mm roadway drainage on southside of pond Mechanical systems sluice gate valve sanitary outlet diversion chamber (not accessible) Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 82 of 96

238 SWM6 Pond - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road to Facility Access on-site Security Access - airside Records Detention Basin Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Ditch from 1050 mm approximately 12 o'clock Ditch from 600 mm approximately 1 o'clock Ditch and riprap structure from along Service Road east side Three- Riprap structures from 300 mm roadway drainage on so Riprap structure from 450 mm roadway drainage on southside o Mechanical systems sluice gate valve sanitary outlet diversion chamber (not accessible) Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 83 of 96

239 SWM6 Pond - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road to Facility Access on-site Security Access - airside Records Detention Basin Dry Surface Storage Pond - vegetated Inlet/Outlet Structures Ditch from 1050 mm approximately 12 o'clock Ditch from 600 mm approximately 1 o'clock Ditch and riprap structure from along Service Road east side Three- Riprap structures from 300 mm roadway drainage on so Riprap structure from 450 mm roadway drainage on southside o Mechanical systems sluice gate valve sanitary outlet diversion chamber (not accessible) Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Heavy 5 day total Snow Storm/ Snow Winter Rain/Rain- Rainfall on-snow Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Hurricane / Drought/Dry Page 84 of 96

240 SWM A14 Pond - Existing Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Maintenance/Inspection) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road Access on-site Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry Surface Storage Pond - vegetated Spillway structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R open ditch on West Side mm on west side from airside Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 85 of 96

241 SWM A14 Pond - Existing Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Maintenance/Inspection) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road Access on-site Records Detention Basin Dry Surface Storage Pond - vegetated Spillway structures open ditch on West Side 1500mm on west side from airside Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 86 of 96

242 SWM A14 Pond - Future Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Maintenance/Inspection) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road Access on-site Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry Surface Storage Pond - vegetated Spillway structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R open ditch on West Side mm on west side from airside Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 87 of 96

243 SWM A14 Pond - Future Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Maintenance/Inspection) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road Access on-site Records Detention Basin Dry Surface Storage Pond - vegetated Spillway structures open ditch on West Side 1500mm on west side from airside Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 88 of 96

244 SWMA14 Pond - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Maintenance/Inspection) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road Access on-site Records Detention Basin Dry Surface Storage Pond - vegetated Spillway structures open ditch on West Side mm on west side from airside Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 89 of 96

245 SWMA14 Pond - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Maintenance/Inspection) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access road Access on-site Records Detention Basin Dry Surface Storage Pond - vegetated Spillway structures open ditch on West Side 1500mm on west side from airside Mechanical systems Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 90 of 96

246 WM4A Pond - Existing Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry Surface storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Open ditch from Derry Road Open ditch from GAA mm sanitary sewer connection Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R sluice gate valve via T-bar key sanitary outlet - valve 300mm Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 91 of 96

247 WM4A Pond - Existing Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry Surface storage Pond - vegetated Inlet/Outlet Structures Open ditch from Derry Road Open ditch from GAA 300mm sanitary sewer connection Mechanical systems sluice gate valve via T-bar key sanitary outlet - valve 300mm Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 92 of 96

248 WM4A Pond - Future Risk Temperature Wind Precipitation Infrastructure Response Consideration High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects Day(s) with a max. temp exceeding 35 C Day(s) with a min. temp below -30 C Three or more consecutive days >32 C Three or more consecutive days with min temp. <-20 C and max temp. < - 10 C Daily temp. variation of more than 25 C 85 or more freeze-thaw cycles within one year 175 or more frost days within one year 15 or more hours with visibility <0km within one year 8 or more days with max. winds of >=63km/hr in one year Vortex extending upward from the earth's surface at least as far as cloud base (occuring near site) Days with rainfall > 125mm Days with rainfall > 50mm 23 or more days of >10mm of rain within one year Administration / Operation Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Dry Surface storage Pond - vegetated Inlet/Outlet Structures Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Open ditch from Derry Road Open ditch from GAA mm sanitary sewer connection Mechanical systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R sluice gate valve via T-bar key sanitary outlet - valve 300mm Electric power supply Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Control and monitoring systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Communications Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Two-way radio Cellular Phone Safety systems Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Berm Page 93 of 96

249 WM4A Pond - Future Risk Precipitation Other Infrastructure Response Consideration Heavy 5 day total Rainfall Winter Rain/Rain-on- Snow Freezing Rain Ice Storm Snow Storm/ Blizzard Heavy Snowfall Snow Accumulation Hailstorm Acid Rain Wet Days Lightning Hurricane / Tropical Storms Drought/Dry Periods Dust Storm Infrastructure Component Structural Design Infrastructure Functionality Serviceability Watershed, SW, and GW Operations & Maintenance Emergency Response Insurance Considerations Policy Considerations Social Effects Environmental Effects A five day period receiving > 100mm of rainfall Greater than 25mm of rain falling during January, February and March 9 or more days with freezing rain in one year Severe Freezing Rain events 8 or more days with blowing snow in one year Days with snowfall >10cm 5 or more consecuritve days with a snow depth of >30cm Days with precipitation falling as ice particles (dia. > 5mm) Precipitation with ph of <4 112 or more days with measureable rainfall >0.2mm in one year lightning strikes on the airport property within one year Cyclones of a tropical origin with sustained surface wind speeds >63km/hr 10 consecutive days with <0.2mm of precipitation Visibility <1km for more than an hour Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry Surface storage Pond - vegetated Inlet/Outlet Structures Open ditch from Derry Road Open ditch from GAA 300mm sanitary sewer connection Mechanical systems sluice gate valve via T-bar key sanitary outlet - valve 300mm Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 94 of 96

250 WM4A Pond - Existing and Future Risk Comparison Infrastructure Component High Temperature Low Temperature Heat Wave Cold Wave Diurnal Temperature Variability Freeze/Thaw Frost Heavy Fog High Wind/ Downburst Tornado Extreme Heavy Rainfall Heavy Rainfall Rain (Frequency) Administration / Operation Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry Surface storage Pond - vegetated Inlet/Outlet Structures Open ditch from Derry Road Open ditch from GAA mm sanitary sewer connection Mechanical systems sluice gate valve via T-bar key sanitary outlet - valve 300mm Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Page 95 of 96

251 WM4A Pond - Existing and Future Risk Comparison Infrastructure Component Administration / Operation Personnel (Maintenance/Inspection) Procedures (Inspections/Maintenance) Emergency Procedures (Flood Level Warning) Equipment for Facility Inspection/Maintenance Access to Facility Access On-site Security Access - airside Records Detention Basin Dry Surface storage Pond - vegetated Inlet/Outlet Structures Open ditch from Derry Road Open ditch from GAA 300mm sanitary sewer connection Mechanical systems sluice gate valve via T-bar key sanitary outlet - valve 300mm Electric power supply Control and monitoring systems Communications Two-way radio Cellular Phone Safety systems Berm Heavy 5 day total Winter Rain/Rainon-Snow Snow Storm/ Snow Hurricane / Drought/Dry Rainfall Freezing Rain Ice Storm Blizzard Heavy Snowfall Accumulation Hailstorm Acid Rain Wet Days Lightning Tropical Storms Periods Dust Storm Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch. Ex. Fu. Ch Page 96 of 96

252 Toronto Pearson Infrastructure Vulnerability Assessment Appendix C Ranked Risk Tables

253 LIST OF TABLES Table 1 Pond 6B...2 Table 2 Aeroquay...4 Table 3 Carlingview Facility...8 Table 4 Etobicoke Creek Facility...13 Table 5 Juliet Pond...18 Table 6 Moores Facility...21 Table 7 Pond Table 8 Pond Table 9 SWM4 Pond...32 Table 10 SWM5 Pond...35 Table 11 SWM6 Pond...37 Table 12 SWM16 Pond...40 Table 13 SWMA14 Pond...42 Table 14 WM4A Pond...44 Table 15 Spring Creek Culvert...47 Table 16 FedEx Facility

254 Table 1 Pond 6B Infrastructure Climate Parameter Existing Risk Future Risk Personnel (Maintenance/Inspection) Hailstorm Vegetated Pond Heavy Rainfall Access to Facility Snow Accumulation Access On-site Snow Accumulation Vegetated Pond Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall Access to Facility Heavy Snowfall Access On-site Heavy Snowfall Vegetated Pond Heavy Snowfall Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access to Facility Heavy Rainfall Access On-site Heavy Rainfall Berm Heavy Rainfall Stormwater inlets Heavy Rainfall Outlet pipe Heavy Rainfall Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation Equipment for Facility Inspection/Maintenance Snow Accumulation Stormwater inlets Snow Accumulation Outlet pipe Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Vegetated Pond Winter Rain/Rain-on-Snow Two-way radio Lightning Cellular Phone Lightning Personnel (Maintenance/Inspection) Freezing Rain Procedures (Inspections/Maintenance) Freezing Rain Access to Facility Freezing Rain Access On-site Freezing Rain Highway Freezing Rain Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Equipment for Facility Inspection/Maintenance Heavy Rainfall Access to Facility Rain (Frequency) Access On-site Rain (Frequency) Highway Heavy Rainfall Stormwater inlets Rain (Frequency) Outlet pipe Rain (Frequency)

255 Vegetated Pond Heavy 5 day total Rainfall Stormwater inlets Heavy 5 day total Rainfall Outlet pipe Heavy 5 day total Rainfall Two-way radio Ice Storm Cellular Phone Ice Storm Procedures (Inspections/Maintenance) Winter Rain/Rain-on-Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Heavy Snowfall Equipment for Facility Inspection/Maintenance Heavy Snowfall Access to Facility Snow Storm/ Blizzard Access On-site High Wind/ Downburst Access On-site Winter Rain/Rain-on-Snow Access On-site Snow Storm/ Blizzard Highway Heavy Snowfall Two-way radio High Wind/ Downburst Cellular Phone High Wind/ Downburst Vegetated Pond Drought/Dry Periods Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Heavy 5 day total Rainfall 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Heavy 5 day total Rainfall 8 12 Emergency Procedures (Flood Level Warning) Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Low Temperature 12 8 Equipment for Facility Inspection/Maintenance Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Ice Storm 8 12 Access to Facility Ice Storm 8 12 Access On-site Heavy 5 day total Rainfall 8 12 Access On-site Ice Storm 8 12 Highway Ice Storm 8 12 Vegetated Pond Freezing Rain 8 12 Vegetated Pond Ice Storm 8 12 Two-way radio Freezing Rain 8 12 Cellular Phone Freezing Rain 8 12 Personnel (Maintenance/Inspection) Hurricane / Tropical 6 12 Storms Access to Facility Freeze/Thaw 12 6 Access On-site Freeze/Thaw 12 6 Highway Freeze/Thaw 12 6 Stormwater inlets Extreme Heavy Rainfall 6 12 Outlet pipe Extreme Heavy Rainfall

