Karlsruhe Lagoon Wastewater Treatment Plant, Karlsruhe, North Dakota

Karlsruhe Lagoon is a municipal wastewater treatment facility located in Karlsruhe, North Dakota, United States. The plant serves a small population of 82 residents, reflecting the rural character of the area. It is situated in McHenry County, part of the northern Great Plains region. The plant provides secondary treatment, which is the standard level required under the U.S. Clean Water Act for municipal facilities. Secondary treatment typically involves biological processes to reduce organic matter and suspended solids. The plant has a designed capacity of 75.71 cubic meters per day and a current discharge volume of 37.85 cubic meters per day, indicating it operates well within its capacity. Treated effluent from the plant is discharged into the local watershed, which ultimately drains into the Souris River basin. This river system flows north into Canada, eventually reaching the Hudson Bay. The plant plays a key role in protecting local water quality and the downstream aquatic environment in this ecologically sensitive prairie region.

The plant discharges into the Souris River basin, a transboundary watershed that flows from North Dakota into Manitoba, Canada, and eventually into Hudson Bay. The region supports diverse aquatic life and migratory birds, making water quality management critical. The plant's secondary treatment helps reduce nutrient and organic pollutant loads, protecting downstream ecosystems in this semi-arid prairie landscape.