Item - 2022.IE30.13

The Infrastructure and Environment Committee recommends that:

1. City Council endorse the recommended Preferred Solution and Design for flood protecting the Rockcliffe-Smythe area as generally shown in Attachment 1 to the report (May 11, 2022) from the General Manager, Transportation Services and the General Manager, Toronto Water.

2. City Council request the Toronto and Region Conservation Authority, General Manager, Transportation Services and General Manager, Toronto Water to prepare the Environmental Study Report, issue the Notice of Completion, and put the Environmental Study Report in the public record in accordance with the requirements of the Municipal Class Environmental Assessment.

The Rockcliffe-Smythe area is located in Ward 5 (York South—Weston) and is the most flood vulnerable area in the Toronto and Region Conservation Authority's jurisdiction. There are hundreds of buildings within the regulatory floodplain of Black Creek and Lavender Creek; many of these properties experience frequent surface and basement flooding during severe storms. This is a result of riverine flooding and the overloading of the City of Toronto’s urban drainage system.

The City of Toronto, together with Toronto and Region Conservation Authority, initiated a Municipal Class Environmental Assessment to determine a preferred riverine flood mitigation strategy for the Rockcliffe-Smythe neighbourhood, and satisfy all four phases of the Municipal Class Environmental Assessment process. This study built upon recent advancements in the understanding of the causes of flooding within the community. Completion of the Municipal Class Environmental Assessment is the next step necessary to meet regulatory requirements prior to construction of flood mitigation measures.

This report recommends the Preferred Solution and Design for providing riverine flood protection to the Rockcliffe-Smythe area for endorsement by City Council. This report also reviews the opportunities explored to naturalize the Black Creek Channel as a part of establishing the alternative designs as directed by City Council.

The Preferred Solution involves significant infrastructure investment to modify the Black Creek and Lavender Creek Channels, construct a new flood protection wall, road realignment, as well as several bridge and culvert replacements. The entire project would be constructed in phases over an anticipated 10-year timeframe, and would flood protect 195 homes located in approximately 80 hectares (198 acres) of flood prone land from the 350-year flood area, and remove 222 buildings from the regulatory floodplain during a regional storm event, at an estimated cost of approximately $371 million.