256 Table 2 Aeroquay Infrastructure Climate Parameter Existing Risk Future Risk Personnel (Maintenance/Inspection) Hailstorm Inlet mm Heavy Rainfall Outlet #1 from separator - 300mm Heavy Rainfall Bypass Outlet from tank - 600mm Heavy Rainfall Concrete weir - Diversion Chamber Heavy Rainfall Aeroquay Outfall mm fibreglass pipe Heavy Rainfall Access to Facility Snow Accumulation Access On-site Snow Accumulation On site access to Outfall Snow Accumulation Reinforced Concrete tank (irrigation tank) Snow Accumulation Inlet mm Snow Accumulation Outlet #1 from separator - 300mm Snow Accumulation Bypass Outlet from tank - 600mm Snow Accumulation Concrete weir - Diversion Chamber Snow Accumulation Aeroquay Outfall mm fibreglass pipe Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall Access On-site Heavy Snowfall On site access to Outfall Heavy Snowfall Reinforced Concrete tank (irrigation tank) Heavy Snowfall sluice gate acuator into separator Heavy Snowfall sluice gate acuator into irrigation tank Heavy Snowfall sluice gate acuator - bypass Heavy Snowfall Hardwire Phone Heavy Snowfall Two-way radio Heavy Snowfall Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access to Facility Heavy Rainfall Access On-site Heavy Rainfall On site access to Outfall Heavy Rainfall Reinforced Concrete tank (irrigation tank) Heavy Rainfall Reinforced Concrete tank (irrigation tank) Rain (Frequency) Inlet mm Rain (Frequency) Outlet #1 from separator - 300mm Rain (Frequency) Bypass Outlet from tank - 600mm Rain (Frequency) Concrete weir - Diversion Chamber Rain (Frequency) Aeroquay Outfall mm fibreglass pipe Rain (Frequency) Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation sluice gate acuator into separator Snow Accumulation sluice gate acuator into irrigation tank Snow Accumulation

257 sluice gate acuator - bypass Snow Accumulation Hardwire Phone Snow Accumulation Two-way radio Snow Accumulation Reinforced Concrete tank (irrigation tank) Winter Rain/Rain-on-Snow Inlet mm Winter Rain/Rain-on-Snow Outlet #1 from separator - 300mm Winter Rain/Rain-on-Snow Bypass Outlet from tank - 600mm Winter Rain/Rain-on-Snow Concrete weir - Diversion Chamber Winter Rain/Rain-on-Snow Aeroquay Outfall mm fibreglass pipe Winter Rain/Rain-on-Snow Personnel (Maintenance/Inspection) Freezing Rain Procedures (Inspections/Maintenance) Freezing Rain Access to Facility Freezing Rain Access On-site Freezing Rain On site access to Outfall Freezing Rain Inlet mm Heavy 5 day total Rainfall Inlet mm Freezing Rain Outlet #1 from separator - 300mm Heavy 5 day total Rainfall Outlet #1 from separator - 300mm Freezing Rain Bypass Outlet from tank - 600mm Heavy 5 day total Rainfall Bypass Outlet from tank - 600mm Freezing Rain Concrete weir - Diversion Chamber Heavy 5 day total Rainfall Concrete weir - Diversion Chamber Freezing Rain Aeroquay Outfall mm fibreglass pipe Heavy 5 day total Rainfall Aeroquay Outfall mm fibreglass pipe Freezing Rain oil/water separator Cold Wave oil/water separator Ice Storm sluice gate acuator into separator Cold Wave sluice gate acuator into irrigation tank Cold Wave sluice gate acuator - bypass Cold Wave Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Access On-site Rain (Frequency) On site access to Outfall Rain (Frequency) Electrical Panel High Temperature Electrical Panel Heat Wave oil/water separator Low Temperature sluice gate acuator into separator Low Temperature sluice gate acuator into irrigation tank Low Temperature sluice gate acuator - bypass Low Temperature Procedures (Inspections/Maintenance) Winter Rain/Rain-on-Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Winter Rain/Rain-on-Snow Emergency Procedures (Flood Level Warning) Heavy Snowfall Access to Facility Snow Storm/ Blizzard Access to Facility Heavy Snowfall Access On-site High Wind/ Downburst Access On-site Winter Rain/Rain-on-Snow

258 Access On-site Snow Storm/ Blizzard On site access to Outfall High Wind/ Downburst On site access to Outfall Winter Rain/Rain-on-Snow On site access to Outfall Snow Storm/ Blizzard Inlet mm Heavy Snowfall Outlet #1 from separator - 300mm Heavy Snowfall Bypass Outlet from tank - 600mm Heavy Snowfall Concrete weir - Diversion Chamber Heavy Snowfall Aeroquay Outfall mm fibreglass pipe Heavy Snowfall sluice gate acuator into separator Snow Storm/ Blizzard sluice gate acuator into irrigation tank Snow Storm/ Blizzard sluice gate acuator - bypass Snow Storm/ Blizzard Electrical Panel Lightning Hardwire Phone High Wind/ Downburst Hardwire Phone Lightning Two-way radio High Wind/ Downburst Two-way radio Lightning Mechanical Room Snow Accumulation Control Room - structure only Snow Accumulation oil/water separator Snow Accumulation Gas Detection System Snow Accumulation PLC/SCADA System Snow Accumulation Fire Alarm Snow Accumulation Level Indicators Snow Accumulation Cellular Phone Snow Accumulation Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Heavy 5 day total Rainfall 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Heavy 5 day total Rainfall 8 12 Emergency Procedures (Flood Level Warning) Freezing Rain 8 12 Access to Facility Ice Storm 8 12 Access On-site Heavy 5 day total Rainfall 8 12 Access On-site Ice Storm 8 12 On site access to Outfall Heavy 5 day total Rainfall 8 12 On site access to Outfall Ice Storm 8 12 Reinforced Concrete tank (irrigation tank) Heavy 5 day total Rainfall 8 12 oil/water separator Freezing Rain 8 12 sluice gate acuator into separator Freezing Rain 8 12 sluice gate acuator into irrigation tank Freezing Rain 8 12 sluice gate acuator - bypass Freezing Rain 8 12 Hardwire Phone Ice Storm 8 12 Two-way radio Ice Storm 8 12 Personnel (Maintenance/Inspection) Hurricane / Tropical 6 12 Storms Access to Facility Freeze/Thaw 12 6 Access On-site Freeze/Thaw 12 6 On site access to Outfall Freeze/Thaw 12 6 Inlet mm Extreme Heavy Rainfall

259 Outlet #1 from separator - 300mm Extreme Heavy Rainfall 6 12 Bypass Outlet from tank - 600mm Extreme Heavy Rainfall 6 12 Concrete weir - Diversion Chamber Extreme Heavy Rainfall 6 12 Aeroquay Outfall mm fibreglass pipe Extreme Heavy Rainfall

260 Table 3 Carlingview Facility Infrastructure Climate Parameter Existing Risk Future Risk Personnel (Maintenance/Inspection) Hailstorm Access to Facility Snow Accumulation On site access (including hatches) Snow Accumulation Gate Access (security key or ticket machine) Snow Accumulation Leased Parking Lot Snow Accumulation Reinforced Concrete Tanks (1 & 2) Snow Accumulation Diversion Vaults (1 & 2) Snow Accumulation Bypass inlet mm Snow Accumulation Bypass outlet #1 to tank mm Snow Accumulation Bypass Outlet #2 to storm mm Snow Accumulation Inlet from tank mm Snow Accumulation Weir plates Snow Accumulation Concrete weirs Snow Accumulation Low flow channel Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall On site access (including hatches) Heavy Snowfall Gate Access (security key or ticket machine) Heavy Snowfall Leased Parking Lot Heavy Snowfall Reinforced Concrete Tanks (1 & 2) Heavy Snowfall Ventillation System (exhaust + goosenecks) Heavy Snowfall All electronic controled actuators Heavy Snowfall All manual actuators Heavy Snowfall Sluice gate w/ electronic control acuator Heavy Snowfall Sluice gate - manual Heavy Snowfall Potable water lines (tank, separator) Heavy Snowfall Two-way radio Heavy Snowfall Cellular Phone Heavy Snowfall Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access to Facility Heavy Rainfall On site access (including hatches) Heavy Rainfall Gate Access (security key or ticket machine) Heavy Rainfall Leased Parking Lot Heavy Rainfall Reinforced Concrete Tanks (1 & 2) Heavy Rainfall Reinforced Concrete Tanks (1 & 2) Rain (Frequency) Diversion Vaults (1 & 2) Rain (Frequency) Bypass inlet mm Rain (Frequency) Bypass outlet #1 to tank mm Rain (Frequency) Bypass Outlet #2 to storm mm Rain (Frequency) Inlet from tank mm Rain (Frequency) Weir plates Rain (Frequency)

261 Concrete weirs Rain (Frequency) Low flow channel Rain (Frequency) Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation Equipment for Facility Inspection/Maintenance Snow Accumulation Ventillation System (exhaust + goosenecks) Snow Accumulation All electronic controled actuators Snow Accumulation All manual actuators Snow Accumulation Sluice gate w/ electronic control acuator Snow Accumulation Sluice gate - manual Snow Accumulation Potable water lines (tank, separator) Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Reinforced Concrete Tanks (1 & 2) Winter Rain/Rain-on Snow Diversion Vaults (1 & 2) Winter Rain/Rain-on Snow Bypass inlet mm Winter Rain/Rain-on Snow Bypass outlet #1 to tank mm Winter Rain/Rain-on Snow Bypass Outlet #2 to storm mm Winter Rain/Rain-on Snow Inlet from tank mm Winter Rain/Rain-on Snow Weir plates Winter Rain/Rain-on Snow Concrete weirs Winter Rain/Rain-on Snow Low flow channel Winter Rain/Rain-on Snow Personnel (Maintenance/Inspection) Freezing Rain Procedures (Inspections/Maintenance) Freezing Rain Access to Facility Freezing Rain On site access (including hatches) Freezing Rain Gate Access (security key or ticket machine) Freezing Rain Leased Parking Lot Freezing Rain Diversion Vaults (1 & 2) Heavy 5 day total Rainfall Diversion Vaults (1 & 2) Freezing Rain Bypass inlet mm Heavy 5 day total Rainfall Bypass inlet mm Freezing Rain Bypass outlet #1 to tank mm Heavy 5 day total Rainfall Bypass outlet #1 to tank mm Freezing Rain Bypass Outlet #2 to storm mm Heavy 5 day total Rainfall Bypass Outlet #2 to storm mm Freezing Rain Inlet from tank mm Heavy 5 day total

262 Rainfall Inlet from tank mm Freezing Rain Weir plates Heavy 5 day total Rainfall Weir plates Freezing Rain Concrete weirs Heavy 5 day total Rainfall Concrete weirs Freezing Rain Low flow channel Heavy 5 day total Rainfall Low flow channel Freezing Rain Ventillation System (exhaust + goosenecks) Cold Wave Oil/water separator Cold Wave Oil/water separator Ice Storm All electronic controled actuators Cold Wave All manual actuators Cold Wave Sluice gate w/ electronic control acuator Cold Wave Sluice gate - manual Cold Wave Potable water lines (tank, separator) Cold Wave Interior safety structures Freezing Rain (railings/staircases/ladders) Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Equipment for Facility Inspection/Maintenance Heavy Rainfall On site access (including hatches) Rain (Frequency) Gate Access (security key or ticket machine) Rain (Frequency) Diversion Vaults (1 & 2) Heavy Rainfall Bypass inlet mm Heavy Rainfall Bypass outlet #1 to tank mm Heavy Rainfall Bypass Outlet #2 to storm mm Heavy Rainfall Inlet from tank mm Heavy Rainfall Weir plates Heavy Rainfall Concrete weirs Heavy Rainfall Low flow channel Heavy Rainfall Oil/water separator concrete block building Wet Days Concrete block electrical building Wet Days Electrical Distribution Panel High Temperature Electrical Distribution Panel Heat Wave Oil/water separator Low Temperature All electronic controled actuators Low Temperature All manual actuators Low Temperature Sluice gate w/ electronic control acuator Low Temperature Sluice gate - manual Low Temperature Potable water lines (tank, separator) Low Temperature Procedures (Inspections/Maintenance) Winter Rain/Rain-on Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Winter Rain/Rain-on

