The Don River and Central Waterfront are among the most degraded waterways in the City of Toronto.

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2 This document was put together following the fourth round of public consultation for the Class Environmental Assessment study for this Project. In June 2011, the Project Team consulted with stakeholders about the alternative design concepts for the preferred solution, the evaluation process that was undertaken, and the preliminary preferred design for the preferred solution. A number of questions were asked frequently. These questions and the related answers are reflected in this document. A more lengthy set of questions and answers can be found in the Public Information Centre #4 report on the Project website, which can be accessed at GENERAL 1. Why is this Project needed? The Don River and Central Waterfront are among the most degraded waterways in the City of Toronto. In 1987, Toronto s waterfront was identified by the International Joint Commission as an Area of Concern in the Great Lakes Basin, due to pollution caused in large part by combined sewer overflows (otherwise known as CSOs). There are 50 CSO outfalls in the study area that discharge a mixture of untreated sewage (18%) and polluted stormwater runoff (82%) directly into the Don River, including Taylor Massey Creek, and the Inner Harbour. Polluted stormwater runoff has been identified as the main contributor to degraded water quality in Toronto in previous studies such as the Toronto and Area Watershed Management Studies on the Don River (1989), various Remedial Action Plan reports and in the Wet Weather Flow Master Plan (WWFMP). The WWFMP was approved by City Council in 2003 and contained recommendations for a system of tunnels, storage and treatment to best address the problem of stormwater and combined sewer overflow discharges to the Don River and Central Waterfront area. The Don River and Central Waterfront Project, a Class Environmental Assessment study, began in 2008 to carry forward the recommendations of the WWFMP to control stormwater and CSO releases, with the goal of improving water quality in the watershed. The Project also addresses dry weather sanitary servicing needs for the existing Don Trunk and Waterfront Interceptor Sanitary Trunk Sewer (STS) systems to service future growth, and provide redundancy (i.e., an alternative sewage route) for the Coxwell Sanitary Trunk Sewer. The potential to integrate wet weather and sanitary sewer system solutions to reduce costs is a key component of the study. 2. What are the benefits of this Project? The implementation of this project will improve both the sanitary trunk sewer system and our environment. Page 2

3 Sanitary Trunk Sewer benefits include: Twinning of the Coxwell Sanitary Trunk Sewer (STS) to provide redundancy and to allow for periodic maintenance and ensure safe, ongoing operation of the Coxwell STS. Upgrading the City's critical Don Sanitary Trunk Sewer system to ensure the system has capacity to effectively service future population growth in the study area. Controlling wet weather flows will achieve the following benefits: Virtually eliminate untreated sewage (from CSOs) from entering the Don River and Central Waterfront through the capture and treatment of flows. This will reduce releases of pathogens and pollutants to waterways, leading to improvements in water quality, enhanced recreational opportunities, and improved aquatic habitat. Help reduce the "flashy" inputs of combined sewer overflows, which contribute to stream erosion and possible flooding. Support revitalization efforts for Toronto's waterfront. Ultimately move us closer to delisting the City of Toronto as a polluted Area of Concern in the Great Lakes Basin. Ensure the City meets Provincial requirements for the control of combined sewer overflows, and support commitments made by Federal and Provincial Governments, for the cleanup of the Areas of Concern through the Canada- Ontario Agreement and Federal Government s commitment through the Bi- National Great Lakes Water Quality Agreement. By bringing together the projected sanitary trunk sewer servicing needs with the wet weather flow control requirements as a complete and integrated system, all of the benefits of the Project will be achieved at a reduced cost. 3. How will this project impact tourism and recreational opportunities along the waterfront? When the proposed system is fully in place, water quality in the Lower Don River and Inner Harbour will be improved, which will support efforts to enhance tourism and recreational opportunities along the central waterfront. 4. How is the study being conducted and what process was used to get to this stage? The Project is being conducted as a Municipal Class Environmental Assessment (EA), Schedule C. There are five phases in the Class EA process. The phases include: Page 3

