MOHALL LAGOON Wastewater Treatment Plant, Mohall, North Dakota

MOHALL LAGOON is a municipal wastewater treatment facility located in Mohall, Renville County, North Dakota. Serving a population of 783, the plant provides secondary treatment to meet state and federal water quality standards. The facility operates as a lagoon system, a common treatment method for small communities in the northern Great Plains. The plant has a designed capacity of 340.69 volume units and a reported discharge volume of 264.98, indicating it operates below its design capacity. As a secondary treatment facility, it meets the minimum requirements under the US Clean Water Act for municipal wastewater treatment. The plant is regulated under the National Pollutant Discharge Elimination System (NPDES) permit program, administered by the North Dakota Department of Environmental Quality. The treated effluent from MOHALL LAGOON is discharged into local surface waters that drain into the Souris River basin. The Souris River flows north into Canada and eventually into Hudson Bay. The plant plays a key role in protecting downstream water quality and aquatic habitats in this transboundary watershed.

MOHALL LAGOON discharges into local streams that are part of the Souris River basin. The Souris River flows north through North Dakota and Manitoba, Canada, ultimately draining into Hudson Bay. The watershed supports diverse aquatic life and is an important migratory corridor for waterfowl. The plant's secondary treatment helps reduce nutrient and pathogen loads, protecting downstream ecosystems in this semi-arid region.