263 Snow Emergency Procedures (Flood Level Warning) Heavy Snowfall Equipment for Facility Inspection/Maintenance Heavy Snowfall Access to Facility Snow Storm/ Blizzard Access to Facility Heavy Snowfall On site access (including hatches) High Wind/ Downburst On site access (including hatches) Winter Rain/Rain-on Snow On site access (including hatches) Snow Storm/ Blizzard Gate Access (security key or ticket machine) High Wind/ Downburst Gate Access (security key or ticket machine) Winter Rain/Rain-on Snow Gate Access (security key or ticket machine) Snow Storm/ Blizzard Leased Parking Lot Snow Storm/ Blizzard Diversion Vaults (1 & 2) Heavy Snowfall Bypass inlet mm Heavy Snowfall Bypass outlet #1 to tank mm Heavy Snowfall Bypass Outlet #2 to storm mm Heavy Snowfall Inlet from tank mm Heavy Snowfall Weir plates Heavy Snowfall Concrete weirs Heavy Snowfall Low flow channel Heavy Snowfall Ventillation System (exhaust + goosenecks) Snow Storm/ Blizzard All electronic controled actuators Snow Storm/ Blizzard All manual actuators Snow Storm/ Blizzard Sluice gate w/ electronic control acuator Snow Storm/ Blizzard Sluice gate - manual Snow Storm/ Blizzard Potable water lines (tank, separator) Snow Storm/ Blizzard Electrical Distribution Panel Lightning Two-way radio High Wind/ Downburst Two-way radio Lightning Cellular Phone High Wind/ Downburst Cellular Phone Lightning Interior safety structures Heavy Snowfall (railings/staircases/ladders) Oil/water separator concrete block building Snow Accumulation Oil/water separator Snow Accumulation Concrete block electrical building Snow Accumulation Gas Detection System Snow Accumulation PLCS/SCADA System Snow Accumulation Fire Alarm Snow Accumulation Level Indicators Snow Accumulation Flow Meters Snow Accumulation Pump controls(sample & sump) Snow Accumulation Phone Line (alarms + phone) Snow Accumulation Interior safety structures Snow Accumulation (railings/staircases/ladders) Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Heavy 5 day total

264 Rainfall Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Heavy 5 day total 8 12 Rainfall Emergency Procedures (Flood Level Warning) Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Low Temperature 12 8 Equipment for Facility Inspection/Maintenance Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Ice Storm 8 12 Access to Facility Ice Storm 8 12 On site access (including hatches) Heavy 5 day total 8 12 Rainfall On site access (including hatches) Ice Storm 8 12 Gate Access (security key or ticket machine) Heavy 5 day total 8 12 Rainfall Gate Access (security key or ticket machine) Ice Storm 8 12 Leased Parking Lot Ice Storm 8 12 Reinforced Concrete Tanks (1 & 2) Heavy 5 day total 8 12 Rainfall Ventillation System (exhaust + goosenecks) Low Temperature 12 8 Ventillation System (exhaust + goosenecks) Freezing Rain 8 12 Oil/water separator Freezing Rain 8 12 All electronic controled actuators Freezing Rain 8 12 All manual actuators Freezing Rain 8 12 Sluice gate w/ electronic control acuator Freezing Rain 8 12 Sluice gate - manual Freezing Rain 8 12 Potable water lines (tank, separator) Freezing Rain 8 12 Two-way radio Ice Storm 8 12 Cellular Phone Ice Storm 8 12 Interior safety structures Ice Storm 8 12 (railings/staircases/ladders) Personnel (Maintenance/Inspection) Hurricane / Tropical 6 12 Storms Access to Facility Freeze/Thaw 12 6 On site access (including hatches) Freeze/Thaw 12 6 Gate Access (security key or ticket machine) Freeze/Thaw 12 6 Diversion Vaults (1 & 2) Extreme Heavy Rainfall 6 12 Bypass inlet mm Extreme Heavy Rainfall 6 12 Bypass outlet #1 to tank mm Extreme Heavy Rainfall 6 12 Bypass Outlet #2 to storm mm Extreme Heavy Rainfall 6 12 Inlet from tank mm Extreme Heavy Rainfall 6 12 Weir plates Extreme Heavy Rainfall 6 12 Concrete weirs Extreme Heavy Rainfall 6 12 Low flow channel Extreme Heavy Rainfall

265 Table 4 Etobicoke Creek Facility Infrastructure Climate Parameter Existing Risk Future Risk Personnel (Maintenance/Inspection) Hailstorm Vegetated detention cells Heavy Rainfall Access to facility Snow Accumulation On-site access Snow Accumulation Vegetated detention cells Snow Accumulation Concrete spillway Snow Accumulation Gabian basket retaining structure Snow Accumulation Diversion Chambers Snow Accumulation Low flow channel Snow Accumulation High flow channel Snow Accumulation Inlet and outlet pipes (150mm mm) Snow Accumulation Ditches Snow Accumulation Outlet to storm (600mm) Snow Accumulation Outlet to sanitary (600mm) Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall On-site access Heavy Snowfall Vegetated detention cells Heavy Snowfall Motorized acuators Heavy Snowfall Sampler pump Heavy Snowfall Sluice gates (manual and motorized) Heavy Snowfall HVAC in buildings Heavy Snowfall Potable water line with backflow preventor Heavy Snowfall Ventilation system (exhaust) Heavy Snowfall Two-way radio Heavy Snowfall Cellular Phone Heavy Snowfall Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (eg. Flood level Rain (Frequency) warning) Access to facility Heavy Rainfall On-site access Heavy Rainfall Vegetated detention cells Rain (Frequency) Concrete spillway Rain (Frequency) Gabian basket retaining structure Rain (Frequency) Diversion Chambers Rain (Frequency) Low flow channel Rain (Frequency) High flow channel Rain (Frequency) Inlet and outlet pipes (150mm mm) Rain (Frequency) Ditches Heavy Rainfall Outlet to storm (600mm) Rain (Frequency) Outlet to sanitary (600mm) Rain (Frequency) Personnel (Maintenance/Inspection) Snow Accumulation

266 Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (eg. Flood level Snow Accumulation warning) Equipment for facility inspection/maintenance Snow Accumulation Motorized acuators Snow Accumulation Sampler pump Snow Accumulation Sluice gates (manual and motorized) Snow Accumulation HVAC in buildings Snow Accumulation Potable water line with backflow preventor Snow Accumulation Ventilation system (exhaust) Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Vegetated detention cells Winter Rain/Rain-on Snow Concrete spillway Winter Rain/Rain-on Snow Gabian basket retaining structure Winter Rain/Rain-on Snow Diversion Chambers Winter Rain/Rain-on Snow Low flow channel Winter Rain/Rain-on Snow High flow channel Winter Rain/Rain-on Snow Inlet and outlet pipes (150mm mm) Winter Rain/Rain-on Snow Outlet to storm (600mm) Winter Rain/Rain-on Snow Outlet to sanitary (600mm) Winter Rain/Rain-on Snow Personnel (Maintenance/Inspection) Freezing Rain Procedures (Inspections/Maintenance) Freezing Rain Access to facility Freezing Rain On-site access Freezing Rain Concrete spillway Heavy 5 day total Rainfall Concrete spillway Freezing Rain Gabian basket retaining structure Heavy 5 day total Rainfall Gabian basket retaining structure Freezing Rain Diversion Chambers Heavy 5 day total Rainfall Diversion Chambers Freezing Rain Low flow channel Heavy 5 day total Rainfall Low flow channel Freezing Rain High flow channel Heavy 5 day total Rainfall High flow channel Freezing Rain Inlet and outlet pipes (150mm mm) Heavy 5 day total Rainfall Inlet and outlet pipes (150mm mm) Freezing Rain Outlet to storm (600mm) Heavy 5 day total Rainfall Outlet to storm (600mm) Freezing Rain Outlet to sanitary (600mm) Heavy 5 day total Rainfall Outlet to sanitary (600mm) Freezing Rain Oil/water seperator Cold Wave

267 Oil/water seperator Ice Storm Motorized acuators Cold Wave Sampler pump Cold Wave Sluice gates (manual and motorized) Cold Wave HVAC in buildings Cold Wave Potable water line with backflow preventor Cold Wave Ventilation system (exhaust) Cold Wave Safety structures (ladders, railings, platforms) Freezing Rain Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (eg. Flood level Heavy Rainfall warning) Equipment for facility inspection/maintenance Heavy Rainfall On-site access Rain (Frequency) Concrete spillway Heavy Rainfall Gabian basket retaining structure Heavy Rainfall Diversion Chambers Heavy Rainfall Low flow channel Heavy Rainfall High flow channel Heavy Rainfall Inlet and outlet pipes (150mm mm) Heavy Rainfall Ditches Rain (Frequency) Outlet to storm (600mm) Heavy Rainfall Outlet to sanitary (600mm) Heavy Rainfall Electrical panel High Temperature Electrical panel Heat Wave Electrical building Wet Days Vegetated detention cells Heavy 5 day total Rainfall Ditches Heavy 5 day total Rainfall Oil/water seperator Low Temperature Motorized acuators Low Temperature Sampler pump Low Temperature Sluice gates (manual and motorized) Low Temperature Potable water line with backflow preventor Low Temperature Procedures (Inspections/Maintenance) Winter Rain/Rain-on Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (eg. Flood level Winter Rain/Rain-on warning) Snow Emergency Procedures (eg. Flood level Heavy Snowfall warning) Equipment for facility inspection/maintenance Heavy Snowfall Access to facility Snow Storm/ Blizzard Access to facility Heavy Snowfall On-site access High Wind/ Downburst On-site access Winter Rain/Rain-on Snow On-site access Snow Storm/ Blizzard Concrete spillway Heavy Snowfall Gabian basket retaining structure Heavy Snowfall

268 Diversion Chambers Heavy Snowfall Low flow channel Heavy Snowfall High flow channel Heavy Snowfall Inlet and outlet pipes (150mm mm) Heavy Snowfall Ditches Winter Rain/Rain-on Snow Outlet to storm (600mm) Heavy Snowfall Outlet to sanitary (600mm) Heavy Snowfall Motorized acuators Snow Storm/ Blizzard Sampler pump Snow Storm/ Blizzard Sluice gates (manual and motorized) Snow Storm/ Blizzard HVAC in buildings Snow Storm/ Blizzard Potable water line with backflow preventor Snow Storm/ Blizzard Ventilation system (exhaust) Snow Storm/ Blizzard Electrical panel Lightning Two-way radio High Wind/ Downburst Two-way radio Lightning Cellular Phone High Wind/ Downburst Cellular Phone Lightning Safety structures (ladders, railings, platforms) Heavy Snowfall Procedures (Inspections/Maintenance) Drought/Dry Periods Vegetated detention cells Drought/Dry Periods Oil/water seperator Snow Accumulation Electrical building Snow Accumulation Gas monitoring system Snow Accumulation PLCS/SCADA System Snow Accumulation Fire alarm Snow Accumulation Level sensor Snow Accumulation Pump control Snow Accumulation Flow meter Snow Accumulation Dialar Alarm Snow Accumulation Phone Line (alarms + Phone) Snow Accumulation Safety structures (ladders, railings, platforms) Snow Accumulation Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Heavy 5 day total Rainfall 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (eg. Flood level Heavy 5 day total Rainfall 8 12 warning) Emergency Procedures (eg. Flood level Freezing Rain 8 12 warning) Equipment for facility inspection/maintenance Low Temperature 12 8 Equipment for facility inspection/maintenance Freezing Rain 8 12 Equipment for facility inspection/maintenance Ice Storm 8 12 Access to facility Ice Storm 8 12 On-site access Heavy 5 day total Rainfall 8 12 On-site access Ice Storm 8 12 Ditches Freezing Rain 8 12 Ditches Ice Storm

