City of Pickering. Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report

Transcription

1 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report

2 Environment City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report Prepared by: AECOM Town Centre Boulevard tel Markham, ON, Canada L3R 5Z fax wwwaecomcom Project Number: Date: March, 2013

3 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report Statement of Qualifications and Limitations The attached Report (the Report ) has been prepared by AECOM Canada Ltd ( Consultant ) for the benefit of the client ( Client ) in accordance with the agreement between Consultant and Client, including the scope of work detailed therein (the Agreement ) The information, data, recommendations and conclusions contained in the Report (collectively, the Information ): is subject to the scope, schedule, and other constraints and limitations in the Agreement and the qualifications contained in the Report (the Limitations ); represents Consultant s professional judgement in light of the Limitations and industry standards for the preparation of similar reports; may be based on information provided to Consultant which has not been independently verified; has not been updated since the date of issuance of the Report and its accuracy is limited to the time period and circumstances in which it was collected, processed, made or issued; must be read as a whole and sections thereof should not be read out of such context; was prepared for the specific purposes described in the Report and the Agreement; and in the case of subsurface, environmental or geotechnical conditions, may be based on limited testing and on the assumption that such conditions are uniform and not variable either geographically or over time Consultant shall be entitled to rely upon the accuracy and completeness of information that was provided to it and has no obligation to update such information Consultant accepts no responsibility for any events or circumstances that may have occurred since the date on which the Report was prepared and, in the case of subsurface, environmental or geotechnical conditions, is not responsible for any variability in such conditions, geographically or over time Consultant agrees that the Report represents its professional judgement as described above and that the Information has been prepared for the specific purpose and use described in the Report and the Agreement, but Consultant makes no other representations, or any guarantees or warranties whatsoever, whether express or implied, with respect to the Report, the Information or any part thereof Without in any way limiting the generality of the foregoing, any estimates or opinions regarding probable construction costs or construction schedule provided by Consultant represent Consultant s professional judgement in light of its experience and the knowledge and information available to it at the time of preparation Since Consultant has no control over market or economic conditions, prices for construction labour, equipment or materials or bidding procedures, Consultant, its directors, officers and employees are not able to, nor do they, make any representations, warranties or guarantees whatsoever, whether express or implied, with respect to such estimates or opinions, or their variance from actual construction costs or schedules, and accept no responsibility for any loss or damage arising from or in any way related thereto Persons relying on such estimates or opinions do so at their own risk Except (1) as agreed to in writing by Consultant and Client; (2) as required by-law; or (3) to the extent used by governmental reviewing agencies for the purpose of obtaining permits or approvals, the Report and the Information may be used and relied upon only by Client Consultant accepts no responsibility, and denies any liability whatsoever, to parties other than Client who may obtain access to the Report or the Information for any injury, loss or damage suffered by such parties arising from their use of, reliance upon, or decisions or actions based on the Report or any of the Information ( improper use of the Report ), except to the extent those parties have obtained the prior written consent of Consultant to use and rely upon the Report and the Information Any injury, loss or damages arising from improper use of the Report shall be borne by the party making such use This Statement of Qualifications and Limitations is attached to and forms part of the Report and any use of the Report is subject to the terms hereof AECOM: AECOM Canada Ltd All Rights Reserved 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx

4 AECOM Town Centre Boulevard tel Markham, ON, Canada L3R 5Z fax wwwaecomcom March 22, 2013 Ms Marilee Gadzovski, MSc(Eng), PEng Senior Water Resources & Environmental Engineer Engineering Services Division Community Services Department City of Pickering Pickering Civic Complex One The Esplanade Pickering, ON L1V 6K7 Dear Ms Gadzovski: Project No: Regarding: Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report AECOM is pleased to submit five (5) copies of the Whitevale Master Drainage Plan - Municipal Class Environmental Assessment Report We would like to thank the City of Pickering for their assistance throughout the study We would also like to acknowledge the valuable input received from the Whitevale Storm Water Committee and other interested members of the public Should you have any questions or require further information please do not hesitate to contact the undersigned Sincerely, AECOM Canada Ltd Glenn A Farmer Senior Environmental Technologist glennfarmer@aecomcom GAF:mm Encl 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx

5 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report Distribution List # of Hard Copies PDF Required Association / Company Name 5 1 City of Pickering 1 1 AECOM AECOM Signatures Report Prepared By: Glenn A Farmer Senior Environmental Technologist Blair Shoniker MA, MCIP, RPP Senior Environmental Planner Report Reviewed By: Joseph Puopolo, PEng, PMP Senior Environmental Engineer 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx

