Wilket Creek Rehabilitation Project
Toronto and Region Conservation Authority (TRCA), on behalf of the City of Toronto, has initiated a study to assess the geomorphic systems and habitat of the Wilket Creek subwatershed in developing a long-term strategy to address ongoing hazards to municipal lands and infrastructure within Wilket Creek Park as a result of stream erosion.
In accordance with the Environmental Assessment Act, the proposed undertaking is being completed under a Municipal Class Environmental Assessment (Class EA); the prescribed process for projects of this nature. A Master Plan for the water course will be developed thought the Class EA process that will provide recommendations for the long-term stabilization of Wilket Creek.
In addition to the completion of the Class EA, emergency works within Wilket Creek Park are being undertaken as the result of the determination during the initial field investigations that three (3) priority areas were identified within Wilket Creek Park as requiring urgent repairs where erosion has exposed the existing sanitary sewer. Emergency repairs are proposed to be carried out over the next several months at these priority areas, to ensure the protection of municipal infrastructure while the overall strategy is being developed.
The Project Background
The Wilket Creek tributary of the East Don River was one of the watercourses that suffered a significant amount of damage as a result of the August 19, 2005 storm event. The City of Toronto subsequently retained TRCA in 2007 to manage, design and implement large-scale restoration works within Edwards Gardens, and 10 repair projects focused on infrastructure protection and public safety within Wilket Creek Park, to return the park system to a state of good repair.
Shortly following completion of the aforementioned restoration work, another severe storm event hit the Toronto area on June 23, 2008, damaging three of the sites in Wilket Creek Park recently repaired by TRCA. It was evident by this point that a comprehensive study and rehabilitation plan was required to provide long-term protection for municipal infrastructure and public safety within Wilket Creek Park.
In 2009, Toronto Parks, Forestry & Recreation (PF&R) and Toronto Water identified multi-year funding commencing in 2010 for the "Wilket Creek Channel within Wilket Creek Park Rehabilitation Study and Geomorphic Systems and Habitat Study" (the Project) requesting TRCA's assistance to manage the Project on their behalf, including the implementation of any works recommended.
Following an initial assessment by Parish Geomorphic, the consulting firm retained by TRCA to assist with the study and design components of the Project, three areas within Wilket Creek Park were identified as requiring immediate attention due to the risk to municipal infrastructure and/or public safety. These sites are collectively referred to as Site 3, Site 6 and Site 7 by TRCA and the City of Toronto.
Given the anticipated length of time required to complete the study phase, the repair of Sites 3, 6 and 7 were recommended to be expedited for repair as emergency works, with the understanding that the designs for these sites will be in alignment with the overall strategy for Wilket Creek within Wilket Creek Park. TRCA retained Parish Geomorphic Ltd. to draft a design that will address the deficiencies at these locations. In light of the exposed sanitary sewer, Site 6 and Site 7 were addressed first and completed in May of 2012.
Site 3 will be completed in 2 phases. Phase 1 will include all channel works upstream of and including the replacement of the bridge crossing, while Phase 2 will include the sanitary sewer protection and associated channel works downstream.
Planning Mechanism for the Undertaking
The project is following the planning and design process prescribed in the Municipal Class Environmental Assessment (Class EA) for Schedule "B" projects, with the intent of developing a Master Plan for long-term remediation of the entire watercourse.
The Class EA requirements for the development of a Master Plan are as follows:
Phase 1: Definition of the Problem;
Phase 2: Identification and Assessment of Alternative Solutions;
These phases will identify any potential negative and positive effects with the implementation of the project. TRCA will document the decision making process and the value judgments made in selecting the alternative solutions, and will develop a detailed Project Folder upon completion of the study. The Project Folder will be available for review upon request by all interested parties.
The Notice of Study Commencement is available below, and was published in the North York Mirror on June 23, 2011 and June 24, 2011 to inform the local community of the commencement of the Wilket Creek Channel (within Wilket Creek Park) Rehabilitation Study to Address Erosion Hazards Threatening Infrastructure and Geomorphic Systems and Habitat Study, and to advise the public of the mechanisms by which they can participate in the project.
Public and Agency Consultation
The Municipal Class EA process provides that all views be taken into consideration during the planning and design phases of the project. In addition to the development of a comprehensive project contact list comprised of concerned citizens, local interest groups, government agencies and and non-governmental organizations who will receive project information and provide comment as the project progresses, Public Information Centres (Open Houses) will be held to provide detailed information regarding the study, obtain feedback on the evaluation of alternative options and the development of long-term remedial measures, and address any concerns raised regarding the proposed works, and recommended long-term solutions prior to finalizing the study.
If you would like more information about the study, or would like to be added to the Contact List to receive information as the investigation progresses, including notification of Public Information Centres, please contact:
Project Manager, Environmental Engineering Projects
Tel: (416) 392-9690
2012-05-18 Project Update:
Emergency Works Phase II is now complete. The Bata Trail connection from Edwards Gardens to Sunnybrook Park is open to the public effective May 18, 2012.
