REPORT TITLE: TERM OF COUNCIL PRIORITY NO. 6 - ENHANCE INTEGRITY OF WASTEWATER COLLECTION SYSTEM INCLUDING FLOOD REMEDIATION PROGRAM

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1 J Wokking foh y or REPORT Meeting Date: November 28,2013 Regional Council DATE: October 22,201 3 REPORT TITLE: TERM OF COUNCIL PRIORITY NO. 6 - ENHANCE INTEGRITY OF WASTEWATER COLLECTION SYSTEM INCLUDING FLOOD REMEDIATION PROGRAM FROM: Dan Labrecque, Commissioner of Public Works RECOMMENDATION That the Region of Peel develop a mandatory roof downspout disconnection program for those areas that are connected to the sanitary sewer system with considerations for financial grants or incentives and report to Regional Council in March 2014 or earlier for adoption into the Sewer Use By-law; And further, that a copy of the report of the Commissioner of Public Works, dated October 22,2013, titled "Term of Council Priority No. 6 - Enhance Integrity of Wastewater Collection System including Flood Remediation Program" be forwarded to the Cities of Brampton and Mississauga, the Town of Caledon, Toronto and Region Conservation Authority and Credit Valley Conservation Authority, for information. REPORT HIGHLIGHTS The Wastewater and Stormwater collection systems has seen an impact from intense stormwater inflow and needs to be given special attention due to recent flooding impacts. Recent storm events have highlighted the need for improved response plans, including better defined roles and responsibilities for early action. Approximately 63,000 properties were constructed prior to 1975 and may have their property foundation drains connected to the sanitary system requiring some remedial measures to reduce the number of homes from potentially being flooded. Changes to the building code may also be required in order to modify existing standards to deal more effectively with climate change impacts for future developments.

2 October 22, DISCUSSION I. Background Term of Council Priority (TOCP) No. 6 was initiated as there was a need to enhance the integrity of the Wastewater Collection System. This includes condition assessment of the Region of Peel pumping stations, increased inspections of our wastewater collection system and trunk sewers. The last component of the program was to deal with Inflow and Infiltration (111) which also connects with the flooding issues we are dealing with today. While TOCP No. 4 deals with Storm Water Management, the two programs need to compliment each other in order to expedite the identification of opportunities to reduce current flooding impacts. The Wastewater Collection System in Peel is not a combined system like other municipalities with stormwater designed to enter a combined purpose pipe. In Peel, homes constructed between 1960 and 1975 when storm sewers were not typically available, often allowed the connection of home foundation drains to the sanitary sewer system. In many cases the house roof downspouts were also connected to the foundation drains. Unfortunately foundation drains where never designed to handle the impact of current storm intensities neither were the sanitary laterals and sewers connected to them. Based on the current design of stormwater systems the potential does exist for newer homes also to be surcharged through foundation drains when storm sewers exceed their design capacities and revert to overland flow. This needs to be reviewed in conjunction with work being undertaken with area Municipalities and Conservation Authorities. The Region of Peel's Wastewater collection system has increased its Closed Circuit Television (CCTV) program to look for deficiencies in the collection system and scheduled repairs where necessary. The main trunk sewers have also been through a series of,more complex internal inspections over the past several years with repairs completed or scheduled for capital works. Historically there have been very few back-ups related to structural issues. As identified in the internal audit report of September 16, 2013, the State of Good Repair program was enhanced to increase our assessments of the wastewater pipes. This can be done while replacing aging Wastewater infrastructure, in conjunction with the Water capital program and with area municipality road replacements. Inflow and Infiltration is also a program focus, as there may be some opportunities to upsize the collection system when inflow reduction measures are not sufficient. 2. Action Items to Address Stormwater Flooding Early findings have clearly identified that property foundation drains are one issue related to flooding of residential homes, as are homes that lie within the flood plains. The challenge for Peel is preventing intense rainfall from entering the Wastewater Collection System when the source of the surcharge is the private side foundation drainage system. The following are early actions to address some of those issues. Solutions from area municipalities and Conservation Authorities will also be required to help mitigate the impact of flooding as well. There are approximately 41,000 homes in Mississauga, 20,000 homes in Brampton and 2,000 homes in Caledon for a total of 63,000 homes that were constructed between the periods of 1960 and Regional staff believe the property foundation drains are connected to the sanitary sewer system which also has roof downspouts connected to the foundation drains. Along with other external agencies, Regional staff believe that in many