6 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report Executive Summary The Hamlet of Whitevale (the Study Area) is located within the valley of West Duffins Creek on Whitevale Road in the City of Pickering and is designated as a Heritage Conservation District Severe rainfall events on July 20 and 23, 2008 passed through the Study Area resulting in flooding along streets and erosion of the approaches to the existing bridge crossing over the West Duffins Creek To address the flooding and erosion issues within the Study Area, the City of Pickering initiated the Whitevale Master Drainage Plan, which is being completed under the Municipal Class Environmental Assessment (MCEA) process, following a Master Plan approach that allows a proponent, such as the City, to carry out the planning, design, and construction of a group of related municipal works together rather than separately on a project-by-project basis The level of assessment followed for the Whitevale Master Drainage Plan will ensure that, at a minimum, Phases 1 and 2 of the MCEA process are satisfied Phase 1 of the MCEA process includes identification and description of the problem A review of available background data and additional field investigations and surveys was completed to gain a thorough understanding of existing conditions within Study Area and to develop the Problem/Opportunity Statement As a result of the current drainage issues within the Study Area, an opportunity exists to improve the storm drainage system which will: Reduce the occurrence of flooding; Mitigate erosion along roadways; Minimize future maintenance requirements; Enhance the quality of surface runoff discharging into the West Duffins Creek; and Improve overall public safety Phase 2 of the MCEA process includes the identification and evaluation of alternative solutions to the problem The first step of Phase 2 was to prepare a description of the Study Area and an inventory of the existing natural, social and economic conditions In order to characterize these conditions, a thorough review of relevant background information was carried out, together with comprehensive field investigations and detailed hydrologic and hydraulic modelling of all elements contributing to the drainage areas A range of alternative drainage improvements were then developed and evaluated to address the problems identified in the following locations: Whitevale Road (East) East of West Duffins Creek Local Residential Roads Intermittent Drainage Feature 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx i

7 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report It should be noted that although the Do Nothing alternative does not address the issues described in the Problem/Opportunity Statement, the EA Act requires its consideration in all Municipal Class EAs as a means of providing a benchmark for evaluating the other alternatives The alternative solutions were comparatively evaluated according to a descriptive or qualitative assessment based on the appropriate criteria developed within the categories of Technical, Natural Environment, Social Environment, Cultural Environment and Financial representing the broad definition of the environment described in the Ontario Environmental Assessment Act (OEAA) Following public and agency engagement the recommended Master Drainage Plan was determined This Plan consists of a combination of improvement measures to address flooding, erosion and water quality issues that will ensure adequate protection for the local residents within the Study Area The elements of the Master Drainage Plan and the associated MCEA schedules include the following: Whitevale Road (East) - Alternative # 2 Rural Reconstruction Schedule A+; Local Residential Roads Alternative # 2 Local Road Improvements Schedule A; Intermittent Drainage Feature Alternative # 5 Storm Flow Diversion to Whitevale Road Storm Sewer Schedule A+; and Additional Surface Drainage and Erosion Improvements at Whitevale Road (West) and North Road Schedule A As part of implementing this project, mitigation and monitoring measures have been recommended to ensure protection and enhancement of natural environment, social environment and cultural environment features Also additional considerations associated with project implementation have been identified as follows: Permits & Approvals; Additional Studies; Construction Phasing & Integration; Weather Conditions; Detailed Design Considerations; and Additional Public Consultation The Whitevale Master Drainage Plan has been completed to satisfy the requirements of the Ministry of the Environment (MOE) Municipal Class Environmental Assessment process, including public and regulatory agency consultation Public consultation included notifications (Notice of Commencement and Notice of Completion), two Public Information Centres (PICs), and two Citizen Liaison Committee Meetings All of the preferred solutions identified as elements of the Master Plan fall within Schedule A/A+ undertakings and can therefore proceed directly to detailed design and / or construction For projects identified as Schedule A+, public notification is required prior to implementation 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx ii

8 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report Table of Contents Statement of Qualifications and Limitations Letter of Transmittal Distribution List Executive Summary 1 Introduction 1 11 Background 1 12 Overview of the Municipal Class Environmental Assessment (MCEA) Planning Process Project Classifications Master Plan Process Public and Agency Consultation 6 2 Phase 1 Identification & Description of the Problem 7 21 Definition of the Master Plan Study Area 7 22 Identification of the Problem 7 23 Problem/Opportunity Statement 7 3 Phase 2 Identification & Evaluation of Alternative Solutions to the Problem 8 31 General 8 32 Description of the Study Area 8 33 Summary of Available Background Information Background Data Collection and Review Field Investigations 9 34 Study Area Physical Characteristics Climate Surficial Soils Land Use Archaeological & Heritage Resources Environmental Features & Natural Hazards Environmental Features Natural Hazards Surface Drainage Existing Storm Drainage Capacity Assessment Study Area Peak Flow Estimates Intermittent Drainage Feature Hydraulic Capacity Assessment Whitevale Road Storm Drainage Capacity Assessment Field Survey & CCTV Visual Inspection Sewer Design Capacity Hydraulic Grade Line (HGL) Assessment 15 4 Identification and Description of Alternative Solutions Whitevale Road (East) Alternative #1 - Do Nothing Alternative #2 Rural Reconstruction Alternative #3 Urban Reconstruction Local Residential Roads Alternative #1 - Do nothing 18 page 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx

9 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report 4122 Alternative #2 Local Road Improvements Alternative #3 Rural Reconstruction Alternative #4 Urban Reconstruction Intermittent Drainage Feature Alternative #1 - Do nothing Alternative #2 Downstream Channel Improvements Alternative #3 Upstream Storage Pond Alternative #4 Storm Flow By-Pass Sewer Alternative #5 Storm Flow Diversion to Whitevale Road Storm Sewer Evaluation of Alternative Solutions Description of the Evaluation Methodology Application of the Evaluation Methodology Components of the Selected Alternative Solution 20 5 Public Consultation Public and Agency Consultation during Phase Notification of Project Commencement and Invitation for Comments Comments Received and Their Consideration in the Project Notification of Public Information Centre (PIC) # Public Information Centre (PIC) # Comments Received During PIC #1 and Their Consideration in the Project Notification of Public Information Centre (PIC) # Public Information Centre (PIC) # Comments Received During PIC #2 and Their Consideration in the Project Citizen Liaison Committee Meetings Citizen Liaison Committee Meeting # Citizen Liaison Committee Meeting # Description, Implementation and Monitoring of the Master Drainage Plan Elements of the Master Plan Whitevale Road (East) - Alternative # 2 Rural Reconstruction Local Residential Roads Alternative # 2 Local Road Improvements Intermittent Drainage Feature Alternative # 5 Storm Flow Diversion to Whitevale Road Storm Sewer Additional Surface Drainage & Erosion Improvements Whitevale Road (West) North Road Implementation Considerations Estimated Master Plan Component Costs Summary of the Potential Effects and Recommended Mitigation Measures Notification of Project Completion Timeframe for Implementation 32 7 Summary 33 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx

10 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report List of Figures Figure 1 Study Area 2 Figure 2 Overview of the Municipal Class EA Process 5 Figure 3 Existing Surficial Soils Back of Report Figure 4 Existing Land Use Back of Report Figure 5 Existing Environmental Features & Natural Hazards Back of Report Figure 6 Existing Drainage Infrastructure Back of Report Figure 7 Existing Surface Drainage Conditions Back of Report Figure 8 Existing Surface Drainage Conditions North Back of Report Figure 9 Existing Condition 100-Year Floodplain Delineation Back of Report Figure 10 Whitevale Road (East) Storm Sewer Drainage SystemBack of Report Figure 11 Whitevale Road (West) Storm Sewer Drainage SystemBack of Report List of Tables Table 4-1: Components of the Preferred Solution 21 Table 5-1: Comments and Responses PIC #1 24 Table 5-2: Comments and Responses PIC #2 26 Table 6-1: Summary of Estimated Master Plan Component Costs 29 Table 6-2: Mitigation and Monitoring Measures 31 Appendices Appendix A Appendix B Appendix C Appendix D Appendix E Appendix F Appendix G Background Data Sources Field Investigations Stage 1 Archaeology Report Hydrologic Information Hydraulic Information Alternatives Evaluation & Preferred Solutions Public Consultation 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx

11 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report 1 Introduction 11 Background The Hamlet of Whitevale (the Study Area) is located within the valley of West Duffins Creek on Whitevale Road in the City of Pickering and is designated as a Heritage Conservation District (refer to Figure 1) In July 2008, severe rainfall events (July 20 and 23, 2008) that passed through the Study Area resulted in flooding along streets and erosion of the approaches to the existing bridge crossing over the West Duffins Creek Following this event, the City of Pickering retained AECOM Canada Ltd to carry out an emergency inspection of the bridge which confirmed significant erosion damage along the approach embankments caused by surface runoff from the surrounding lands as well as damage/blockage of the existing storm sewer outfall adjacent to the bridge crossing In addition, significant quantities of sand and gravel had been deposited into the watercourse as a result of flooding and erosion along local roads In order to address the existing flooding and erosion issues within the Study Area, the City of Pickering initiated the Whitevale Master Drainage Plan, which is being completed under the Municipal Class Environmental Assessment (MCEA) process Specific objectives of this Study are to: Collect available background data and carry out additional field investigations and site surveys in order to gain a thorough understanding of existing conditions within Study Area; Develop and evaluate a range of alternative drainage improvements, including source, conveyance and end-of-pipe measures, structural works, management practices and policies that can be applied to address identified problems; Identify additional stormwater retrofit measures that can be incorporated into the existing development to address both stormwater quality treatment and flow control; Ensure that all solutions achieve adequate protection for the local residents within the Study Area; and, Satisfy the requirements of the Ministry of the Environment (MOE) Municipal Class Environmental Assessment process, including public and regulatory agency consultation 12 Overview of the Municipal Class Environmental Assessment (MCEA) Planning Process As required under the Ontario Environmental Assessment Act (OEAA), the Study followed the MCEA planning process, as prescribed by the Municipal Engineers Association (MEA) Class EA document - October, 2000 as amended in 2007 & 2011 The MCEA process allows the City to satisfy the requirements of the EA Act for municipal infrastructure without having to either undertake an Individual EA or request a specific exemption for the project Municipal projects addressed by the MCEA may be implemented without further approval under the OEAA, provided that the approved MCEA planning process is carried out The stated purpose of the OEEA is to provide for the betterment of the people of the whole or any part of Ontario by providing for the protection, conservation and wise management in Ontario of the environment, where the broad environment includes the natural, social, cultural, built, and economic environments The provisions of the OEEA require municipalities to carry out an environmental assessment for public works projects, including those undertaken for municipal roads, water and wastewater systems, and transit ventures that are subject to the MCEA As described in the MEA Class EA document, this process is a five phased decisionmaking framework for the planning and design of municipal infrastructure 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx 1

