SOURIS LAGOON Wastewater Treatment Plant, Souris, North Dakota

SOURIS LAGOON is a municipal wastewater treatment facility located in Souris, North Dakota, serving a small population of 58 residents. The plant operates as a lagoon system providing secondary treatment, typical for small communities in the region. The plant has a designed capacity of 37.85 million gallons per year and discharges a similar volume annually. Under the US Clean Water Act, such facilities are regulated through the National Pollutant Discharge Elimination System (NPDES) permit program, which sets effluent limits to protect water quality. The treated effluent is discharged into local surface waters that eventually drain into the Souris River basin. The Souris River flows north into Canada and ultimately into Hudson Bay, making this plant part of a transboundary watershed. Proper treatment helps protect downstream aquatic ecosystems and drinking water sources.

The plant discharges into the Souris River basin, which flows northward through North Dakota and Manitoba, Canada, before joining the Assiniboine River and eventually reaching Hudson Bay. This watershed supports diverse aquatic life and provides habitat for migratory birds. The region's semi-arid climate means that maintaining water quality in the river is critical for both ecological health and downstream agricultural uses.