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Fish compensation program

After the 2013 flood, The City completed several riverbank stabilization and rehabilitation projects at various locations along the Bow and Elbow Rivers. While necessary, these projects resulted in the loss of fish habitat.

The City recognized these impacts and, with support from both Alberta Environment and Parks and Fisheries and Oceans Canada, developed a plan to compensate for the damage and conserve this important habitat. The City’s plan has three main goals: mapping the existing fish habitat, determining habitat preferences, and creating and implementing a prioritized list of compensation projects.

Existing habitat was mapped to provide an updated record of what exists within the city limits. The Bow, Elbow, Nose Creek, West Nose Creek and Fish Creek were all included in the study. Fish habitat mapping breaks the river down into several habitat types, including runs, riffles, pools, snyes, backwaters, cascades and rapids.

Other features in the river were also documented such as the type of substrate (material on the bottom of the river), type of bank, and instream cover such as fallen trees that can provide protection and resting areas for fish. The habitat preferences of all local fish species were also studied.

What is bioengineering, and how does it help fish compensation?

City of Calgary

When plant roots and branches grow along the river's edge they weave together forming a sturdy network that helps hold soil in place. This organic structure protects the riverbank from erosion and provides natural habitat for birds, insects, fish and other wildlife.

Traditional engineered bank protection like rock riprap or concrete creates a hard barrier to protect infrastructure such as roads, bridges, pipelines and property from erosion. Since this strategy overwhelms most vegetation along the riverbank, root systems disappear, natural habitats are lost and biodiversity is threatened.

Shepard Landfill

Composting facility

​Biogineering combines vegetation and built components to shore up eroding riverbanks. Water loving shrubs, trees, grasses and other native plant matter take root among structural elements like timber crib wall, rock lining or boulders, fortifying the land.

The City often uses trees removed for various construction and infrastructue projects to create these new habitats, ensuring they do not go to waste. The resulting natural habitats support a diversity of birds, insects, fish and wildlife.

Construction updates

In total, over 45 potential compensation projects were identified and then ranked using a triple bottom line method that considered the social, environmental (beyond just fish), and economic impacts and benefits of each project.

The resulting top three ranking projects are all side channel reconnection projects and include works in the following areas:

In addition to the above three projects, The City is also working on additional high ranking projects where there are synergies with other ongoing city needs. One such project is the Inglewood Bird Sanctuary Reconnection Project which is looking at reconnecting the lagoon with the river while at the same time updating the lagoons hydraulic structures.

Should you have any questions on the fish habitat study or these projects, please contact 311.

Elbow Island Construction Update

  • Starting the week of April 30, contractors will be removing a few trees and cleaning debris from the island. There will be a traffic detour for up to three days.
  • Since our last update to the community (and engagement) in Fall 2018, we have now received regulatory approvals to begin construction.
  • Preliminary work will take place in March and will include the removal of trees on the island (this is necessary to rehabilitate the island and restore river flow), as well as, reduce the canopy of identified trees (this work is preventative in nature as it aims to prevent nesting birds in the spring). This work will be completed in March.
  • Major work will commence July 16, 2019 outside of the Restricted Activity Period, or RAP, which protects fish spawning season. Construction is anticipated to take one month, weather dependent.