12 Concession 7 Road Pickering Whitby Sideline 22 Road Sideline 28 Road Sideline 26 Road Urfe C Sideline 32 Road Country Lane North Road Markham Ajax Toronto Area of Close-up Lake Ontario N Sideline 24 Road () 7 () 7 City of Pickering Whitevale Road Golf Club Road N Sideline 26 Road Altona Road Town of Markham Concession 4 Road York+Durham Line Petticoat Creek th Avenue Concession 4 Road West Duffins Creek Map Document: (P:\ \000-CADD\050 GIS WIP\MXDs\WorkingMXDs\ KeyMapmxd) 11/10/ :54:06 PM Concession Road 11 White's Road Little Rouge River Concession 3 Road Rosebank Road Basemapping from Ontario Ministry of Natural Resources Whitevale Master Drainage Plan ² m ,000 1:36,000 UTM Zone 17N, NAD 83 Legend Waterbody Cartographic Wetland Intermittent Stream Permanent Stream Railway Study Area May 2012 Project Figure 1

13 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report The key principles of the MCEA process include: Consultation with affected parties upon commencement, and throughout the process, of the project; Consideration of a reasonable range of alternatives, including both the functionally different alternatives to and the alternative methods of implementing the preferred solution; Identification and consideration of the effects of each alternative solution and/or method on all aspects of the environment (ie, natural, cultural, social, economic, etc); Systematic evaluation of all alternative solutions and/or methods in terms of the advantages and disadvantages associated with each to determine the net environmental effects; and Provision of clear and complete documentation of the planning process followed, to ensure transparency and traceability of the decision-making process followed for the project 121 Project Classifications The MEA Class EA document classifies projects into four separate categories depending on the potential environmental effects and significance: Schedule A, A+, B, and C undertakings The level of review associated with each category to satisfy the MCEA requirements, and thereby achieve compliance with the EA Act, is described below Schedule A/A+ This category includes projects that are limited in scale, have minimal environmental impacts and include a number of municipal maintenance and operational activities These undertakings are approved and may proceed directly to Phase 5 for implementation without completing the other phases As part of the 2007 amendments to the MCEA process, the Schedule A+ classification was introduced to supplement the requirements of Schedule A undertakings, which includes projects that are pre-approved; however, the public must be notified prior to project implementation (ie, Phase 5) Schedule B These projects have the potential for some adverse environmental effects and, therefore, the municipality is required to undertake a screening process (ie, Phases 1 and 2) involving mandatory contact with directly affected public and relevant agencies to ensure that they are aware of the project and that their concerns are addressed In addition, it is required that a document must be prepared and submitted for review by the public and review agencies for these undertakings If there are no outstanding concerns, the municipality may proceed to Phase 5 for implementation Schedule C Projects included under this classification have the potential for significant environmental effects and must proceed under the full planning and documentation procedures specified in the MEA Class EA document (ie, Phases 1 to 4) An Environmental Study Report must be prepared and submitted for review by the public and relevant agencies for these undertakings If there are no outstanding concerns, the municipality may proceed to Phase 5 for implementation 122 Master Plan Process The MEA Class EA document includes a Master Plan process that allows a proponent, such as the City, to carry out the planning, design, and construction of a group of related municipal works together rather than separately on a project-by-project basis, thus providing the following benefits: The rationale for the individual projects is better defined; The infrastructure alternatives are more broadly established; 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx 3

