Protecting infrastructure and fish habitat with riverbank and channel modifications

Kananaskis River Alignment

The June 2013 flood eroded a bank of the Kananaskis River, exposing the Evan Thomas Wastewater Treatment Plant’s utilities, putting infrastructure and the community at risk. Alberta Environment and Parks reached out to us to help.

First, we focused on key themes for this project: environmental value, regulatory objectives, and visitor experience related to design and construction. We then considered the unique hydrology of the river as well as stable and serviceable erosion protection.

The installation of armored spurs protects the site from future erosion. Boulders placed along the designed thalweg, the line of lowest elevation within the river, create habitat complexity and protect it during various flow events. Rock vanes build positive hydraulic effects for the aquatic habitat, while bioengineering includes willow plantings, native cobbles, and cover for riparian vegetation. Lastly, a constructed riffle matches existing pre-construction conditions.

Realigning the river and protecting critical infrastructure from future flood events improves the resiliency of the village community and maintains environmental safety in this prized recreational area. Authorization from Department of Fisheries and Oceans Canada recognizes that the project will create even more aquatic habitat.