4 EA Phase What it involves When did/will it happen? Phase 1 Problem or Opportunity Phase 2 Alternative Solutions Phase 3 Alternative Design Concepts Phase 4 Environmental Study Report Phase 5 Implementation Defining the problem or opportunity. Identifying and evaluating alternative solutions to address the problem and establishing the preferred solution. Examining alternative design concepts for the preferred solution and establishing a preferred design concept, as well as identifying measures to minimize any adverse effects. Preparing an Environmental Study Report which summarizes the rationale, planning, design and consultation process for the Project. Implementation of the Project including construction and monitoring. Mid Early 2009 mid 2010 Mid 2011 Fall 2011 To Be Determined pending approvals of Class EA study The preferred solution to resolve the problem of wet weather flow discharges into the Don River and Central Waterfront was recommended in the Wet Weather Flow Master Plan, which was adopted by City Council in In Phase 2 of this Class EA study, the recommended solution in the Wet Weather Flow Master Plan for controlling wet weather flows was carried forward, and further evaluation and analysis was undertaken to identify a preferred solution that addressed both wet weather flow controls and dry weather servicing and capacity issues (which were identified in Phase 1 of the Class EA study) in one integrated manner. In Phase 3 of this Class EA Study, alternative design concepts for the Preferred Solution were considered. This phase focused on identifying preferred sites for various project elements including the offline dry weather and wet weather flow storage tanks, underground vertical storage shafts, tunnel boring machine shafts (i.e. construction shafts), and a wet weather flow treatment facility. Public consultation is an important part of the Class EA process and has taken place throughout all of the phases of this Class EA study. Information on the consultation process and the materials available are provided on the Project's website at: Page 4

5 5. How have the public and other stakeholders been consulted? Throughout the Class EA study process, extensive consultation has taken place with the public, residents' associations, environmental groups, and other stakeholders. Meetings and briefings have also been held with City Councillors, City Agencies, Boards and Commissions and Divisions including Parks, Forestry & Recreation, Transportation, City Planning, the Toronto and Region Conservation Authority (TRCA), Toronto Transit Commission, Public Health, and Waterfront Toronto, among others. Meetings with external review agencies such as the Ministry of the Environment, Ministry of Natural Resources, Department of Fisheries & Oceans, and Environment Canada have also taken place. Finally, First Nations have been engaged through correspondence and meetings during various phases of the study. Consultation and communications activities have included: Four rounds of Public Information Centres (9 open houses in total from 2008 to 2011) and other consultation events (e.g., workshop and public forum in 2010) were held at various stages of the EA study to receive input on the problem/opportunity, the preferred solution, and the preferred design; Individual meetings and briefings with community groups, ratepayers associations, etc.; Project display booths at various locations and events, e.g., local malls, Lake Ontario Evenings hosted by the TRCA; and, Project postcards and newsletters, as well as a project video and website - to raise awareness and provide information to the public. RECOMMENDED SOLUTION AND DESIGN 1. What is the preferred solution and design for the Project? Based on the extensive research and analysis, input from the public, agencies and other stakeholders, the preferred solution and design for the Project has been finalized. The integrated solution addresses wet weather flow controls and sanitary servicing needs in one complete system. The recommended solution and design includes the following components: Sanitary Trunk Sewer System A Lower Don/Coxwell Bypass Tunnel that will be used on a contingency basis as a bypass to the existing Coxwell Sanitary Trunk Sewer (STS) allowing for periodic maintenance and any necessary repairs of the Coxwell STS; Four underground storage tanks for offline storage of peak sanitary flows where additional capacity is needed; and Upgrades to the North Toronto Treatment Plant (NTTP). Page 5

6 Wet Weather Flow Collection and Storage System Three integrated tunnels connected to an equivalent of 15 underground vertical storage shafts (30 metres in diameter) will collect and store combined sewer overflows and convey these flows to a new wet weather flow treatment facility; The three tunnels include the Lower Don Tunnel/Coxwell Bypass (10.9 km); Taylor Massey Creek Tunnel (5.9 km); and Inner Harbour Tunnel (5.6 km); and. Three underground storage tanks for offline storage of combined sewer overflows from 4 remote outfall locations. Treatment of Collected Wet Weather Flow A new wet weather treatment facility will provide high-rate treatment of wet weather flows and will be located on future lakefill in the waterlot south of the Ashbridges Bay Treatment Plant; A new pumping station in Ashbridges Grove Park with forcemains connecting to the new wet weather flow treatment facility; and Upgrade of an existing CSO tank at the North Toronto Treatment Plant. The preferred solution and design (i.e. recommended locations for siting project elements) is shown on the map on page 7. Page 6

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8 SITING OF FACILITIES 1. How were recommended sites identified and finalized in the study? This is an environmental assessment process; each step along the way has narrowed down the options. In Phase 2, a list of candidate sites was identified and narrowed down and in Phase 3, preferred sites and a specific siting location within each site was identified. There are a number of different types of facilities that needed to be sited including: underground storage shafts and tanks, tunnel boring machine construction shafts, underground tunnel routes and connection sites (where existing WWF outfalls will hook into the storage and treatment system) and the WWF treatment site. Possible tunnel routes were identified which were in close proximity to the WWF outfalls that need to be captured. Alternative routes were then evaluated based on a broad set of criteria including technical, social and land use and environmental considerations. Potential sites for locating vertical storage shafts, tunnel boring machine construction shafts, underground storage tanks, were identified based on the following "must have" criteria: 1) site is within close proximity to the tunnels, 2) site is owned by the City or a City-owned entity, and 3) site provides adequate land area for the shaft and construction. A set of screening criteria were then used to short-list sites. Short-listed sites have to have good access to public roads for construction and maintenance purposes, with no or limited potential for adverse environmental impacts. The site must allow for suspension of land use during construction, reinstatement of the land use after construction, and have efficient hydraulic capabilities. Preferred sites were then identified along with the specific recommended location of the facility within each site, giving consideration to technical, social and environmental impacts, and mitigation. To determine the specific location of connections of existing WWF outfalls to the proposed storage system, the following rules of thumb were applied: Where practical, locate the connection close to the outfall (i.e. near the end of the outfall). Reduce/minimize impacts on abutting roads, utilities and services and on future upgraded roads. Where practical, group existing sewers to reduce the number of connections. Input received through public, stakeholder and agency consultation throughout the process and in June 2011 in particular was also important in determining the sites included in the preferred design. Page 8