14 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report The extent of potential effects are better understood; The ability to integrate land use planning; and The ability to assess decisions from a variety of perspectives The Master Planning process differs from project specific undertakings in several aspects, and facilitates long range planning that enables the municipality to identify opportunities and proactively develop strategies for addressing any associated issues This approach generally yields a series of individual activities, projects, and programs, together with a phased implementation plan that covers an extended time period Accordingly, the works may be implemented separately as individual projects but, collectively, they form part of the overall management system embodied in the Master Plan An outcome of the Master Planning process is the identification of individual projects as Schedule A, A+, B, or C undertakings, based on their level of complexity and potential effects on the environment The level of assessment followed for the Whitevale Master Drainage Plan will ensure that, at a minimum, Phases 1 and 2 of the MCEA process are satisfied The resulting storm drainage improvement strategy will consider a reasonable range of alternatives to address deficiencies in the drainage system and identify potential solutions to reduce the risk of flooding of roadways and properties, reduce surface erosion and, where possible, enhance the quality of stormwater runoff discharged into the West Duffins Creek The Study is being undertaken in accordance with Approach #2, as described in Appendix 4 of the MEA Class EA document This approach involves the preparation of a Master Plan document at the conclusion of Phases 1 and 2 of the MCEA process where the level of investigation, consultation and documentation are sufficient to fulfill the requirements for Schedule B projects Any Schedule C undertakings identified in the Master Plan document will require the completion of Phases 3 and 4 of the MCEA prior to the implementation of the proposed works An overview of the MCEA process is shown on Figure 2, which provided the framework for the current Study, and the following provides a description of the phases that will be completed for the Whitevale Master Drainage Plan Phase 1: Identify the Problem / Opportunity This phase involves not only identifying the problem/opportunity, but also describing it in sufficient detail to lead to a clear problem/opportunity statement As part of describing the problem/opportunity, input from review agencies and the public can be solicited Phase 2: Identify and Evaluate Alternative Solutions to the Problem / Opportunity This phase involves the following six steps: Prepare a general inventory of the existing natural, social and economic environments in which the project is to occur; Identify all reasonable alternative solutions to the problem / opportunity; Identify the net positive and negative effects of each alternative solution including mitigating measures; Evaluate the alternative solutions; Consult with review agencies and the public to solicit comment and input; and Select or confirm the recommended solution(s) 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx 4

15 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report Figure 2 Overview of the Municipal Class EA Process PHASE 1 Identify Identify & Describe Describe the the Problem Problem Public Information Forum # 1 May 20, 2009 Schedule A, B A, & A C +, B Projects & C Schedule A/A + Project PHASE 2 Evaluate Alternative Solutions & Establish the Preferred Solution Public Information Forum # 2 March 11, 2010 Schedule B B Project Schedule C C Project PHASE 3 Identify Alternative Design Concepts, Potential Environmental Effects and the Preferred Concept PHASE 4 Prepare Environmental Study Report Documenting Phases 1-3 Discretionary Review Agency / Public Consultation Discretionary Review Agency / Public Consultation File Master Plan Document Mandatory Review Agency / Public Consultation Opportunity for Part II Order 30 CALENDAR DAY PUBLIC REVIEW PERIOD IMPLEMENTATION OF THE PROJECTS THAT MAKE UP THE MASTER PLAN Note: The MCEA process followed for the current study is highlighted in blue 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx 5

16 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report Following completion of Phase 2, documentation of the initial two phases must be prepared and placed on public record for a period of at least 30 calendar days to provide review agencies and the public with an opportunity to review these materials During this review period, concerned individuals have an opportunity to request a Part II Order under the OEAA for proposed works identified as either Schedule B or C undertakings before the project may proceed to implementation A Part II Order requires that an Individual EA be carried out, documented, and submitted to the Minister of the Environment for review and approval The decision on whether the project should be subject to a Part II Order rests with the Minister In addition, the Minister may deny the Part II Order, but attach a condition to the denial requiring the proponent to undertake the Project as a Schedule C rather than a Schedule B under the MCEA process Once the public review period has expired and there are no outstanding Part II Order requests (for Schedule B and C projects), the municipality may proceed to the final phase of the planning and design process Phase 5: Complete Contract Drawings and Documents and Proceed to Construct, Operate, and Monitor the Project This phase involves completing contract drawings and tender documents, incorporating the recommended solution and mitigating measures identified during the previous phases of the process Once contracts are awarded, construction can take place and the project is implemented Any monitoring programs identified during the MCEA process shall be undertaken to ensure that the environmental provisions and commitments made during the process are fulfilled and effective 123 Public and Agency Consultation As required under the MCEA process, consultation with the public and government review agencies is necessary throughout the project The purpose of the consultation process is to inform stakeholders of the project details and give all interested parties an opportunity to provide input or comments related to the undertaking A description of the consultation activities carried out during Phases 1 and 2 of the Whitevale Master Drainage Plan are presented in Section 2 and 5 of the report 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx 6