3 October cases the foundation drains may often surcharged first causing the water to enter the home and eventually surcharging the sanitary sewer system. a) The Region of Peel will be developing a mandatory disconnection program for roof downspouts in these areas and amending the Sewer Use By-law by spring Regional staff are currently reviewing incentive programs for residents who disconnect early and potential penalties for residents that refuse to disconnect. The plan needs to be financially viable so Regional staff will bring back a series of options to Council for discussion before the spring of b) The proposed downspout disconnection program will have to be undertaken with input from area Municipalities as it will result in stormwater being discharged to the surface. Above ground drainage surveys may need to be considered to avoid one neighbour flooding out another. We also need to ensure surface water discharge does not cause undue icing conditions across sidewalks and driveways. In discussions with area municipalities they have indicated this may have an impact on their internal engineering resources related to individual lot grading standards. c) A principle that will be driving the priorities for the Region's collaborative work plan with area Municipalities and Conservation Authorities will be to deal with the areas that have been flooded once or more before expanding remedial measures to other areas which could be impacted in the future. The flooding in Peel is not unique and the Institute for Catastrophic Loss Reduction working with Insurance companies, municipalities and other stakeholders has literature that can help residents and businesses protect their homes from storm sewer and sanitary sewer back-ups and minimize overland flow where possible. This information is readily available and will be used along with other information and provided initially to the first 63,000 homes identified. Additional media information will be put on the Regional, area municipal and conservation authorities respective websites and notifications in Peel's Water and Wastewater billing inserts on how to access those sites to assist in protecting homes and properties. Based on current discussions within the City of Mississauga and Conservation Authorities education and outreach is best lead by one organization to ensure consistent information is provided to the public. Options for this are currently being expored. e) Peel will be continuing to promote the use of sanitary back water valves in the higher risk areas of the collection system. Peel will also continue to identify the additional basement flooding risks that homeowners may cause without the additional process of separating their foundation drains from the sanitary sewer system. As with the proposed downspout disconnection program staff will be looking at the potential for grants or incentives under specific conditions which will be part of the enhanced sewer use downspout disconnection by-law. The household drainage surveys done as a pilot for Cooksville Creek helped residents locate buried plumbing in their basement floors when records no longer existed. This program however has little benefit unless the homeowner went to the next stage by installing back water valves and sump pumps to separate their foundations from the sanitary sewer. To undertake this work for potential 63,000 homes in the future is not financially feasible. It is recommended that when homeowners install back water valves or sump pumps that the plumber doing the work is qualified to undertake the piping investigation and by doing so also takes on the risk that the flood reduction measures are installed correctly and in the proper location. Peel

4 p~h)-o\ -4- October 22,201 3 in turn will no longer be undertaking household drainage surveys in relation to back water valve installations and sump pits. f) To better understand how inflow may be entering the sanitary collection system the Region of Peel over the next two years will be conducting smoke testing in various areas of both the sanitary and storm collection systems. The intent would be to look for cross connections that may exist and to determine by area and in some cases by lot on how the foundation drains are connected to the storm or sanitary sewer systems where records no longer exist. Sanitary collection areas will also be targeted based on current flow monitoring that has identified parts of the system that have higher flows than what they are typically designed for. This work will help confirm the number of homes identified as part of the downspout disconnection program. g) Peel has commenced a program of enhanced sanitary chamber inspections and 1/1 reduction, including water proofing sanitary chamber chimney risers, installation of inflow dishes and water tight chamber covers for infrastructure located in the flood plain. These measures will continue to be applied as needed in areas that have experienced impacts due to overland storm flows and basement flooding. This work is expected to continue into h) Climate change may lead to increased storms with higher frequency and intensity over time. The building code has gone through various iterations over the years. The period from 1960 to 1975 approximately, allowed foundation drains and roof drain spouts to be connected to the sanitary sewer systems. After 1975 the building code separated foundation drains and downspouts from the storm sewer system, and in some cases allowed a third pipe known as Foundation Drain Collectors (FDC). Some municipalities have foundation drains connected to sump pumps where ground water conditions make it viable. Further changes to the current building code may be required for future homes to minimize the risk of flooding in the future, including mandatory backwater valves and requirements for discharging water from foundation drains. i) Emergency Responses to storm events need to be enhanced, clarifying roles and responsibilities for improved collaboration between the Region, area municipalities and Conservation Authorities during these storm emergency situations. This collaboration has commenced and being led by Mississauga Fire with the intent of having a new plan in place for early It has been recommended that Brampton and Caledon, through their respective Fire Chiefs, also be engaged at some point in its development so there is a consistent plan across the Region of Peel. FINANCIAL IMPLICATIONS The cost of additional investigations to better understand how stormwater enters the sanitary sewer system and to implement some remedial measurers is currently built into the Region's 10 years capital program estimated at $5,000,000 per year over the next 10 years. The Cooksville Creek pilot subsidy program to disconnect downspouts, install back water check valve and disconnection of foundation drain by sump pump had a maximum allowance of $6, per house. There were only 22 homes that undertook this incentive before the July flood. If the Region were to expand the incentive area and every home constructed before 1975 took the incentive to the maximum allowable, the cost would be approximately

5 w-~\-5- October 22,2013 $393,750,000. Peel staff will bring forward financial subsidy options for consideration in the Region's Sewer Use By-law update to council in CONCLUSION The Region of Peel working in collaboration with area Municipalities and Conservation Authorities are developing a series of action plans which can reduce flooding risks in the near future while developing larger risk mitigation measures to deal with these intense localized storms. Peel has implemented more detailed testing this Fall and will continue it over the next two years to get a better understanding on how stormwater is actually entering homes and the sanitary collection system. Peel staff are recommending a mandatory downspout disconnection program which is anticipated to be before Regional Council in March of 2014 with some options for grants and incentives including other information for residents looking to protect their homes from potential storm impacts. Residents and businesses will be encouraged to initiate their own flood remediation plans to protect their property which is also being supported by the insurance industry. Dan Labrecque Commissioner of Public Works Approved for Submission: WL D. Szwarc, Chief Administrative Officer For further information regarding this report, please contact Mark Schiller at extension 4394 or via at mark. schiller@pee/region. ca Legislative Services