269 Oil/water seperator Freezing Rain 8 12 Motorized acuators Freezing Rain 8 12 Sampler pump Freezing Rain 8 12 Sluice gates (manual and motorized) Freezing Rain 8 12 HVAC in buildings Low Temperature 12 8 HVAC in buildings Freezing Rain 8 12 Potable water line with backflow preventor Freezing Rain 8 12 Ventilation system (exhaust) Low Temperature 12 8 Ventilation system (exhaust) Freezing Rain 8 12 Two-way radio Ice Storm 8 12 Cellular Phone Ice Storm 8 12 Safety structures (ladders, railings, platforms) Ice Storm 8 12 Personnel (Maintenance/Inspection) Hurricane / Tropical 6 12 Storms Access to facility Freeze/Thaw 12 6 On-site access Freeze/Thaw 12 6 Concrete spillway Extreme Heavy Rainfall 6 12 Gabian basket retaining structure Extreme Heavy Rainfall 6 12 Diversion Chambers Extreme Heavy Rainfall 6 12 Low flow channel Extreme Heavy Rainfall 6 12 High flow channel Extreme Heavy Rainfall 6 12 Inlet and outlet pipes (150mm mm) Extreme Heavy Rainfall 6 12 Ditches Extreme Heavy Rainfall 6 12 Outlet to storm (600mm) Extreme Heavy Rainfall 6 12 Outlet to sanitary (600mm) Extreme Heavy Rainfall

270 Table 5 Juliet Pond Infrastructure Climate Parameter Existing Risk Future Risk Dry storage Pond - vegetated Heavy Rainfall Personnel (Maintenance/Inspection) Hailstorm Access to Facility Snow Accumulation Access On-site Snow Accumulation Dry storage Pond - vegetated Snow Accumulation mm into open ditch Snow Accumulation mm on east side Snow Accumulation Overflow Structure Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall Access to Facility Heavy Snowfall Access On-site Heavy Snowfall Dry storage Pond - vegetated Heavy Snowfall Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access to Facility Heavy Rainfall Access On-site Heavy Rainfall Dry storage Pond - vegetated Rain (Frequency) mm into open ditch Heavy Rainfall mm on east side Heavy Rainfall Outlet Structure Heavy Rainfall Overflow Structure Heavy Rainfall Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation Equipment for Facility Inspection/Maintenance Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Dry storage Pond - vegetated Winter Rain/Rain-on-Snow Two-way radio Lightning Cellular Phone Lightning Personnel (Maintenance/Inspection) Freezing Rain Procedures (Inspections/Maintenance) Freezing Rain Access to Facility Freezing Rain Access On-site Freezing Rain mm on east side Freezing Rain Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Equipment for Facility Inspection/Maintenance Heavy Rainfall Access to Facility Rain (Frequency)

271 Access On-site Rain (Frequency) Security Access - airside Heavy Rainfall mm into open ditch Rain (Frequency) mm on east side Rain (Frequency) Overflow Structure Rain (Frequency) Dry storage Pond - vegetated Heavy 5 day total Rainfall mm into open ditch Heavy 5 day total Rainfall mm on east side Heavy 5 day total Rainfall Overflow Structure Heavy 5 day total Rainfall Two-way radio Ice Storm Cellular Phone Ice Storm Procedures (Inspections/Maintenance) Winter Rain/Rain-on-Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Heavy Snowfall Equipment for Facility Inspection/Maintenance Heavy Snowfall Access to Facility Snow Storm/ Blizzard Access On-site High Wind/ Downburst Access On-site Winter Rain/Rain-on-Snow Access On-site Snow Storm/ Blizzard mm into open ditch Winter Rain/Rain-on-Snow mm on east side Winter Rain/Rain-on-Snow mm on east side Heavy Snowfall Outlet Structure Heavy Snowfall Overflow Structure Winter Rain/Rain-on-Snow Overflow Structure Heavy Snowfall Two-way radio High Wind/ Downburst Cellular Phone High Wind/ Downburst Dry storage Pond - vegetated Drought/Dry Periods Outlet Structure Snow Accumulation Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Heavy 5 day total Rainfall 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Heavy 5 day total Rainfall 8 12 Emergency Procedures (Flood Level Warning) Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Low Temperature 12 8 Equipment for Facility Inspection/Maintenance Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Ice Storm 8 12 Access to Facility Ice Storm 8 12 Access On-site Heavy 5 day total Rainfall 8 12 Access On-site Ice Storm 8 12 Dry storage Pond - vegetated Ice Storm mm into open ditch Freezing Rain mm into open ditch Ice Storm mm on east side Ice Storm 8 12 Outlet Structure Freezing Rain 8 12 Overflow Structure Freezing Rain 8 12 Overflow Structure Ice Storm 8 12 Two-way radio Freezing Rain

272 Cellular Phone Freezing Rain 8 12 Personnel (Maintenance/Inspection) Hurricane / Tropical 6 12 Storms Access to Facility Freeze/Thaw 12 6 Access On-site Freeze/Thaw 12 6 Dry storage Pond - vegetated Extreme Heavy Rainfall mm into open ditch Extreme Heavy Rainfall mm on east side Extreme Heavy Rainfall 6 12 Overflow Structure Extreme Heavy Rainfall

273 Table 6 Moores Facility Infrastructure Climate Parameter Existing Risk Future Risk Personnel (Maintenance/Inspection) Hailstorm Reinforced Concrete tank (cells) Heavy Rainfall Dry Surface Storage Pond 1 - vegetated Heavy Rainfall Dry Surface Storage Pond 2 - vegetated Heavy Rainfall Access to Facility Snow Accumulation On site access Snow Accumulation Reinforced Concrete tank (cells) Snow Accumulation Dry Surface Storage Pond 1 - vegetated Snow Accumulation Dry Surface Storage Pond 2 - vegetated Snow Accumulation Inlet mm Snow Accumulation Inlet mm Snow Accumulation Inlet 3 Snow Accumulation Diversion/bypass (including weir plates) Snow Accumulation Diversion bypass outlet Snow Accumulation Outlet #1 from separator Snow Accumulation Bypass Outlet from tank - 600mm Snow Accumulation Concrete weir - diversion chamber Snow Accumulation Moores Facility Outfall mm Concrete pipe Snow Accumulation Sanitary connection via forcemain Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall On site access Heavy Snowfall Reinforced Concrete tank (cells) Heavy Snowfall Dry Surface Storage Pond 1 - vegetated Heavy Snowfall Dry Surface Storage Pond 2 - vegetated Heavy Snowfall all interior acuators Heavy Snowfall all exterior acuators Heavy Snowfall pumps (sanitary, sample etc) Heavy Snowfall Ventillation System (exhaust + goosenecks) Heavy Snowfall Potable water line - tank Heavy Snowfall Potable water line - separator (backflow valve) Heavy Snowfall Two-way radio Heavy Snowfall Cellular Phone Heavy Snowfall Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access to Facility Heavy Rainfall On site access Heavy Rainfall Reinforced Concrete tank (cells) Rain (Frequency) Dry Surface Storage Pond 1 - vegetated Rain (Frequency) Dry Surface Storage Pond 2 - vegetated Rain (Frequency) Inlet mm Rain (Frequency) Inlet mm Rain (Frequency) Inlet 3 Rain (Frequency)

274 Diversion/bypass (including weir plates) Rain (Frequency) Diversion bypass outlet Rain (Frequency) Outlet #1 from separator Rain (Frequency) Bypass Outlet from tank - 600mm Rain (Frequency) Concrete weir - diversion chamber Rain (Frequency) Moores Facility Outfall mm Concrete pipe Rain (Frequency) Sanitary connection via forcemain Rain (Frequency) Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation Equipment for Facility Inspection/Maintenance Snow Accumulation all interior acuators Snow Accumulation all exterior acuators Snow Accumulation pumps (sanitary, sample etc) Snow Accumulation Ventillation System (exhaust + goosenecks) Snow Accumulation Potable water line - tank Snow Accumulation Potable water line - separator (backflow valve) Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Reinforced Concrete tank (cells) Winter Rain/Rain-on Snow Dry Surface Storage Pond 1 - vegetated Winter Rain/Rain-on Snow Dry Surface Storage Pond 2 - vegetated Winter Rain/Rain-on Snow Inlet mm Winter Rain/Rain-on Snow Inlet mm Winter Rain/Rain-on Snow Inlet 3 Winter Rain/Rain-on Snow Diversion/bypass (including weir plates) Winter Rain/Rain-on Snow Diversion bypass outlet Winter Rain/Rain-on Snow Outlet #1 from separator Winter Rain/Rain-on Snow Bypass Outlet from tank - 600mm Winter Rain/Rain-on Snow Concrete weir - diversion chamber Winter Rain/Rain-on Snow Moores Facility Outfall mm Concrete pipe Winter Rain/Rain-on Snow Sanitary connection via forcemain Winter Rain/Rain-on Snow Personnel (Maintenance/Inspection) Freezing Rain Procedures (Inspections/Maintenance) Freezing Rain Access to Facility Freezing Rain On site access Freezing Rain Inlet mm Heavy 5 day total Rainfall Inlet mm Freezing Rain

275 Inlet mm Heavy 5 day total Rainfall Inlet mm Freezing Rain Inlet 3 Heavy 5 day total Rainfall Inlet 3 Freezing Rain Diversion/bypass (including weir plates) Heavy 5 day total Rainfall Diversion/bypass (including weir plates) Freezing Rain Diversion bypass outlet Heavy 5 day total Rainfall Diversion bypass outlet Freezing Rain Outlet #1 from separator Heavy 5 day total Rainfall Outlet #1 from separator Freezing Rain Bypass Outlet from tank - 600mm Heavy 5 day total Rainfall Bypass Outlet from tank - 600mm Freezing Rain Concrete weir - diversion chamber Heavy 5 day total Rainfall Concrete weir - diversion chamber Freezing Rain Moores Facility Outfall mm Concrete pipe Heavy 5 day total Rainfall Moores Facility Outfall mm Concrete pipe Freezing Rain Sanitary connection via forcemain Heavy 5 day total Rainfall Sanitary connection via forcemain Freezing Rain oil/water separator Cold Wave oil/water separator Ice Storm all interior acuators Cold Wave all exterior acuators Cold Wave pumps (sanitary, sample etc) Cold Wave Ventillation System (exhaust + goosenecks) Cold Wave Potable water line - tank Cold Wave Potable water line - separator (backflow valve) Cold Wave Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Equipment for Facility Inspection/Maintenance Heavy Rainfall On site access Rain (Frequency) Inlet mm Heavy Rainfall Inlet mm Heavy Rainfall Inlet 3 Heavy Rainfall Diversion/bypass (including weir plates) Heavy Rainfall Diversion bypass outlet Heavy Rainfall Outlet #1 from separator Heavy Rainfall Bypass Outlet from tank - 600mm Heavy Rainfall Concrete weir - diversion chamber Heavy Rainfall Moores Facility Outfall mm Concrete pipe Heavy Rainfall Sanitary connection via forcemain Heavy Rainfall Oil/water separator Building (structure ony) Wet Days Control/Electrical Building(structure only) Wet Days Electrical panel High Temperature Electrical panel Heat Wave Reinforced Concrete tank (cells) Heavy 5 day total Rainfall Dry Surface Storage Pond 1 - vegetated Heavy 5 day total Rainfall Dry Surface Storage Pond 2 - vegetated Heavy 5 day total Rainfall