17 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report 2 Phase 1 Identification & Description of the Problem 21 Definition of the Master Plan Study Area The area under consideration for this Study is the Hamlet of Whitevale (the Study Area), located within the valley of West Duffins Creek on Whitevale Road in the City of Pickering and is designated as a Heritage Conservation District The Study Area comprises a total area of 373 ha (Figure 1) For the purpose of the hydrologic analyses and related investigations undertaken as part of the existing conditions assessment, the Study Area has been expanded to include the catchment areas that contribute to the West Duffins Creek within the Study Area, as shown on subsequent report figures The hydrologic Study Area covers an area of approximately 95 ha, which is dominated by a mixture of agricultural lands, forested valley land and large residential properties that have not changed significantly in character since the late 19th century 22 Identification of the Problem In July 2008, severe rainfall events (July 20 th and 23 rd ) that passed through the Study Area resulted in flooding along streets, several properties and erosion of the approaches to the historic Whitevale bridge crossing over the West Duffins Creek The City of Pickering retained AECOM Canada Ltd to carry out an emergency inspection of the bridge that confirmed significant erosion damage along the approach embankments caused by surface runoff from the surrounding lands as well as damage/blockage of the existing culvert adjacent to the bridge crossing In addition, significant quantities of sand and gravel had been deposited into the watercourse as a result of erosion of local roadside shoulders Excess runoff generated from the surrounding lands also resulted in localized flooding and subsequent damage to private property 23 Problem/Opportunity Statement As a result of the current drainage issues within the Study Area, an opportunity exists to improve the storm drainage system which will: Reduce the occurrence of flooding; Mitigate erosion along roadways; Minimize future maintenance requirements; Enhance the quality of surface runoff discharging into the West Duffins Creek; and Improve overall public safety 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx 7

18 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report 3 Phase 2 Identification & Evaluation of Alternative Solutions to the Problem 31 General Given that the Study is following the MCEA process for a Master Plan (Approach # 2) and there was the potential that the plan would consist of a variety of Schedule A, B and C undertakings, the first step of Phase 2 was to prepare a description of the Study Area and an inventory of the existing natural, social and economic conditions In order to characterize these conditions, a thorough review of relevant background information was carried out, together with comprehensive field investigations and detailed hydrologic and hydraulic modelling of all elements contributing to the drainage areas 32 Description of the Study Area Following the identification of the problem and opportunities established for the Study, an assessment of existing environmental conditions was undertaken The purpose of this step in the MCEA process is to establish an inventory of the natural, social and economic environments within the Study Area, which are to be considered when determining the potential effects that could result from the implementation of each of the alternative solutions The existing conditions assessment included a comprehensive review of available background information, together with the results of specific field investigations to fill any data gaps identified A summary of the secondary source information reviewed and the field reconnaissance carried out is provided below 33 Summary of Available Background Information 331 Background Data Collection and Review In order to characterize existing Study Area conditions, available background data was collected from various sources including the City of Pickering, Toronto and Region Conservation Authority (TRCA) and other government agencies as well as local residents Key background data sources utilized as part of the existing conditions characterization included the following: Background Study Reports including: Whitevale Report (Operations & Emergency Service, City of Pickering, July 2008); Summary of Whitevale Drainage issues and mapping (Whitevale Stormwater Committee, September 2008); Previous road re-construction and major repair information as well as Operations & Maintenance reports carried out within the Study Area from the City of Pickering; City of Pickering Stormwater Management Guidelines; Environment Canada s Climate Normals ( ) as well as local rainfall data (ie, July, 2008); City of Pickering Official Plan; Hamlet of Whitevale Heritage Conservation District Study Background Report (1989), District Plan and District Guide (1990); and, Other watershed/subwatershed studies and stormwater management reports completed within or adjacent to the Study Area (eg, Duffins & Carruther s Creek Watershed Report, Seaton MESP (draft), local road improvement studies and Class EAs - Whitevale Road Bridge, etc); 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx 8

19 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report Available Mapping, Modelling & GIS Data: Existing floodplain mapping, FVS/FVR locations, documented erosion sites and hydraulic modelling available from TRCA (ie, HEC-RAS model for Duffins Creek Watershed); Natural heritage features (ie, wetlands, terrestrial, vegetation and aquatic biology) and information available from TRCA s Regional Monitoring Network (RMN); Topographic mapping (digital DEM), 2008 orthophotography, Teranet property fabric and survey monument data from the City of Pickering; Recreational use information including existing and planned trail networks and linkages from the City of Pickering and TRCA; and Soil Survey of Ontario County Soils (Olding, AB, RE Wicklund and NR Richards, 1956) A complete list of background data sources is also included in Appendix A 332 Field Investigations Following the collection, review, and compilation of the above-noted background documentation, a number of field investigations were carried out to verify background information and fill any identified data gaps Primary activities included the following: Field observations and verification relating to existing land uses, drainage patterns, topographic boundaries, existing storm drainage deficiencies, areas of surface erosion (ie, swales, sewers, roads, culvert inlet/outlets etc) and identification of notable vegetation located within road allowances; Preparation of a detailed photo log (May 2011) depicting existing drainage system components; Geodetic survey to confirm the location, type, size, elevation and general condition of the existing storm drainage system on Whitevale Road (February 2011) including; ditch inlets; catch basins; manholes; storm sewer sizes and inverts; and Road and ditch cross-sections (including local roads) Geodetic survey of the existing intermittent drainage feature extending from North Road to Mill Street (February 2011) including: low flow channel dimensions; channel cross-sections; culvert crossing details; and location and elevation of adjacent structures CCTV inspection of approximately 400 m of existing storm sewer system on Whitevale Road (October 2011) Stage 1 archaeological assessment (May 2011) Additional field photos, survey data and CCTV inspection details are included in Appendix A 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx 9

