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 March 27, 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. We are following the direction of the provincial health authority and working with contractors to adjust their health & safety plan accordingly. Things are changing on a daily basis and we will adjust our projects as needed.
- Tree clearing work near the debris net has started and will be complete prior to April 15. Please expect minor disruptions in the area
- The main contractor should begin work this spring/summer
- Construction will be completed in 2022, with final landscaping complete in 2024
- Trails in the area will be impacted in the following way:
- Cougar Creek Canyon will be closed during construction
- The two multi-use pathways on either side of the creek will remain open - short closures may be necessary
- Montane trail and the Horseshoe trail systems will remain open - short closures may be necessary
- The Lady MacDonald Trail will remain open - short closures may be necessary
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