276 oil/water separator Low Temperature all interior acuators Low Temperature all exterior acuators Low Temperature pumps (sanitary, sample etc) Low Temperature Potable water line - tank Low Temperature Potable water line - separator (backflow valve) Low Temperature Procedures (Inspections/Maintenance) Winter Rain/Rain-on Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Winter Rain/Rain-on Snow Emergency Procedures (Flood Level Warning) Heavy Snowfall Equipment for Facility Inspection/Maintenance Heavy Snowfall Access to Facility Snow Storm/ Blizzard Access to Facility Heavy Snowfall On site access High Wind/ Downburst On site access Winter Rain/Rain-on Snow On site access Snow Storm/ Blizzard Inlet mm Heavy Snowfall Inlet mm Heavy Snowfall Inlet 3 Heavy Snowfall Diversion/bypass (including weir plates) Heavy Snowfall Diversion bypass outlet Heavy Snowfall Outlet #1 from separator Heavy Snowfall Bypass Outlet from tank - 600mm Heavy Snowfall Concrete weir - diversion chamber Heavy Snowfall Moores Facility Outfall mm Concrete pipe Heavy Snowfall Sanitary connection via forcemain Heavy Snowfall all interior acuators Snow Storm/ Blizzard all exterior acuators Snow Storm/ Blizzard pumps (sanitary, sample etc) Snow Storm/ Blizzard Ventillation System (exhaust + goosenecks) Snow Storm/ Blizzard Potable water line - tank Snow Storm/ Blizzard Potable water line - separator (backflow valve) Snow Storm/ Blizzard Electrical panel Lightning Two-way radio High Wind/ Downburst Two-way radio Lightning Cellular Phone High Wind/ Downburst Cellular Phone Lightning Dry Surface Storage Pond 1 - vegetated Drought/Dry Periods Dry Surface Storage Pond 2 - vegetated Drought/Dry Periods Oil/water separator Building (structure ony) Snow Accumulation oil/water separator Snow Accumulation Control/Electrical Building(structure only) Snow Accumulation Gas Detection System Snow Accumulation PLC/SCADA System (including Comm Conne) Snow Accumulation Fire Alarm Snow Accumulation Level Indicators Snow Accumulation

277 Facility Alarms (Active 8 System) Snow Accumulation Phone Line (alarms + Phone) Snow Accumulation Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Heavy 5 day total Rainfall 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Heavy 5 day total Rainfall 8 12 Emergency Procedures (Flood Level Warning) Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Low Temperature 12 8 Equipment for Facility Inspection/Maintenance Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Ice Storm 8 12 Access to Facility Ice Storm 8 12 On site access Heavy 5 day total Rainfall 8 12 On site access Ice Storm 8 12 oil/water separator Freezing Rain 8 12 all interior acuators Freezing Rain 8 12 all exterior acuators Freezing Rain 8 12 pumps (sanitary, sample etc) Freezing Rain 8 12 Ventillation System (exhaust + goosenecks) Low Temperature 12 8 Ventillation System (exhaust + goosenecks) Freezing Rain 8 12 Potable water line - tank Freezing Rain 8 12 Potable water line - separator (backflow valve) Freezing Rain 8 12 Two-way radio Ice Storm 8 12 Cellular Phone Ice Storm 8 12 Personnel (Maintenance/Inspection) Hurricane / Tropical 6 12 Storms Access to Facility Freeze/Thaw 12 6 On site access Freeze/Thaw 12 6 Inlet mm Extreme Heavy Rainfall 6 12 Inlet mm Extreme Heavy Rainfall 6 12 Inlet 3 Extreme Heavy Rainfall 6 12 Diversion/bypass (including weir plates) Extreme Heavy Rainfall 6 12 Diversion bypass outlet Extreme Heavy Rainfall 6 12 Outlet #1 from separator Extreme Heavy Rainfall 6 12 Bypass Outlet from tank - 600mm Extreme Heavy Rainfall 6 12 Concrete weir - diversion chamber Extreme Heavy Rainfall 6 12 Moores Facility Outfall mm Concrete pipe Extreme Heavy Rainfall 6 12 Sanitary connection via forcemain Extreme Heavy Rainfall

278 Table 7 Pond 2 Infrastructure Climate Parameter Existing Risk Future Risk Personnel (Maintenance/Inspection) Hailstorm Access to Facility Snow Accumulation Access On-site Snow Accumulation Concrete Pond Snow Accumulation Concrete Blocks Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall Access to Facility Heavy Snowfall Access On-site Heavy Snowfall Concrete Pond Heavy Snowfall sluice gate valve for high flow Heavy Snowfall Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access to Facility Heavy Rainfall Access On-site Heavy Rainfall Concrete Pond Heavy Rainfall Concrete Blocks Heavy Rainfall Concrete Blocks Rain (Frequency) three stormwater inlets Heavy Rainfall Outlet pipe (high and low flow) Heavy Rainfall Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation three stormwater inlets Snow Accumulation Outlet pipe (high and low flow) Snow Accumulation sluice gate valve for high flow Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Two-way radio Lightning Cellular Phone Lightning Personnel (Maintenance/Inspection) Freezing Rain Emergency Procedures (Flood Level Warning) Freezing Rain Access to Facility Freezing Rain Access On-site Freezing Rain Highway Freezing Rain Concrete Pond Freezing Rain Concrete Blocks Freezing Rain three stormwater inlets Freezing Rain Outlet pipe (high and low flow) Freezing Rain sluice gate valve for high flow Freezing Rain Platform - ladder access Freezing Rain Personnel (Maintenance/Inspection) High Temperature

279 Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Access On-site Rain (Frequency) Highway Heavy Rainfall three stormwater inlets Rain (Frequency) Outlet pipe (high and low flow) Rain (Frequency) sluice gate valve for high flow Heavy Rainfall Platform - ladder access Rain (Frequency) sluice gate valve for high flow Low Temperature sluice gate valve for high flow Ice Storm Two-way radio Ice Storm Cellular Phone Ice Storm Procedures (Inspections/Maintenance) Winter Rain/Rain-on-Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Heavy Snowfall Access to Facility Heavy Fog Access On-site High Wind/ Downburst Access On-site Winter Rain/Rain-on-Snow Access On-site Snow Storm/ Blizzard Highway Heavy Snowfall Concrete Pond Winter Rain/Rain-on-Snow Concrete Blocks Winter Rain/Rain-on-Snow Concrete Blocks Heavy Snowfall three stormwater inlets Winter Rain/Rain-on-Snow three stormwater inlets Heavy Snowfall Outlet pipe (high and low flow) Winter Rain/Rain-on-Snow Outlet pipe (high and low flow) Heavy Snowfall sluice gate valve for high flow Lightning Two-way radio High Wind/ Downburst Two-way radio Heavy Snowfall Cellular Phone High Wind/ Downburst Cellular Phone Heavy Snowfall Platform - ladder access Winter Rain/Rain-on-Snow Concrete Pond Drought/Dry Periods Concrete Blocks Drought/Dry Periods Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Heavy 5 day total Rainfall 8 12 Procedures (Inspections/Maintenance) Freezing Rain 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Heavy 5 day total Rainfall 8 12 Emergency Procedures (Flood Level Warning) Ice Storm 8 12 Access to Facility Low Temperature 12 8 Access to Facility Ice Storm 8 12 Access On-site Heavy 5 day total Rainfall 8 12 Access On-site Ice Storm 8 12 Highway Ice Storm 8 12 Concrete Pond Heavy 5 day total Rainfall

280 Concrete Pond Ice Storm 8 12 Concrete Blocks Heavy 5 day total Rainfall 8 12 Concrete Blocks Ice Storm 8 12 three stormwater inlets Heavy 5 day total Rainfall 8 12 three stormwater inlets Ice Storm 8 12 Outlet pipe (high and low flow) Heavy 5 day total Rainfall 8 12 Outlet pipe (high and low flow) Ice Storm 8 12 sluice gate valve for high flow Cold Wave 12 8 Two-way radio Freezing Rain 8 12 Cellular Phone Freezing Rain 8 12 Personnel (Maintenance/Inspection) Hurricane / Tropical Storms

281 Table 8 Pond 4 Infrastructure Climate Parameter Existing Risk Future Risk Personnel (Maintenance/Inspection) Hailstorm Access to Facility Snow Accumulation Access On-site Snow Accumulation Concrete Pond Snow Accumulation Concrete Blocks Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall Access to Facility Heavy Snowfall Access On-site Heavy Snowfall Concrete Pond Heavy Snowfall sluice gate valve for high flow Heavy Snowfall Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access to Facility Heavy Rainfall Access On-site Heavy Rainfall Concrete Pond Heavy Rainfall Concrete Blocks Heavy Rainfall Concrete Blocks Rain (Frequency) three stormwater inlets Heavy Rainfall Outlet pipe (high and low flow) Heavy Rainfall Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation three stormwater inlets Snow Accumulation Outlet pipe (high and low flow) Snow Accumulation sluice gate valve for high flow Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Two-way radio Lightning Cellular Phone Lightning Personnel (Maintenance/Inspection) Freezing Rain Emergency Procedures (Flood Level Warning) Freezing Rain Access to Facility Freezing Rain Access On-site Freezing Rain Highway Freezing Rain Concrete Pond Freezing Rain Concrete Blocks Freezing Rain three stormwater inlets Freezing Rain Outlet pipe (high and low flow) Freezing Rain sluice gate valve for high flow Freezing Rain Platform - ladder access Freezing Rain Personnel (Maintenance/Inspection) High Temperature

282 Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Access On-site Rain (Frequency) Highway Heavy Rainfall three stormwater inlets Rain (Frequency) Outlet pipe (high and low flow) Rain (Frequency) sluice gate valve for high flow Heavy Rainfall Platform - ladder access Rain (Frequency) sluice gate valve for high flow Low Temperature sluice gate valve for high flow Ice Storm Two-way radio Ice Storm Cellular Phone Ice Storm Procedures (Inspections/Maintenance) Winter Rain/Rain-on-Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Heavy Snowfall Access to Facility Heavy Fog Access On-site High Wind/ Downburst Access On-site Winter Rain/Rain-on-Snow Access On-site Snow Storm/ Blizzard Highway Heavy Snowfall Concrete Pond Winter Rain/Rain-on-Snow Concrete Blocks Winter Rain/Rain-on-Snow Concrete Blocks Heavy Snowfall three stormwater inlets Winter Rain/Rain-on-Snow three stormwater inlets Heavy Snowfall Outlet pipe (high and low flow) Winter Rain/Rain-on-Snow Outlet pipe (high and low flow) Heavy Snowfall sluice gate valve for high flow Lightning Two-way radio High Wind/ Downburst Two-way radio Heavy Snowfall Cellular Phone High Wind/ Downburst Cellular Phone Heavy Snowfall Platform - ladder access Winter Rain/Rain-on-Snow Concrete Pond Drought/Dry Periods Concrete Blocks Drought/Dry Periods Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Heavy 5 day total Rainfall 8 12 Procedures (Inspections/Maintenance) Freezing Rain 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Heavy 5 day total Rainfall 8 12 Emergency Procedures (Flood Level Warning) Ice Storm 8 12 Access to Facility Low Temperature 12 8 Access to Facility Ice Storm 8 12 Access On-site Heavy 5 day total Rainfall 8 12 Access On-site Ice Storm 8 12 Highway Ice Storm 8 12 Concrete Pond Heavy 5 day total Rainfall

