Located between the towns of Sorel-Tracy and Trois-Rivières, Lake Saint-Pierre is the last broadening of the Saint Lawrence River before its estuary.
Upstream on this magnificent fluvial lake is an archipelago
made up of about a hundred islands, home to a wide variety
of plants and animals.
In spite of surrounding industrial activity, this ecosystem has retained 90% of its natural pristine state.
Lake Saint-Pierre has an area of 480 km². The maximum water depth is less than 3 metres, except in the Seaway where water depth reaches 11.3 metres.
Spring flooding and the gentle slope of its shores increase its surface to 660 km².
It’s the largest important freshwater flood plain in Quebec.
Nearly 50 % of the wetland environments of the Saint Lawrence River are in Lake Saint-Pierre.
In 1998, Lake Saint-Pierre was designated as a RAMSAR site, a recognition of the worldwide importance of its wetlands.
In 2000, UNESCO conferred upon Lake Saint-Pierre the status of “World Biosphere Reserve” in order to recognize the quality of its natural environment and the efforts made to preserve this unique ecosystem.