Bassins d epuration Mistassini Wastewater Treatment Plant, Dolbeau-Mistassini, Quebec

Bassins d epuration Mistassini is a municipal wastewater treatment facility located in Dolbeau-Mistassini, Quebec, Canada. The plant serves a population of about 7,116 residents and is situated in the Saguenay-Lac-Saint-Jean region, an area known for its extensive freshwater systems and boreal forest environment. As a Canadian plant, it operates under provincial and federal regulations, including the Quebec Environment Quality Act and the Canadian Fisheries Act, which set standards for effluent quality. For a community of this size, typical treatment involves secondary biological processes to reduce organic matter and suspended solids before discharge. The plant's treated effluent is released into the local watershed, which drains into the Mistassini River and eventually reaches Lac Saint-Jean, a large freshwater lake. This lake is a key ecological feature, supporting diverse aquatic life and serving as a vital resource for local communities and industries.

The plant discharges into the Mistassini River, which flows into Lac Saint-Jean, a major freshwater lake in Quebec. Lac Saint-Jean is part of the Saguenay River system, which ultimately drains into the St. Lawrence Estuary. The lake supports a rich aquatic ecosystem, including fish species such as lake sturgeon and walleye, and is an important migratory corridor for birds. Protecting water quality in this watershed is critical for maintaining biodiversity and supporting local fisheries and tourism.