Located at the limits of Châteauguay and Léry, the territory of the Saint-Jean stream is an extremely rich natural environment. First, it is partly made up of an important multispecies spawning ground in a floodplain, one of the last natural spawning grounds in Lake Saint-Louis. It is therefore the perfect breeding ground for many species of fish. Also, the site is home to several species of rare plants. To this end, it is one of the only protected places, with the refuge faunique Marguerite-D'Youville and the centre écologique Fernand-Seguin, where we find ergot-de-coq hawthorns, this rare plant. almost exclusive to the Chateauguay region. Finally, many birds also come to nest and feed there, as do various mammals, reptiles and amphibians. Now, nearly 70 hectares of land surrounding the Saint-Jean stream are protected in perpetuity thanks to notarized conservation easements.
For its part, the Parc de la Commune extends along the western branch of the Châteauguay river and faces Île Saint-Bernard. It features a one-kilometre multipurpose path, a grassy area and a playground for children. During the fishing season, the spot is especially popular with recreational anglers. The Parc de la Commune is part of Châteauguay’s network of parks.