Species at Risk

Vianney-Legendre Fishway at the Saint-Ours Canal National Historic Site of Canada

Why reconstruct the Vianney-Legendre Fishway?

During reconstruction work carried out in 1967, the fishway that had been part of the dam for over 100 years wasn’t replaced. Since that time, the dam had been preventing the natural movement of fish along the Richelieu River.

This river is home to over 60 species of fish, including species whose survival in the Richelieu River is of concern - the Copper Redhorse, River Redhorse, Lake Sturgeon, American Shad and American Eel. These fish need to move between these areas to breed, and in the case of the American Eel, to feed.

Some of these species migrate thousands of kilometres. Others don’t travel far at all. But no matter what the distance, the movements are crucial to the health of fish populations. When obstacles like dams block fish movement, populations can suffer.

What is Park Canada doing to maintain the Vianney-Legendre Fishway?

One way to help fish move beyond obstacles like dams is to install fishways. These structures, sometimes also called fish passages or fish ladders, enable fish to swim over the barriers.

In spring 2001, Parks Canada, in collaboration with various partners, constructed a multi-species fishway to help fish navigate beyond the Saint-Ours dam.
The main, multispecies fishway responds to the requirements and characteristics of the Lake Sturgeon, American Shad, River Redhorse, and Copper Redhorse. A special fishway was added to accommodate the needs of the American Eel.

The design of the structure took a number of factors into consideration, including:

• the body size of the five main fish species expected to use the fishway
• the capacity of the fish to swim upstream
• the different periods of use
• the rate of water flow

The construction of these fishways represents an important effort to preserve fish biodiversity in the Richelieu River. The structures enable all the fish in the river to reach their spawning grounds, find suitable habitat, and move between populations for access to a wider gene pool. The fishway will also enable eels to regain access to feeding grounds, a factor that could benefit commercial fishing.

On May 30, 2002, the first Copper Redhorse was detected passing through the fishway at Saint-Ours. In 2005, over 20 Copper Redhorse fish were caught in the fishway. American shad, although found nearby, have not yet been caught or seen in the fishway. Between 2002 and 2005, the Vianney-Legendre Fishway allowed several thousand individuals of 36 fish species to navigate freely beyond the Saint-Ours dam, a major obstacle.

The project is a concrete measure to preserve biodiversity and maintain wild fish populations at risk at viable levels. We hope that it will promote the better management of uses of the Richelieu River, a major tributary of the St. Lawrence.

Partners in the Vianney-Legendre Fishway project include:

• Fisheries and Oceans Canada
• Société de la faune et des parcs du Québec
• Economic Development Canada
• Environment Canada
• Agriculture, Pêcheries et Alimentation Québec
• Transport Canada
• Fondation de la faune du Québec
• Projet Rescousse.

Parks Canada is responsible for the maintenance and operation of the Vianney-Legendre Fishway.