9 2. Why were sites along the Harbourfront considered for the siting of Project facilities? Fourteen sites were identified as possible sites for locating underground vertical storage shafts in the Inner Harbour West and East (this includes the area east of the Don River to the Ashbridges Bay Treatment Plant). Then, using the process described in the preceding response a preliminary preferred design was identified, including a number of sites in the Central Waterfront. All these sites fulfilled the must have criteria including that they are in close proximity to the proposed wet weather flow tunnel and CSO outfalls which need to be captured, they are on City-owned land, and they are large enough to accommodate the proposed facility. Based on the feedback received during public consultation, and a re-evaluation of the current and planned land uses and social impacts at or adjacent to Little Norway Park, the York Street off ramp, and the Rees Street parking lot, an alternative location for the vertical storage shafts at the Keating Railyard has been recommended in the final preferred design. A temporary tunnel boring machine construction shaft is still being proposed for the Rees Street parking lot to facilitate construction of the Inner Harbour tunnel. 3. Have any changes been made to the preferred design for the Project since the PICs? Yes, a number of changes have been made to the preliminary preferred design presented during the June 2011 consultation events including: - Underground vertical storage shaft at Little Norway Park moved to the Keating Railyard site - Underground vertical storage shaft at York Off Ramp moved to the Keating Railyard site - Underground vertical storage shaft at Rees St. Parking Lot at Queen's Quay has been moved to the Keating Railyard site. Temporary use of the Rees Street site as a tunnel boring machine construction shaft is being recommended. This is required for construction of the Inner Harbour West tunnel. A portion of the site will be disrupted temporarily for a 2 ½ to 3-year duration during construction. Following construction, the site will be restored, with only a small access hatch remaining. Page 9

10 FACILITY IMPACTS 1. Will there be any odours from the underground storage shafts and tanks? How will any odours be controlled? Odours are not expected. We are proposing to utilize carbon based odour control facilities, using proven technology, which will be installed for the new underground storage facilities. In addition, design considerations for the proposed system will include flushing and sediment transport mechanisms to ensure that solids are removed in an efficient and timely manner to further mitigate potential odour concerns. Carbon based filtration systems are currently used at the Western Beaches Storage Tunnel facility and at the Eastern Beaches Storage Tank facilities. The carbon based filters have worked well in controlling odours, which is evident by the lack of odour complaints from local residents. 2. What kind of noise can be expected once the facilities are operational? There will be pumps inside the control building associated with each of the 4 DWF and 3 WWF underground tanks. The pumps will run only following a heavy rainfall event or approximately 40 times per year. There will be a noise baffling system in the pump house so as to minimize any outside noise impacts. 3. What will appear on the surface after the construction of the various project facilities? Vertical Storage Shafts (capturing wet weather flows) Underground vertical storage shafts will be in the order of 30 metres in diameter. The geometry/shape of each underground facility may be unique to a specific site. It is estimated that approximately 75 to 80 per cent of the surface area above the vertical storage shafts can be landscaped or restored while the remaining 20 to 25% would be comprised of at grade vents and access hatches and an odour control housing unit that is approximately 3.7 m wide by 12 m long by 2 m to 3 m tall. Conceptual Image of an Odour Control Unit for an Underground Vertical Storage Shaft Page 10

11 Tunnel Boring Machine Construction Sites The tunnel boring machine requires a shaft diameter of approximately 15 metres to enter and exit from tunnel drilling. After completion of a particular segment of tunnel, the TBM shaft will be capped with an access hatch of approximately 2.0 metres by 2.0 metres in size. The remaining surface area can be restored. Underground Storage Tanks (capturing dry weather and wet weather) Underground storage tank sizes will vary in size depending upon the amount of flow to be captured, ranging from 3,000 cubic metres to 12,000 cubic metres. The above ground control building at each facility housing the mechanical, electrical and odour controls will be approximately 7 metres by 16 metres in size. The area above the tanks can be restored with plantings. Conceptual Image of Underground Storage Tank WWF Connection Sites Following construction at wet weather flow connection sites, there will be maintenance hole access covers and venting with odour control. The access covers will be approximately 0.8 metres by 1.2 metres in size. WWF Pumping Facility There will be a building to house the mechanical, electrical and odour controls. WWF Treatment Facility The footprint of the WWF treatment facility is anticipated to be approximately 8,2000 square metres in size. Page 11