283 Concrete Pond Ice Storm 8 12 Concrete Blocks Heavy 5 day total Rainfall 8 12 Concrete Blocks Ice Storm 8 12 three stormwater inlets Heavy 5 day total Rainfall 8 12 three stormwater inlets Ice Storm 8 12 Outlet pipe (high and low flow) Heavy 5 day total Rainfall 8 12 Outlet pipe (high and low flow) Ice Storm 8 12 sluice gate valve for high flow Cold Wave 12 8 Two-way radio Freezing Rain 8 12 Cellular Phone Freezing Rain 8 12 Personnel (Maintenance/Inspection) Hurricane / Tropical Storms

284 Table 9 SWM4 Pond Infrastructure Climate Parameter Existing Risk Future Risk Personnel (Maintenance/Inspection) Hailstorm Access to Facility - berm Snow Accumulation Access On-site (Berm to Platform) Snow Accumulation Dry Surface Storage Pond - vegetated Snow Accumulation Ditch from behind CLS Snow Accumulation Wooden Platform Hailstorm Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall Dry Surface Storage Pond - vegetated Heavy Snowfall sanitary outlet - valve 375 mm Heavy Snowfall Wooden Platform Lightning Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access to Facility - berm Heavy Rainfall Access On-site (Berm to Platform) Heavy Rainfall Dry Surface Storage Pond - vegetated Heavy Rainfall Ditch from behind CLS Heavy Rainfall mm inlet Heavy Rainfall mm inlet Heavy Rainfall mm inlet Heavy Rainfall Ditch from groundside snow dump Heavy Rainfall Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation Equipment for Facility Inspection/Maintenance Snow Accumulation mm inlet Snow Accumulation Ditch from groundside snow dump Snow Accumulation sanitary outlet - valve 375 mm Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Wooden Platform Snow Accumulation Dry Surface Storage Pond - vegetated Winter Rain/Rain-on-Snow sluice gate valve with turning wheel (900mm) Lightning sanitary outlet - valve 375 mm Lightning Two-way radio Lightning Cellular Phone Lightning Personnel (Maintenance/Inspection) Freezing Rain Procedures (Inspections/Maintenance) Freezing Rain Access On-site (Berm to Platform) Freezing Rain sluice gate valve with turning wheel (900mm) Freezing Rain

285 sluice gate valve with turning wheel (900mm) Ice Storm sanitary outlet - valve 375 mm Freezing Rain sanitary outlet - valve 375 mm Ice Storm Wooden Platform Freezing Rain Wooden Platform Ice Storm Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Equipment for Facility Inspection/Maintenance Heavy Rainfall Access to Facility - berm Rain (Frequency) Access On-site (Berm to Platform) Rain (Frequency) Ditch from behind CLS Rain (Frequency) Ditch from groundside snow dump Rain (Frequency) sluice gate valve with turning wheel (900mm) Heavy Rainfall sanitary outlet - valve 375 mm Heavy Rainfall Emergency Procedures (Flood Level Warning) Ice Storm Access On-site (Berm to Platform) Ice Storm Ditch from behind CLS Heavy 5 day total Rainfall mm inlet Heavy 5 day total Rainfall mm inlet Heavy 5 day total Rainfall Ditch from groundside snow dump Heavy 5 day total Rainfall sluice gate valve with turning wheel (900mm) Low Temperature sluice gate valve with turning wheel (900mm) Cold Wave sanitary outlet - valve 375 mm Low Temperature sanitary outlet - valve 375 mm Cold Wave Two-way radio Ice Storm Cellular Phone Ice Storm Procedures (Inspections/Maintenance) Winter Rain/Rain-on-Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Heavy Snowfall Access to Facility - berm High Wind/ Downburst Access to Facility - berm Winter Rain/Rain-on-Snow Access On-site (Berm to Platform) Winter Rain/Rain-on-Snow Ditch from behind CLS Winter Rain/Rain-on-Snow Ditch from groundside snow dump Winter Rain/Rain-on-Snow sluice gate valve with turning wheel (900mm) Winter Rain/Rain-on-Snow sanitary outlet - valve 375 mm Winter Rain/Rain-on-Snow sanitary outlet - valve 375 mm Snow Storm/ Blizzard Two-way radio High Wind/ Downburst Cellular Phone High Wind/ Downburst Wooden Platform Snow Storm/ Blizzard Dry Surface Storage Pond - vegetated Drought/Dry Periods mm inlet Snow Accumulation mm inlet Snow Accumulation sluice gate valve with turning wheel (900mm) Snow Accumulation Personnel (Maintenance/Inspection) Hurricane / Tropical

286 Storms Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Low Temperature 12 8 Equipment for Facility Inspection/Maintenance Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Ice Storm 8 12 Access to Facility - berm Heavy 5 day total Rainfall 8 12 Access to Facility - berm Freezing Rain 8 12 Access to Facility - berm Ice Storm 8 12 Dry Surface Storage Pond - vegetated Heavy 5 day total Rainfall 8 12 Dry Surface Storage Pond - vegetated Ice Storm 8 12 Ditch from behind CLS Ice Storm mm inlet Heavy 5 day total Rainfall 8 12 Ditch from groundside snow dump Ice Storm 8 12 Two-way radio Freezing Rain 8 12 Cellular Phone Freezing Rain 8 12 Emergency Procedures (Flood Level Warning) Extreme Heavy Rainfall 6 12 Access to Facility - berm Freeze/Thaw 12 6 Ditch from behind CLS Extreme Heavy Rainfall mm inlet Extreme Heavy Rainfall mm inlet Extreme Heavy Rainfall mm inlet Extreme Heavy Rainfall 6 12 Ditch from groundside snow dump Extreme Heavy Rainfall 6 12 sluice gate valve with turning wheel (900mm) Hurricane / Tropical 6 12 Storms Wooden Platform Hurricane / Tropical Storms

287 Table 10 SWM5 Pond Infrastructure Climate Parameter Existing Risk Future Risk Personnel (Maintenance/Inspection) Hailstorm Access road - berm Snow Accumulation Dry Surface Storage Pond - vegetated Snow Accumulation mm Riprap Ditch Snow Accumulation mm Riprap Ditch Snow Accumulation mm Riprap Ditch Snow Accumulation mm CSP (Furthest South) Snow Accumulation mm CSP (South of 300 mm CP) Snow Accumulation mm CP (Furthest North) Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall Dry Surface Storage Pond - vegetated Heavy Snowfall Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access road - berm Heavy Rainfall Dry Surface Storage Pond - vegetated Heavy Rainfall mm Riprap Ditch Heavy Rainfall mm Riprap Ditch Heavy Rainfall mm Riprap Ditch Heavy Rainfall mm CSP (Furthest South) Heavy Rainfall mm CSP (South of 300 mm CP) Heavy Rainfall mm CP (Furthest North) Heavy Rainfall Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation Equipment for Facility Inspection/Maintenance Snow Accumulation Dry Surface Storage Pond - vegetated Winter Rain/Rain-on-Snow Two-way radio Lightning Cellular Phone Lightning Personnel (Maintenance/Inspection) Freezing Rain Procedures (Inspections/Maintenance) Freezing Rain Access road - berm Freezing Rain Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Equipment for Facility Inspection/Maintenance Heavy Rainfall Access road - berm Rain (Frequency) mm Riprap Ditch Rain (Frequency) mm Riprap Ditch Rain (Frequency) mm Riprap Ditch Rain (Frequency) mm CSP (Furthest South) Rain (Frequency)

288 300 mm CSP (South of 300 mm CP) Rain (Frequency) mm CP (Furthest North) Rain (Frequency) Emergency Procedures (Flood Level Warning) Ice Storm Access road - berm Ice Storm mm Riprap Ditch Heavy 5 day total Rainfall mm Riprap Ditch Heavy 5 day total Rainfall mm Riprap Ditch Heavy 5 day total Rainfall mm CSP (Furthest South) Heavy 5 day total Rainfall mm CSP (South of 300 mm CP) Heavy 5 day total Rainfall mm CP (Furthest North) Heavy 5 day total Rainfall Two-way radio Ice Storm Cellular Phone Ice Storm Procedures (Inspections/Maintenance) Winter Rain/Rain-on-Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Heavy Snowfall Access road - berm High Wind/ Downburst Access road - berm Winter Rain/Rain-on-Snow Access road - berm Heavy Snowfall mm Riprap Ditch Winter Rain/Rain-on-Snow mm Riprap Ditch Winter Rain/Rain-on-Snow mm Riprap Ditch Winter Rain/Rain-on-Snow Two-way radio High Wind/ Downburst Cellular Phone High Wind/ Downburst Dry Surface Storage Pond - vegetated Drought/Dry Periods Personnel (Maintenance/Inspection) Hurricane / Tropical 7 14 Storms Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Equipment for Facility Inspection/Maintenance Low Temperature 12 8 Equipment for Facility Inspection/Maintenance Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Ice Storm 8 12 Dry Surface Storage Pond - vegetated Heavy 5 day total Rainfall 8 12 Dry Surface Storage Pond - vegetated Ice Storm mm Riprap Ditch Ice Storm mm Riprap Ditch Ice Storm mm Riprap Ditch Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Extreme Heavy Rainfall mm Riprap Ditch Extreme Heavy Rainfall mm Riprap Ditch Extreme Heavy Rainfall mm Riprap Ditch Extreme Heavy Rainfall mm CSP (Furthest South) Extreme Heavy Rainfall mm CSP (South of 300 mm CP) Extreme Heavy Rainfall mm CP (Furthest North) Extreme Heavy Rainfall

289 Table 11 SWM6 Pond Infrastructure Climate Parameter Existing Risk Future Risk Personnel (Maintenance/Inspection) Hailstorm Access road to Facility Snow Accumulation Access on-site Snow Accumulation Dry Surface Storage Pond - vegetated Snow Accumulation Ditch from 1050 mm approximately 12 o'clock Snow Accumulation Ditch from 600 mm approximately 1 o'clock Snow Accumulation Ditch and riprap structure from along Service Road east side Snow Accumulation Three- Riprap structures from 300 mm roadway drainage on Snow Accumulation southside of pond Riprap structure from 450 mm roadway drainage on Snow Accumulation southside of pond Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall Dry Surface Storage Pond - vegetated Heavy Snowfall sanitary outlet Heavy Snowfall Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access road to Facility Heavy Rainfall Access on-site Heavy Rainfall Dry Surface Storage Pond - vegetated Heavy Rainfall Ditch from 1050 mm approximately 12 o'clock Heavy Rainfall Ditch from 600 mm approximately 1 o'clock Heavy Rainfall Ditch and riprap structure from along Service Road east side Heavy Rainfall Three- Riprap structures from 300 mm roadway drainage on Heavy Rainfall southside of pond Riprap structure from 450 mm roadway drainage on Heavy Rainfall southside of pond Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation Equipment for Facility Inspection/Maintenance Snow Accumulation sanitary outlet Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Dry Surface Storage Pond - vegetated Winter Rain/Rainon-Snow Personnel (Maintenance/Inspection) Freezing Rain Procedures (Inspections/Maintenance) Freezing Rain sluice gate valve Ice Storm Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Equipment for Facility Inspection/Maintenance Heavy Rainfall

