Cascade Creek Restoration

Parks Canada is restoring habitat for aquatics species at risk within Cascade Creek. This 9 km section of stream, flowing from the Lake Minnewanka reservoir, has been impacted by many decades of flow manipulations. By restoring more natural flows and repairing stream habitat we hope to provide a home for native fish species.

Originally, the Cascade River flowed all the way to the Bow River. However, for many decades the dam on the Lake Minnewanka reservoir reduced it to a mere trickle. Over the years, the old river bed filled with fine sediment due to the low flows and lack of downstream connectivity.

Parks Canada prioritized aquatic restoration in its 2010 Banff Park Management Plan. Work began to carefully rehabilitate the waterway, but Mother Nature moved the work along faster than expected.

A sudden release of floodwater from the Minnewanka dam during the flood of 2013, followed the old Cascade river bed and scoured away years of accumulated sediment within a few days.

What is Parks Canada doing to help restore Cascade Creek?

After the effects of the flood, Parks Canada, TransAlta and the Department of Fisheries and Oceans teamed up to develop a plan to reconnect Cascade Creek with the Bow River. The multi-year plan will:

Remove non-native fish (Completed 2016)
Replace pipes and culverts to accommodate increased flows (Completed 2017)
Restore the physical structure of the creek channel (Completed 2019)
Install an upstream fish barrier, to prevent non-native fish from re-entering the stream channel (Completed 2019)
Restore a more natural flow to the stream (Ongoing)
Replant streamside vegetation (Ongoing)
Reintroduce native fish (Planned for 2022)

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  Restoration project map

What steps has Parks Canada taken in accomplishing these goals and how?

Removing non-native fish

Non-native brook trout are able to outcompete native fish species, so it was important that these fish be removed from the stream. This was accomplished through many seasons of electro-fishing*.

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Electro fishing is a tool for capturing fish where researchers use an electrical current to briefly stun the fish so they can be caught in a dip net.

Replacing pipes and culverts, to accommodate increased flows

To support healthy native fish populations Cascade Creek needs enough water in it year-round! This meant the historically seasonal creek needed an increase in water flow. To help support this, TransAlta replaced the old wooden outflow pipe from the dam with one that can safely manage increased flows. Culverts under roadways and the railway were also upgraded to accommodate the stream.

 

Improved TransAlta Minnewanka Dam outflow pipe                   New Minnewanka Road box culvert

Restoring the creek channels for native fish populations

Once complete, Cascade Creek will become a refuge for native fish. In particular, bull trout and/or westslope cutthroat trout (both Species at Risk).

These fish need cold, clear water to survive. The Cascade Creek bed has been re-graded to keep water flowing instead of warm and stagnant. In 2019 a large backhoe added riffles, pools and rocky runs to support all life stages of fish. Pools and riffles provide fish with a variety of currents, allowing them places to feed, rest and lay eggs.

Preventing non-native fish from re-entering the creek

As well in 2019, a steep drop was constructed at the downstream end of the stream to prevents non-native fish from swimming upstream and invading this newly restored habitat.

This makes Cascade creek a safe haven for native fish. Muskrats, beavers, insects, amphibians and birds will also benefit from the restoration.

 

Before restoration – inadequate stream-flows!                                 After habitat and flow restoration

Replanting streamside vegetation (Ongoing)

The stream banks will be planted with native shrubs, trees, grasses and other flowering plants to provide cover for the fish and to stabilize the newly constructed banks.

Healthy habitats help us all! Cascade Ponds is a beautiful recreation site. The restored creek ensures that everyone can enjoy this scenic area year-round. Improving the pipes and culverts reduces the risk of flood damage in the area. This means the Trans-Canada Highway, the railway line and the Legacy Trail stay safe.

What can you do to help?

• You can observe the restoration in progress along the Legacy Trail, between Cascade Ponds and the TransAlta power station.
• You can join the Parks Canada volunteer team and assist with replanting construction areas along Cascade Creek with native shrubs and grasses.
• You can encourage and support the protection and restoration of aquatic habitats where you live – and around the world!

Helen Irwin | Project Manager
helen.irwin@canada.ca