Dunseith Lagoon Wastewater Treatment Plant, Dunseith, North Dakota

Dunseith Lagoon is a municipal wastewater treatment facility located on Peace Garden Avenue in Dunseith, Rolette County, North Dakota. The plant serves a population of approximately 773 residents and is classified as a small-scale treatment system typical of rural communities in the northern Great Plains. The plant provides secondary treatment, which is the standard required by the US Clean Water Act for municipal wastewater facilities. With a designed capacity of 264.98 megaliters and an annual discharge volume of 189.27 megaliters, the facility operates within its capacity. As a lagoon-based system, it relies on natural biological processes to treat wastewater before discharge. The treated effluent is discharged into local waterways that drain into the Souris River basin, which flows north into Canada and eventually into Hudson Bay. The plant's operation is critical for protecting downstream water quality in this transboundary watershed, which supports agricultural irrigation and aquatic habitats.

The plant discharges into the Souris River watershed, which flows northward through North Dakota into Manitoba, Canada, and ultimately reaches Hudson Bay. This region is part of the Prairie Pothole Region, an ecologically sensitive area that provides critical habitat for migratory waterfowl and supports diverse aquatic life. The secondary treatment process helps reduce nutrient loading and protect downstream ecosystems.