290 Access road to Facility Rain (Frequency) Access on-site Rain (Frequency) Security Access - airside Heavy Rainfall Ditch from 1050 mm approximately 12 o'clock Rain (Frequency) Ditch from 600 mm approximately 1 o'clock Rain (Frequency) Ditch and riprap structure from along Service Road east side Rain (Frequency) Three- Riprap structures from 300 mm roadway drainage on Rain (Frequency) southside of pond Riprap structure from 450 mm roadway drainage on Rain (Frequency) southside of pond sluice gate valve Heavy Rainfall sanitary outlet Heavy Rainfall diversion chamber (not accessible) Heavy Rainfall Emergency Procedures (Flood Level Warning) Ice Storm Access road to Facility Ice Storm Access on-site Ice Storm Ditch from 1050 mm approximately 12 o'clock Heavy 5 day total Rainfall Ditch from 600 mm approximately 1 o'clock Heavy 5 day total Rainfall Ditch and riprap structure from along Service Road east side Heavy 5 day total Rainfall Three- Riprap structures from 300 mm roadway drainage on Heavy 5 day total southside of pond Rainfall Riprap structure from 450 mm roadway drainage on Heavy 5 day total southside of pond Rainfall sluice gate valve Low Temperature sanitary outlet Low Temperature Procedures (Inspections/Maintenance) Winter Rain/Rainon-Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Heavy Snowfall Access road to Facility Snow Storm/ Blizzard Access road to Facility Heavy Snowfall Access on-site Snow Storm/ Blizzard Access on-site Heavy Snowfall Ditch from 1050 mm approximately 12 o'clock Winter Rain/Rainon-Snow Ditch from 600 mm approximately 1 o'clock Winter Rain/Rainon-Snow Ditch and riprap structure from along Service Road east side Winter Rain/Rainon-Snow Three- Riprap structures from 300 mm roadway drainage on Winter Rain/Rainon-Snow southside of pond Riprap structure from 450 mm roadway drainage on Winter Rain/Rainon-Snow southside of pond sanitary outlet Snow Storm/ Blizzard Two-way radio High Wind/

291 Downburst Two-way radio Lightning Cellular Phone High Wind/ Downburst Cellular Phone Lightning Dry Surface Storage Pond - vegetated Drought/Dry Periods sluice gate valve Snow Accumulation Personnel (Maintenance/Inspection) Hurricane / Tropical 7 14 Storms Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Low Temperature 12 8 Equipment for Facility Inspection/Maintenance Low Temperature 12 8 Equipment for Facility Inspection/Maintenance Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Ice Storm 8 12 Access on-site Freezing Rain 8 12 Dry Surface Storage Pond - vegetated Heavy 5 day total 8 12 Rainfall Dry Surface Storage Pond - vegetated Ice Storm 8 12 Ditch from 1050 mm approximately 12 o'clock Ice Storm 8 12 Ditch from 600 mm approximately 1 o'clock Ice Storm 8 12 Ditch and riprap structure from along Service Road east side Ice Storm 8 12 Three- Riprap structures from 300 mm roadway drainage on Ice Storm 8 12 southside of pond Riprap structure from 450 mm roadway drainage on Ice Storm 8 12 southside of pond sluice gate valve Freezing Rain 8 12 sanitary outlet Freezing Rain 8 12 diversion chamber (not accessible) Freezing Rain 8 12 Two-way radio Ice Storm 8 12 Cellular Phone Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Extreme Heavy 6 12 Rainfall Ditch from 1050 mm approximately 12 o'clock Extreme Heavy 6 12 Rainfall Ditch from 600 mm approximately 1 o'clock Extreme Heavy 6 12 Rainfall Ditch and riprap structure from along Service Road east side Extreme Heavy 6 12 Rainfall Three- Riprap structures from 300 mm roadway drainage on Extreme Heavy 6 12 southside of pond Rainfall Riprap structure from 450 mm roadway drainage on Extreme Heavy 6 12 southside of pond Rainfall sluice gate valve Hurricane / Tropical Storms

292 Table 12 SWM16 Pond Infrastructure Climate Parameter Existing Risk Future Risk Personnel (Maintenance/Inspection) Hailstorm Dry storage Pond - vegetated Heavy Rainfall Access to Facility Snow Accumulation Access On-site Snow Accumulation Dry storage Pond - vegetated Snow Accumulation Open ditch with gabion Snow Accumulation Outlet structure with Hickenbottom Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall Access to Facility Heavy Snowfall Access On-site Heavy Snowfall Dry storage Pond - vegetated Heavy Snowfall Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access to Facility Heavy Rainfall Access On-site Heavy Rainfall Open ditch with gabion Heavy Rainfall Outlet structure with Hickenbottom Heavy Rainfall Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation Equipment for Facility Inspection/Maintenance Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Dry storage Pond - vegetated Winter Rain/Rain-on-Snow Two-way radio Lightning Cellular Phone Lightning Personnel (Maintenance/Inspection) Freezing Rain Procedures (Inspections/Maintenance) Freezing Rain Access to Facility Freezing Rain Access On-site Freezing Rain Open ditch with gabion Heavy 5 day total Rainfall Outlet structure with Hickenbottom Heavy 5 day total Rainfall Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Equipment for Facility Inspection/Maintenance Heavy Rainfall Access to Facility Rain (Frequency) Access On-site Rain (Frequency) Security Access - airside Heavy Rainfall Open ditch with gabion Rain (Frequency)

293 Outlet structure with Hickenbottom Rain (Frequency) Personnel (Maintenance/Inspection) Heavy 5 day total Rainfall Procedures (Inspections/Maintenance) Heavy 5 day total Rainfall Dry storage Pond - vegetated Heavy 5 day total Rainfall Two-way radio Ice Storm Cellular Phone Ice Storm Procedures (Inspections/Maintenance) Winter Rain/Rain-on-Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Heavy Snowfall Equipment for Facility Inspection/Maintenance Heavy Snowfall Access to Facility Snow Storm/ Blizzard Access On-site High Wind/ Downburst Access On-site Winter Rain/Rain-on-Snow Access On-site Snow Storm/ Blizzard Open ditch with gabion Winter Rain/Rain-on-Snow Outlet structure with Hickenbottom Winter Rain/Rain-on-Snow Two-way radio High Wind/ Downburst Cellular Phone High Wind/ Downburst Dry storage Pond - vegetated Drought/Dry Periods Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Heavy 5 day total Rainfall 8 12 Emergency Procedures (Flood Level Warning) Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Low Temperature 12 8 Equipment for Facility Inspection/Maintenance Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Ice Storm 8 12 Access to Facility Ice Storm 8 12 Access On-site Heavy 5 day total Rainfall 8 12 Access On-site Ice Storm 8 12 Dry storage Pond - vegetated Freezing Rain 8 12 Dry storage Pond - vegetated Ice Storm 8 12 Open ditch with gabion Freezing Rain 8 12 Open ditch with gabion Ice Storm 8 12 Outlet structure with Hickenbottom Freezing Rain 8 12 Two-way radio Freezing Rain 8 12 Cellular Phone Freezing Rain 8 12 Personnel (Maintenance/Inspection) Hurricane / Tropical 6 12 Storms Access to Facility Freeze/Thaw 12 6 Access On-site Freeze/Thaw 12 6 Open ditch with gabion Extreme Heavy Rainfall 6 12 Outlet structure with Hickenbottom Extreme Heavy Rainfall

294 Table 13 SWMA14 Pond Infrastructure Climate Parameter Existing Risk Future Risk Dry Surface Storage Pond - vegetated Heavy Rainfall Personnel (Maintenance/Inspection) Hailstorm Access road Snow Accumulation Access on-site Snow Accumulation Dry Surface Storage Pond - vegetated Snow Accumulation open ditch on West Side Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Maintenance/Inspection) Heavy Snowfall Access road Heavy Snowfall Access on-site Heavy Snowfall Dry Surface Storage Pond - vegetated Heavy Snowfall Procedures (Maintenance/Inspection) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access road Heavy Rainfall Access on-site Heavy Rainfall Dry Surface Storage Pond - vegetated Rain (Frequency) open ditch on West Side Heavy Rainfall mm on west side from airside Heavy Rainfall Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Maintenance/Inspection) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation Equipment for Facility Inspection/Maintenance Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Dry Surface Storage Pond - vegetated Winter Rain/Rain-on-Snow Two-way radio Lightning Cellular Phone Lightning Personnel (Maintenance/Inspection) Freezing Rain Access road Freezing Rain Access on-site Freezing Rain Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Maintenance/Inspection) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Equipment for Facility Inspection/Maintenance Heavy Rainfall Access road Rain (Frequency) Access on-site Rain (Frequency) open ditch on West Side Rain (Frequency) Dry Surface Storage Pond - vegetated Heavy 5 day total Rainfall open ditch on West Side Heavy 5 day total Rainfall Two-way radio Ice Storm Cellular Phone Ice Storm

295 Procedures (Maintenance/Inspection) Winter Rain/Rain-on-Snow Procedures (Maintenance/Inspection) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Heavy Snowfall Equipment for Facility Inspection/Maintenance Heavy Snowfall Access road Snow Storm/ Blizzard Access on-site High Wind/ Downburst Access on-site Winter Rain/Rain-on-Snow Access on-site Snow Storm/ Blizzard open ditch on West Side Winter Rain/Rain-on-Snow Two-way radio High Wind/ Downburst Cellular Phone High Wind/ Downburst Dry Surface Storage Pond - vegetated Drought/Dry Periods mm on west side from airside Snow Accumulation Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Maintenance/Inspection) Heavy 5 day total Rainfall 8 12 Procedures (Maintenance/Inspection) Freezing Rain 8 12 Procedures (Maintenance/Inspection) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Heavy 5 day total Rainfall 8 12 Emergency Procedures (Flood Level Warning) Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Low Temperature 12 8 Equipment for Facility Inspection/Maintenance Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Ice Storm 8 12 Access road Ice Storm 8 12 Access on-site Heavy 5 day total Rainfall 8 12 Access on-site Ice Storm 8 12 Dry Surface Storage Pond - vegetated Freezing Rain 8 12 Dry Surface Storage Pond - vegetated Ice Storm 8 12 open ditch on West Side Ice Storm mm on west side from airside Heavy 5 day total Rainfall 8 12 Two-way radio Freezing Rain 8 12 Cellular Phone Freezing Rain 8 12 Personnel (Maintenance/Inspection) Hurricane / Tropical 6 12 Storms Access road Freeze/Thaw 12 6 Access on-site Freeze/Thaw 12 6 Dry Surface Storage Pond - vegetated Extreme Heavy Rainfall 6 12 open ditch on West Side Extreme Heavy Rainfall mm on west side from airside Extreme Heavy Rainfall

