USEP Wastewater Treatment Plant, Henryville, Quebec

USEP is a municipal wastewater treatment plant located at 177 Rue Phénix in Henryville, Quebec, Canada. Serving a population of 1,112, it is a small-scale facility that plays a key role in treating domestic wastewater from the community. The plant is situated in the Montérégie region, near the Richelieu River watershed. The plant provides secondary treatment, which involves biological processes to reduce organic matter and suspended solids. As a small agglomeration in Canada, it operates under provincial regulations that align with federal guidelines under the Canadian Environmental Protection Act and the Fisheries Act. Secondary treatment is standard for communities of this size to protect receiving waters. The treated effluent is discharged into a local watercourse that ultimately drains into the Richelieu River and then into the St. Lawrence River. This watershed supports diverse aquatic life and is important for recreational and ecological functions. The plant's proximity to the coast (within 10 km) underscores the need for effective treatment to prevent nutrient loading and protect downstream ecosystems.

The plant discharges into a tributary of the Richelieu River, which flows northward into the St. Lawrence River near Sorel-Tracy. The St. Lawrence River is a major waterway that empties into the Gulf of St. Lawrence, an ecologically sensitive estuary. The region supports diverse fish species, including walleye and yellow perch, and provides habitat for migratory birds. Effective wastewater treatment is critical to prevent eutrophication and maintain water quality in this interconnected system.