20 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report 34 Study Area Physical Characteristics 341 Climate Meteorological data obtained from the nearest long-term climate stations (Greenwood MTRCA & Toronto) confirm a total average annual precipitation of just over 800 mm, with approximately 130 cm comprising snow and just over 700 mm falling as rain Average monthly air temperature ranges from approximately -4C in January to over 22C in July 342 Surficial Soils The Study Area is situated within a large till plain area associated with the South Slope physiographic region (Chapman & Putman) Surficial soils within the upland portions of the Study Area (refer to Figure 3) are comprised of soils from the Woburn and Milliken series (Soil Survey of Ontario County Soils, Report 23 of the Ontario Soil Survey) These loam type soils originate from medium textured tills and are typically found in areas with moderate to gentle slopes The soils are suitable for growing a wide variety of crops including hays and grains The internal/external drainage characteristics for the Woburn and Milliken soil series ranges from well drained to imperfectly drained with equivalent Hydrologic Soil Group (HSG) ratings of B and BC respectively (Chart H2-6A, MTC Drainage Manual Volume ) Surficial soils found within the valley land area associated with West Duffins Creek are classified as Bottomland This soil series is comprised of alluvial deposits that vary in texture and maintain an equivalent HSG value of BC 343 Land Use The Study Area (ie, Hamlet of Whitevale) is designated as a Rural Hamlet in the City of Pickering Official Plan and is bisected in an east west direction by Whitevale Road (ie, 5 th Concession Road beyond the Hamlet boundary) which comprises a paved, two lane local road (refer to Figure 4) Whitevale Road maintains a rural cross-section through a majority of the Study Area and maintains a pavement width ranging from 55 m to 7 m and right-of-way (ROW) width of 20 m Notable north-south roads extending from Whitevale Road include Altona Road at the west limit of the Study Area and North Road to the east Smaller local roads within the Study Area (ie, Mill, Gladstone, Churchwin, Factory and Byron Streets) are unpaved and maintain a rural cross-section with travelled widths ranging from 4 m to 6 m and ROW widths ranging from 10 m to 15 m An assessment of existing land use and impervious cover within the Study Area was completed using available highresolution orthophotography (2008) with additional verification during subsequent site visits in January and May of 2011 As shown on Figure 4, a majority of the impervious cover within the Study Area is associated with existing rural residential land uses adjacent to Whitevale Road both east and west of the West Duffins Creek valley The West Duffins Creek bisects the Study Area and consists primarily of forested cover associated with the valley lands Land uses within the larger hydrologic Study Area surrounding the Hamlet are considered rural in nature and include agricultural uses (ie, east of North Road and west of Altona Road) and open pasture / regeneration areas (ie, west of North Road and Golf Club Road) 344 Archaeological & Heritage Resources A Stage 1 archaeological assessment was undertaken for Study Area as part of the Whitevale Master Drainage Plan by Advance Archaeology A copy of this report is provided as Appendix C to this report The archaeological Study Area was scoped to include only the property located within existing road allowances within the Study Area (ie, Hamlet of Whitevale) due to property access constraints 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx 10

