Construction on the long-term mitigation work in Cougar Creek will be starting soon. This page contains information on the Debris Retention Structure and will be updated on a regular basis during construction - keeping you up to date on impacts in the area.
Construction Timelines - Updated July 8, 2020
At this time we are still moving ahead with capital projects, this project is a key piece of infrastructure for the safety of the community.
- Construction has started. The multi-use trail on the west side of the creek is temporarily closed. Please see the map below for detours during this closure.
- Construction will be completed in 2021, with final landscaping complete in 2022
Long-Term Mitigation: Debris Flood Retention Structure
What will it look like?
- 34m high rock-filled embankment dam (not constructed out of concrete)
- Upstream and downstream faces covered by soil and seeded
- 20m wide rock-cut spillway on the east abutment that includes wildlife egress areas
What will it do?
- Existing channel and downstream culverts can accommodate 50-60 m3/s, but a natural event on the creek could easily reach 80 m3/s peak flow with 20% debris (fine sediment to large boulders, including gravel and woody debris)
- The Structure reduces peak flow to 45 m3/s. It further reduces quantity of debris and removes the larger debris
- The risk to downstream private and commercial properties, as well as infrastructure, is therefore reduced to an acceptable level
- There is no water retention during regular operation (dry dam) – water flows freely through a low level outlet
- A high capacity spillway is required to ensure flows can bypass the structure during an extreme flood event
Frequently Asked Questions
Alberta Parks and the Town of Canmore considered constructing an alternative route around the closure to access Cougar Creek Canyon. Due to the challenging steep terrain on Lady MacDonald and Grotto Mountain, Alberta Parks determined that closing access is the best alternative for ensuring public safety.
RIDGE Environmental Planning will serve as a third-party Environmental Monitor during the construction of the Cougar Creek Structure. The contract was awarded at a value of $159,000.