Helping trout thrive by reconnecting streams
In Alberta, once numerous bull trout and other species are being impacted by development.
For decades, fish populations in two tributaries of the Waiparous Creek in southern Alberta’s foothills have been fragmented by several hanging culverts. Culverts allow roads to pass over streams, but the culverts installed over the Waiparous Creek tributaries were too small, causing flooding and scouring of the creek bed when high volumes of water were forced through the small culverts. Over time, and with the degradation of the creek bed, the culverts created a waterfall, impossible for the stream’s small native fish to cross. Isolated, the fish were more vulnerable to changes in the watershed, threatening their survival.
For the westslope cutthroat and bull trout that call the creek home, this is a problem, and Trout Unlimited Canada (TUC) wanted to do something to ensure the well being of these important but vulnerable species.
In 2022, thanks to funding from Land Stewardship Centre and the Watershed Stewardship Grant program, TUC replaced the hanging culverts with an open bottom arch culvert. This work reconnects the stream and improves conditions for trout and other fish in one of the tributaries of Waiparous Creek. When streams are reconnected by removing inadequate culverts, those species have the space and resources they need to thrive. Fish can now swim upstream if the stream dries up downstream. Once conditions improve, they can then swim downstream again and repopulate it.
“There's now unimpeded access for fish throughout this entire creek, all the way from the very top where it comes out of the ground, down to where it joins up with Waiparous Creek,” says Angela Ten, Management Biologist at TUC.
A year after replacing the culverts, TUC returned to see how the project had impacted the fish population. Upstream of the road, longnose dace, a very small non-game fish, was observed in the creek for the first time. This, Angela says, shows just how successful reconnection has been for the native fish of the stream.
“Finding longnose dace all the way upstream is impressive, because normally they're very weak swimmers. So, the fact that they were able to get past the crossing means that it is not a barrier in any way. Essentially, it’s an easy swim,” explains Angela.
Waiparous Creek has been identified as a priority watershed for the province, and TUC worked with the province, Cows and Fish, the Ghost Watershed Alliance Society, among other partners, to combine resources and knowledge to improve conditions for the trout in the stream.
“All these different groups bring different skills and backgrounds and knowledge. It allows us to do more by working together and using each other’s strengths,” says Angela.
TUC even invited the Whispering Pines Bible camp, who own the road that runs over the culverts, to get involved. Campers joined the TUC team as they sampled for fish after the old culverts were removed.
“The kids were super excited. They had no idea there were fish in the creek. It was a meaningful experience for them, even if it was just 20 kids. They talked about it all day. It made a valuable impact.”
Removing the culverts and replacing them with open arch culverts not only reconnected fish passage in the creek, but it allowed different organizations to connect and share the goal of improving the watershed, one action at a time.
You can read more about TUC’s project on their website.