The City of Toronto has completed an Addendum to update the 2011 Scarborough Waterfront CSO and Stormwater Outfalls Control Class Environmental Assessment (EA) and Flood Protection Study. The Addendum identifies solutions to reduce the risk of future flooding, address combined sewer overflow control and water quality.
Following consultation, the recommendations are:
The study area is bound by Victoria Park in the west and Brimley Road in the east and located between the CN Rail in the north, and Lake Ontario shoreline in the south. This area is served by a mixture of combined, partially separated storm and sanitary sewers. There are six combined sewer outfalls which discharge into the lakefront at Fallingbrook Drive, Warden Avenue, Birchmount Road, Lakehurst Drive, Kennedy Road and the Scarborough Bluffs.
In the 1980s and 1990s, separate storm sewers were constructed in the majority of the study area thereby reducing the volume and frequency of the combined sewer overflows and eliminating basement flooding in many areas. Although much sewer separation has been done, combined flows are still large and hydraulic surcharging and basement flooding occurrences are avoided mainly by means of triggering many large overflows, or spillovers to the storm sewer system.
The City of Toronto has initiated an Addendum to the Scarborough Waterfront CSO and Stormwater Outfalls Control Class Environmental Assessment (EA) and Flood Protection Study in early 2020. The EA was originally completed in late 2011 and an Environmental Study Report (ESR) was prepared. The ESR identified solutions to control combined sewer overflows and storm sewer loadings to Lake Ontario, and to mitigate surface and basement flooding during large storm events for areas along the Scarborough waterfront (See Study Area Map).
The objective of the Addendum is to review and update the findings of the 2010 EA and to issue an ESR Addendum. The Addendum will recommend solutions to reduce the risk of future flooding, address combined sewer overflow control and address water quality.
This project was recommended in the Wet Weather Flow Master Plan (WWFMP), adopted by the City in 2003 to provide an integrated work program for managing wet weather flow.
The Addendum has identified the problem/opportunity, updated existing and future conditions, and evaluated the alternative solutions, recommended a preferred set of solutions, and identified measures to lessen any adverse impacts from the recommended solutions.
Public consultation is an important part of this study.
A virtual public meeting was held on November 26, 2020 to present the updated alternative solutions and a preliminary preferred set of solutions for public comment.