Topcliff Avenue Erosion Control and Slope Stabilization Project

Toronto and Region Conservation Authority (TRCA) has proposed to undertake remedial flood and erosion control works near Topcliff Avenue, to protect private property from the hazards of slope instability and erosion.

Project Location

The project is located in the City of Toronto, near the intersection of Finch Avenue West and Jane Street.

Learn More About the Project

Project Background

This site was first identified to TRCA in 2013 following reports of a slope failure after the July 8, 2013 severe weather event. Erosion and slope instability issues on Topcliff Avenue are creating a risk to private properties located at the top of slope.

A slope failure occurred behind the property seen at the top of slope following the July 8, 2013 severe weather event. This property is at long-term risk from erosion and slope stability hazards. Source: TRCA, 2019.
Garbage and debris jams within the Black Creek tributary channel located at the bottom of slope below Topcliff Avenue are causing the channel to flood and creating additional erosion concerns for properties located at the top of slope. Source: TRCA, 2019.

This project is being planned in accordance with Conservation Ontario’s Class Environmental Assessment for Remedial Flood and Erosion Control Projects (amended 2013) (Class EA). The Class EA establishes a planning and approval process for a variety of projects that may be carried out by Conservation Authorities, including procedures and environmental planning principles for Conservation Authorities to follow to plan, design, evaluate, implement and monitor a project.

The below figure illustrates the Class EA planning process.

Class Environmental Assessment project planning process
Overview of the Class Environmental Assessment process.

Stakeholders will be invited to participate and provide input during various planning stages of the project. TRCA will coordinate these consultation opportunities and post updates to this web page.

The following alternative solutions were developed and evaluated by TRCA as part of the Class EA process for the project:

Slope Stabilization Alternatives:

Alternative 1 – Do Nothing

Alternative 2 – Improve drainage, minor earthworks and surficial erosion protection

Alternative 3 – Soil nail system

Alternative 4 Reinforced Soil Slope (RSS) system or Mechanically Stabilized Earth (MSE) structure

Black Creek Tributary Channel Alternatives:

Alternative 0 – Do Nothing

Alternative 1 – Channel realignment, decommission secondary channel formations

Alternative 2 – Channel improvements with armourstone wall bank protection

The results of the Class EA evaluation led to the identification of Slope Stabilization Alternative 4: Mechanically Stabilized Earth (MSE) Structure and Channel Alternative #2: Channel improvements with armourstone wall bank protection as the combined preferred alternative solution to address erosion and slope stability hazards within the project area. The following is a rendered image of what the preferred solution could look like below Topcliff Avenue.

This image has been rendered to represent what the combined preferred slope stabilization and erosion control solution could look like behind Topcliff Avenue. Source: TRCA, 2020.

Scope of Work

The proposed scope of work for this project includes stabilizing the valley wall along Topcliff Avenue and completing erosion control works along the base of the slope to ensure long-term stability.

Throughout 2021, TRCA intends to:

  • File the Class EA Project Plan for a 60-day* public review period and address any concerns about the preferred alternative solution
  • Work with affected landowners and develop the detailed designs for the preferred alternative solution

*Please note the public review period has been extended from 30 days to 60 days due to disruption caused by the COVID-19 pandemic. TRCA will make every effort to provide alternative means of distributing reports for public review given the closure of public libraries.

Following the 60-day review period of the Project Plan and the successful resolution of any concerns received during, TRCA intends to finalize the detailed design of the preferred solution and obtain the necessary approvals to proceed with the implementation of the selected alternative.

Construction Information

TRCA is currently in the planning stages for this project. Construction information will be posted following completion of all planning activities.

Public Notices

Notice of Intent (NOI)
TRCA formally initiated this project in 2020 through the issuance of a NOI. The NOI was published in the North York Mirror on February 13, 2020 to inform community members of the project.

Notice of Filing (NOF)
On January 8, 2020, TRCA circulated a NOF to interested stakeholders to notify them that the Class EA Project Plan has been filed for the 60-day public review period. All interested persons are invited to review the Class EA Project Plan and provide written comments to TRCA. Written comments must be received by March 9, 2021 and should be sent to Jaya Soora, Project Manager via mail or e-mail (see Contact Us).

Please click on the following link to find TRCA’s Project Plan for your review and comment: Topcliff Avenue Erosion Control and Slope Stabilization Project – Class EA Project Plan

Note: Hard copies of the Class EA Project Plan can be made available upon request to the Project Manager.

Notice of Construction (NOC)
Following completion of planning activities, TRCA will distribute a Notice of Construction to notify the local community and project stakeholders of the project’s construction timeline.

Progress Updates

End of year 2020:

  • TRCA, in conjunction with its engineering consultants, developed conceptual alternative solutions to address slope stability and erosion hazards affecting private properties along Topcliff Avenue
  • TRCA evaluated conceptual alternatives to identify the preferred alternative solution
  • TRCA issued a stakeholder engagement package to interested parties to solicit feedback and comments on TRCA’s identified preferred alternative solution
  • TRCA drafted the Class EA Project Plan

Contact Us

The Planning Team is located at TRCA’s Boyd Field Centre in Vaughan:
Restoration and Infrastructure Division, Erosion Risk Management
9755 Canada Company Avenue
Vaughan, Ontario
L4H 0A3

For more information regarding this project, please contact Jaya Soora, Project Manager:

Jaya Soora, Project Manager
Erosion Risk Management
Restoration & Infrastructure Division
9755 Canada Company Avenue, Vaughan L4H 0A3
(416) 661-6600 ext. 5533