Reservoirs and Dams

The presence of reservoirs affects the reproduction of certain fish populations. Tidal range entails substantial habitat loss for lake trout, and this situation is particularly problematic in the Poisson Blanc reservoir, where numerous lake trout spawning grounds have been observed in shallow littoral zones. As for other dams in the watershed that have been built for cottaging, hydroelectric power generation, flood control or water level regulation, they restrict the free movement of fish, as do improperly installed or poorly maintained culverts.

Lake Water Quality

Increasing privatization of lakeshores and watercourses, the result of the growing popularity of cottaging activities, has caused the water quality of some lakes to deteriorate. Several other factors, such as logging, shoreline over-development, the use of fertilizer, construction of roads and the upkeep of obsolete septic systems have also contributed to this deterioration. All of these factors lead to changes in the aquatic environment, especially higher phosphorus levels and shoreline destabilization and erosion. In the long term, the result is eutrophication.

Invasive Species

Shoreline over-development also gives rise to another problem: the appearance of invasive species, which are becoming more and more frequent in Québec. Boating enthusiasts often neglect to clean their hulls when they transfer their craft from one body of water to another. This is sufficient to contaminate lakes that were formerly free of invasive species, as is the case for some lakes in the Lièvre River watershed. 

Adapted from "Pour la qualité de l'eau du bassin versant de la Lièvre: PORTRAIT&qquot;, published by the Comité du bassin versant de la rivière du Lièvre (COBALI), 2005.