2012-11-19 Project Update:
TRCA is preparing to begin construction of Phase III of the emergency works within Wilket Creek Park.
Phase 3 will focus efforts on the rehabilitation of the Site 3 location, as identified by TRCA and PF&R during the completion of the August 19, 2005 Storm Damage Project.
The project site is located approximately 400 metres upstream of the washroom buildings and approximately 600 metres downstream of the completed Phase I & II works. This project will be split into two parts with the second portion immediately following the first. The second part of the work will be described in greater detail in a future update. It will be a continuation further downstream from the the first portion.
This site features a 9 metre steel frame bridge with a wooden deck and railings that are in a serious state of disrepair. Rehabilitation of this site has been triggered, in part, due to the low elevation of the current bridge. This allows fallen trees and debris to accumulate easily on the structure threatening the stability of the area.
Upstream of the bridge, the watercourse has migrated towards the valley wall on the right bank and has eroded it to a nearly vertical angle. The length of this eroded section is approximately 40 metres, and there are trees being undercut by the erosion that are leaning and at risk of falling into the creek.
In general, this phase of work involves:
- Moving the channel away from the eroding valley wall (as seen above);
- Widening the channel to reduce erosion;
- Creating a riffle and pool system to improve habitat;
- Installing a new 30 m long freespan bridge to provide safe pedestrian access across the watercourse, and to alleviate the debris jams; and
- Installing protection for the sanitary sewer that crosses the river downstream of the bridge.
During construction there may be interruptions in the trail access through this site. The map below illustrates the proposed construction access route, and construction area.
TRCA will take all precautions necessary to protect public safety by closing trail access during key periods, but will also attempt to minimize disruptions to trail access ass much as possible.
During trail closure periods, park users are asked to bypass the area, via Leslie Street.
2012-12-05 Construction Update:
TRCA staff have installed perimeter fencing around the site and have started to remove trees. This is necessary to access the watercourse to implement the design and install the new bridge. There will be three (3) new trees planted as compensation for every tree removed.
2012-12-17 Construction Update:
The dewatering system has been installed, and water is now being diverted around the work area. Staff are currently excavating the banks and placing stone by the existing bridge to construct the downstream riffle. Once the riffle is completed, the temporary construction crossing will be set up to allow for machinery access on both banks.
2013-01-14 Construction Update:
The downstream riffle has been completed, and the temporary bridge has been installed. Staff are currently in the process of constructing the vegetated buttress that will protect the large erosion scar, as seen in the photograph below.
2013-01-21 Construction Update:
Staff are continuing to place stone and plant materials for the vegetated buttress upstream of the bridge. Bank excavation, shown below, for the upstream riffle has also commenced to provide backfill material for the buttress.
2013-01-28 Construction Update:
Staff are working on the upstream riffle and continuing to work on the vegetated buttress. Willow canes are being planted in between the stone rows as shown in the photo below.
2013-02-06 Construction Update:
The upstream riffle, vegetated buttress, and the pool have all been completed. The picture below shows the snow-covered buttress on the left side, and the newly excavated pool can be seen in the middle of the image by the frozen water. The upstream riffle that was shown on 2013-01-21 has also been finished. Staff will be performing some minor work to finish the downstream riffle and stabilize the bank opposite to the buttress (where staff are standing in the image). Construction of the new bridge is tentatively set to begin around the end of this month.
2013-02-14 Construction Update:
Following completion of the majority of the channel work, staff are begining work on the bridge replacement. As a result, there will be intermittent trail closures in effect for the next 6 to 8 weeks during work hours. During this time, trail users will be unable to cross through the area and will be redirected to Leslie Street.
2013-03-01 Construction Update:
TRCA staff have completed the remainder of the in-water work (see picture below) and have removed the dewatering system. Installation of the new bridge is scheduled to begin within the next two weeks. As a result, there will be intermittent and full trail closures in effect for the next 4 to 6 weeks. The website will be updated once the bridge construction schedule is confirmed.
2013-04-08 Construction Update:
Construction of the new bridge began last week and is expected to be completed by the end of the month. The temporary bridge is still in place to provide public access over the creek, with intermittent closures when equipment and materials require access of this area to complete the remaining works.
Final site restoration activities are also underway, with staff installing straw matting and re-seeding along exposed ground areas, and completing general site clean up work.
2013-05-02 Construction Update:
TRCA's contractors dropped the new bridge into place on April 26th (see photo below). They then began, and almost completed, installation of the concrete panels for the bridge deck. The contractors are now creating the pathway that follows the new bridge alignment. As they finish this process, they will be removing the temporary construction bridge, and this is expected to be completed within the next week.
TRCA's contractors have completed their work. The new bridge is now in place and straw matting, as seen beside the path below, has been installed to reduce the runoff of dirt.Also, shrubs and grass seed have been planted in various areas around the site.