12 Specific information about each site can be found in the Siting and Project Data Book. At the back of each section, artist renderings are included showing what surface structures could look like. These are for discussion purposes and can be viewed at 4. How long will construction take for various project elements? The length of time for construction will vary by project component as follows: - Offline, underground storage tanks: 9-12 months - Underground vertical storage shafts: months - Tunnel Boring Machine shafts: months - Wet Weather Flow Pumping Station: months - Wet Weather Flow Treatment Facility: months - Connection sites: 3-6 months 5. How will the Project facilities impact existing land uses on the recommended sites? The sites selected, along with the specific location of facilities, have been chosen to avoid impact on existing land uses to the greatest extent possible. For example, active use recreational areas have been avoided in the majority of cases. During construction, as with all construction projects, there will be some land use disruption requiring mitigation measures such as temporary rerouting of bicycle paths, pedestrian detours, loss or parking, etc. It is important to note that land use disruption will be temporary and previous land use will be reinstated after construction. 6. How will the facilities impact the natural environment, e.g. trees? With a project of this size, there will be some impacts to the natural environment. Toronto Water is committed to working with local communities, Parks and TRCA during detailed design and construction to minimize impacts on the natural environment, including trees and other vegetation. Mitigation measures will include tree protection zones, and specific siting of facility to minimize the loss of mature trees, among other possible considerations. Where tree removal is required, they will be replaced. Restoration and opportunities for post construction enhancements will be considered in consultation with the local community during detailed design (post EA). Page 12

13 WET WEATHER FLOW TREATMENT FACILITY 1. Where will the treatment facility be located? A new satellite treatment facility to treat captured wet weather flows is being proposed for the waterlot south of the Ashbridges Bay Treatment Plant. 2. Why has the satellite treatment facility been eliminated at Pharmacy Yard? Treatment of the WWF collected and stored in the Taylor-Massey system was previously contemplated at a new treatment facility at the City s Pharmacy Yard. By extending the Taylor-Massey tunnel westerly and connecting it to the Lower Don River tunnel, treatment can now be accomplished at the proposed new treatment facility for wet weather flows to be located in lakefill south of the Ashbridges Bay Treatment Plant. 3. What is the level of treatment proposed? High rate treatment technology is being proposed. This is considered a primary plus level of treatment and will ensure that the City meets all regulatory requirements. Treatment goals for combined sewer overflows (CSOs) are outlined in Ministry of Environment Procedure F-5-5 Determination of Treatment Requirements for Municipal and Private Combined and Partially Separated Sewer Systems. The treatment goal is to provide a treatment level equivalent to primary treatment at a minimum, or 30 percent Carbonaceous Biochemical Oxygen Demand (CBOD) removal and 50 percent Total Suspended Solids (TSS) removal, for an average year during the wet weather season (April to October). The proposed satellite high rate treatment facility will produce a higher quality effluent removing approximately 50% CBOD and 85% TSS. IMPLEMENTATION QUESTIONS 1. When will the project be built? There are a number of steps before the project can be built. First, this study needs to be approved by the Ministry of Environment. Then, preliminary engineering and detailed design will take place for each facility being proposed. Both design and construction are dependent upon City approvals and availability of sufficient funds. Implementation will be phased in over a 25 year timeframe, based on priorities and funding. The initial phases of implementation will focus on twinning of the Coxwell Sanitary Trunk Sewer and meeting minimum Provincial requirements for CSO control. Over the proposed 25-year implementation timeframe for the Project, additional elements would be constructed to provide the dry weather capacity required and to further improve the water quality and environmental benefits Page 13

14 2. What are the next steps in the project? The next steps in the project include: Completing the Environmental Study Report (ESR), Phase 4 of EA process. Seeking approval from City s Public Works and Infrastructure Committee and City Council for submission of ESR to the Ontario Ministry of the Environment. Submitting the ESR to the Ontario Ministry of Environment (MOE) for a 30 day public review period. Seeking all approvals and funding to implement the project. Pending approvals, preliminary and detailed design will be carried out in consultation with impacted local communities. Construction of project components. Some steps may take place simultaneously. Stay in touch. For additional information, visit our website at Send us a letter to: Cleaning Up Our Waterways, 55 John Street, 18 th floor, Metro Hall, Toronto ON M5V 3C6. Send a fax to us at cleanwaterways@toronto.ca or call Information will be distributed via wherever possible. Page 14