21 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report Available background data was obtained from the Ontario Ministry of Tourism and Culture s archaeological site database which revealed no known archaeological sites within the current Study Area boundaries as described above However, there are nineteen (19) recorded sites within a 1 km radius which include: Two (2) known sites and a possible third location within the boundaries of the Hamlet (beyond existing road allowances); Five (5) sites within 500 m of the Hamlet boundary; and, Twelve (12) additional sites between 500 m and 1 km including seven (7) findspots of single artifacts, three (3) larger aboriginal sites and two (2) Euro Canadian homesteads A field investigation (windshield and foot) was carried out May 2011 to verify existing conditions Results revealed that a majority of the Study Area has been previously disturbed through the following activities: Sewer, sidewalk road and driveway construction and repair; Placement of fill for road approaches associated with the Whitevale bridge; and Landscaping, planting/removal of trees along boulevards Accordingly, most of the Study Area is deemed to have a low archaeological potential Notwithstanding, there are several small areas within the Study Area that remain undisturbed (ie, within existing road allowances and / or boulevards) which could have moderate to high archaeological potential given the presence of existing documented sites in the immediate vicinity, proximity to a historic watercourse of significance and fact that the Hamlet of Whitevale is designated Heritage Conservation District Approximately eleven (11) local areas have been identified that will require a Stage 2 archaeological investigation (test pit method) should a selected storm drainage solution(s) be proposed within or in close proximity to the sites Locations are identified in Appendix B and include: Six (6) along Whitevale Road One (1) SE corner Whitevale Road and Factory Street One (1) NE corner Whitevale Road and Gladstone One (1) Gladstone Street Two (2) Churchwin Street 345 Environmental Features & Natural Hazards 3451 Environmental Features Existing environmental feature mapping within and adjacent to the Study Area was obtained from available background data including TRCA databases and mapping, City of Pickering OP schedules and additional field reconnaissance As shown on Figure 5, the most predominant environmental feature within the Study Area is the existing Whitevale Corridor The Whitevale Corridor is designated as an Environmentally Sensitive Area (ESA) and generally comprises the West Duffins Creek corridor, through the central portion of the Hamlet TRCA s targeted Terrestrial Natural Heritage System (TNHS) has also been delineated on Figure 5 and includes existing environmental features as well as potential restoration areas (eg, wetlands, succession, forest, etc) The targeted TNHS extends beyond the existing ESA boundary and includes open space areas within residential properties located south of Whitevale Road on both the east and west sides of West Duffins Creek However, no significant environmental features of TNHS boundaries are noted within the northeast quadrant of the Study Area 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx 11

22 City of Pickering Whitevale Master Drainage Plan Municipal Class Environmental Assessment Report Additional field reconnaissance was also completed to identify notable vegetation (ie, trees etc) within the Study Area road allowances Figure 5 confirms approximately twenty-five (25) to thirty (30) medium to large diameter trees located along Whitevale Road, five (5) to six (6) along the east side of North Road, including a potential Butternut tree located north of Churchwin Street Significant areas of vegetation were also noted along portions of Whitevale Road, Mill Street and Churchwin Street Several of these locations on Whitevale Road (refer to Figure 5) also include steep side slopes that will require additional consideration when evaluating potential storm drainage solutions 3452 Natural Hazards Available flood line and regulation mapping was obtained from TRCA and has been included on Figure 5 The extent of existing flooding confirms that two (2) structures, located immediately east of West Duffins Creek, would be subject to flooding under the Regulatory Storm Event (Hurricane Hazel) A number of additional properties along both the east and west side of West Duffins Creek are also located within TRCA s regulation limit There are no additional natural hazards identified within the remaining Study Area, beyond the West Duffins Creek valley 346 Surface Drainage Surface drainage within the Study Area is generally conveyed in an east and west direction towards West Duffins Creek through a network of intermittent swales and roadside ditches and culverts and is discharged to West Duffins Creek at a number of minor outlet locations along West Duffins Creek Storm runoff from local side streets and adjacent properties generally outlet to Whitevale Road which comprises a paved two-lane rural road cross-section with sections of roadside ditches and cross culverts as well as sections of storm sewer and ditch inlets that ultimately outlet into West Duffins Creek near the existing bridge crossing (refer to Figure 6) Some segments of Whitevale Road comprise ill-defined ditches with little or no capacity to convey surface runoff, and in some cases have been altered by private property owners from the original design and function Other sections of road edge and road base material along Whitevale Road also appear to be cracking and eroding, as a result of significant runoff and excessive velocities In addition to the existing minor system drainage system on Whitevale Road, storm runoff from the lands to the north and northeast are intercepted by an existing intermittent drainage features that originates along North Road and extends through the rear of several properties, crossing North Road, Churchwin, Gladstone and Mill Street prior to discharging northwest of the Study Area into West Duffins Creek near the former Whitevale Dam Development in the Hamlet of Whitevale subwatershed within the City of Pickering (City) occurred prior to the adoption of current stormwater management (SWM) practices The limited incorporation of effective SWM measures, whether lot level, conveyance or end-of-pipe controls, has contributed to localized flooding, surface erosion and impaired water quality 35 Existing Storm Drainage Capacity Assessment In order to confirm the hydrologic and hydraulic capacity of the existing storm drainage system within the Study Area, additional detailed analyses were undertaken to: Determine return period peak flows at key locations within the Study Area; Confirm the hydraulic capacity of the intermittent drainage feature including culvert crossings, determine the extent of existing flooding and identify existing flood susceptible structures; and Confirm the hydraulic capacity (ie, full flow and Hydraulic Grade Line HGL) of the existing storm sewer system located along the east and west portions of Whitevale Road 04ra_ _Whitevalemdp-MCEA Final Rpt_ Docx 12