296 Table 14 WM4A Pond Infrastructure Climate Parameter Existing Risk Future Risk Dry Surface storage Pond - vegetated Heavy Rainfall Personnel (Maintenance/Inspection) Hailstorm Open ditch from Derry Road Heavy Rainfall Open ditch from GAA Heavy Rainfall Access to Facility Snow Accumulation Access On-site Snow Accumulation Dry Surface storage Pond - vegetated Snow Accumulation Open ditch from Derry Road Snow Accumulation Open ditch from GAA Snow Accumulation mm sanitary sewer connection Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall Access to Facility Heavy Snowfall Access On-site Heavy Snowfall Dry Surface storage Pond - vegetated Heavy Snowfall sluice gate valve via T-bar key Heavy Snowfall sanitary outlet - valve 300mm Heavy Snowfall Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access to Facility Heavy Rainfall Access On-site Heavy Rainfall Dry Surface storage Pond - vegetated Rain (Frequency) mm sanitary sewer connection Heavy Rainfall sluice gate valve via T-bar key Heavy Rainfall sanitary outlet - valve 300mm Heavy Rainfall Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation Equipment for Facility Inspection/Maintenance Snow Accumulation sluice gate valve via T-bar key Snow Accumulation sanitary outlet - valve 300mm Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Dry Surface storage Pond - vegetated Winter Rain/Rain-on-Snow Two-way radio Lightning Cellular Phone Lightning Personnel (Maintenance/Inspection) Freezing Rain Procedures (Inspections/Maintenance) Freezing Rain Access to Facility Freezing Rain Access On-site Freezing Rain sluice gate valve via T-bar key Freezing Rain sanitary outlet - valve 300mm Freezing Rain

297 Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Equipment for Facility Inspection/Maintenance Heavy Rainfall Access to Facility Rain (Frequency) Access On-site Rain (Frequency) Security Access - airside Heavy Rainfall Open ditch from Derry Road Rain (Frequency) Open ditch from GAA Rain (Frequency) mm sanitary sewer connection Rain (Frequency) Dry Surface storage Pond - vegetated Heavy 5 day total Rainfall Open ditch from Derry Road Heavy 5 day total Rainfall Open ditch from GAA Heavy 5 day total Rainfall mm sanitary sewer connection Heavy 5 day total Rainfall sluice gate valve via T-bar key Low Temperature sluice gate valve via T-bar key Ice Storm sanitary outlet - valve 300mm Low Temperature sanitary outlet - valve 300mm Ice Storm Two-way radio Ice Storm Cellular Phone Ice Storm Procedures (Inspections/Maintenance) Winter Rain/Rain-on-Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Heavy Snowfall Equipment for Facility Inspection/Maintenance Heavy Snowfall Access to Facility Snow Storm/ Blizzard Access On-site High Wind/ Downburst Access On-site Winter Rain/Rain-on-Snow Access On-site Snow Storm/ Blizzard Open ditch from Derry Road Winter Rain/Rain-on-Snow Open ditch from GAA Winter Rain/Rain-on-Snow mm sanitary sewer connection Winter Rain/Rain-on-Snow mm sanitary sewer connection Heavy Snowfall sluice gate valve via T-bar key Lightning sanitary outlet - valve 300mm Lightning Two-way radio High Wind/ Downburst Cellular Phone High Wind/ Downburst Security Access - airside Snow Accumulation Dry Surface storage Pond - vegetated Drought/Dry Periods Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Heavy 5 day total Rainfall 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Heavy 5 day total Rainfall 8 12 Emergency Procedures (Flood Level Warning) Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Low Temperature 12 8 Equipment for Facility Inspection/Maintenance Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Ice Storm 8 12 Access to Facility Ice Storm

298 Access On-site Heavy 5 day total Rainfall 8 12 Access On-site Ice Storm 8 12 Dry Surface storage Pond - vegetated Ice Storm 8 12 Open ditch from Derry Road Freezing Rain 8 12 Open ditch from Derry Road Ice Storm 8 12 Open ditch from GAA Freezing Rain 8 12 Open ditch from GAA Ice Storm mm sanitary sewer connection Freezing Rain mm sanitary sewer connection Ice Storm 8 12 sluice gate valve via T-bar key Cold Wave 12 8 sanitary outlet - valve 300mm Cold Wave 12 8 Two-way radio Freezing Rain 8 12 Cellular Phone Freezing Rain 8 12 Personnel (Maintenance/Inspection) Hurricane / Tropical 6 12 Storms Access to Facility Freeze/Thaw 12 6 Access On-site Freeze/Thaw 12 6 Dry Surface storage Pond - vegetated Extreme Heavy Rainfall 6 12 Dry Surface storage Pond - vegetated Hurricane / Tropical 6 12 Storms Open ditch from Derry Road Extreme Heavy Rainfall 6 12 Open ditch from GAA Extreme Heavy Rainfall mm sanitary sewer connection Extreme Heavy Rainfall

299 Table 15 Spring Creek Culvert Infrastructure Climate Parameter Existing Risk Future Risk Personnel (Maintenance/Inspection) Hailstorm Access to Facility Snow Accumulation Access On-site Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall Access to Facility Heavy Snowfall Access On-site Heavy Snowfall Access to Facility Heavy Rainfall Access On-site Heavy Rainfall Upstream rip-rap Heavy Rainfall Downstream rip-rap Heavy Rainfall culvert inlet Heavy Rainfall Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Two-way radio Lightning Cellular Phone Lightning Personnel (Maintenance/Inspection) Freezing Rain Procedures (Inspections/Maintenance) Freezing Rain Access to Facility Freezing Rain Access On-site Freezing Rain Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Access to Facility Rain (Frequency) Access On-site Rain (Frequency) Security Access - airside Heavy Rainfall culvert inlet Rain (Frequency) Embankment Heavy Rainfall Two-way radio Ice Storm Cellular Phone Ice Storm Procedures (Inspections/Maintenance) Winter Rain/Rain-on-Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Heavy Snowfall Access to Facility Snow Storm/ Blizzard Access On-site High Wind/ Downburst Access On-site Winter Rain/Rain-on-Snow Access On-site Snow Storm/ Blizzard Two-way radio High Wind/ Downburst

300 Cellular Phone High Wind/ Downburst Security Access - airside Snow Accumulation culvert inlet Snow Accumulation Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Heavy 5 day total Rainfall 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Heavy 5 day total Rainfall 8 12 Emergency Procedures (Flood Level Warning) Freezing Rain 8 12 Access to Facility Ice Storm 8 12 Access On-site Heavy 5 day total Rainfall 8 12 Access On-site Ice Storm culvert inlet Heavy 5 day total Rainfall 8 12 Two-way radio Freezing Rain 8 12 Cellular Phone Freezing Rain 8 12 Personnel (Maintenance/Inspection) Hurricane / Tropical 6 12 Storms Access to Facility Freeze/Thaw 12 6 Access On-site Freeze/Thaw 12 6 Upstream rip-rap Hurricane / Tropical 6 12 Storms Downstream rip-rap Hurricane / Tropical Storms

301 Table 16 FedEx Facility Infrastructure Climate Parameter Existing Risk Future Risk Personnel (Maintenance/Inspection) Hailstorm Dry storage Pond - vegetated Heavy Rainfall Access to Facility Snow Accumulation Access On-site Snow Accumulation Dry storage Pond - vegetated Snow Accumulation Open ditch with gabion Snow Accumulation Outlet structure with Hickenbottom Snow Accumulation Personnel (Maintenance/Inspection) Heavy Snowfall Personnel (Maintenance/Inspection) Lightning Procedures (Inspections/Maintenance) Heavy Snowfall Access to Facility Heavy Snowfall Access On-site Heavy Snowfall Dry storage Pond - vegetated Heavy Snowfall Procedures (Inspections/Maintenance) Rain (Frequency) Emergency Procedures (Flood Level Warning) Rain (Frequency) Access to Facility Heavy Rainfall Access On-site Heavy Rainfall Open ditch with gabion Heavy Rainfall Outlet structure with Hickenbottom Heavy Rainfall Personnel (Maintenance/Inspection) Snow Accumulation Procedures (Inspections/Maintenance) Snow Accumulation Emergency Procedures (Flood Level Warning) Snow Accumulation Equipment for Facility Inspection/Maintenance Snow Accumulation Two-way radio Snow Accumulation Cellular Phone Snow Accumulation Dry storage Pond - vegetated Winter Rain/Rain-on- Snow Two-way radio Lightning Cellular Phone Lightning Personnel (Maintenance/Inspection) Freezing Rain Procedures (Inspections/Maintenance) Freezing Rain Access to Facility Freezing Rain Access On-site Freezing Rain Open ditch with gabion Heavy 5 day total Rainfall Outlet structure with Hickenbottom Heavy 5 day total Rainfall Personnel (Maintenance/Inspection) High Temperature Personnel (Maintenance/Inspection) Heavy Rainfall Procedures (Inspections/Maintenance) Heavy Rainfall Emergency Procedures (Flood Level Warning) Heavy Rainfall Equipment for Facility Inspection/Maintenance Heavy Rainfall Access to Facility Rain (Frequency)

302 Access On-site Rain (Frequency) Security Access - airside Heavy Rainfall Open ditch with gabion Rain (Frequency) Outlet structure with Hickenbottom Rain (Frequency) Personnel (Maintenance/Inspection) Heavy 5 day total Rainfall Procedures (Inspections/Maintenance) Heavy 5 day total Rainfall Dry storage Pond - vegetated Heavy 5 day total Rainfall Two-way radio Ice Storm Cellular Phone Ice Storm Procedures (Inspections/Maintenance) Winter Rain/Rain-on- Snow Procedures (Inspections/Maintenance) Snow Storm/ Blizzard Emergency Procedures (Flood Level Warning) Heavy Snowfall Equipment for Facility Inspection/Maintenance Heavy Snowfall Access to Facility Snow Storm/ Blizzard Access On-site High Wind/ Downburst Access On-site Winter Rain/Rain-on- Snow Access On-site Snow Storm/ Blizzard Open ditch with gabion Winter Rain/Rain-on- Snow Outlet structure with Hickenbottom Winter Rain/Rain-on- Snow Two-way radio High Wind/ Downburst Cellular Phone High Wind/ Downburst Dry storage Pond - vegetated Drought/Dry Periods Personnel (Maintenance/Inspection) Low Temperature 12 8 Personnel (Maintenance/Inspection) Ice Storm 8 12 Procedures (Inspections/Maintenance) Ice Storm 8 12 Emergency Procedures (Flood Level Warning) Heavy 5 day total Rainfall 8 12 Emergency Procedures (Flood Level Warning) Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Low Temperature 12 8 Equipment for Facility Inspection/Maintenance Freezing Rain 8 12 Equipment for Facility Inspection/Maintenance Ice Storm 8 12 Access to Facility Ice Storm 8 12 Access On-site Heavy 5 day total Rainfall 8 12 Access On-site Ice Storm 8 12 Dry storage Pond - vegetated Freezing Rain 8 12 Dry storage Pond - vegetated Ice Storm 8 12 Open ditch with gabion Freezing Rain 8 12 Open ditch with gabion Ice Storm 8 12 Outlet structure with Hickenbottom Freezing Rain 8 12 Two-way radio Freezing Rain

303 Cellular Phone Freezing Rain 8 12 Personnel (Maintenance/Inspection) Hurricane / Tropical Storms 6 12 Access to Facility Freeze/Thaw 12 6 Access On-site Freeze/Thaw 12 6 Open ditch with gabion Extreme Heavy Rainfall 6 12 Outlet structure with Hickenbottom Extreme Heavy Rainfall