ARNEGARD LAGOON Wastewater Treatment Plant, McKenzie County, North Dakota

ARNEGARD LAGOON is a wastewater treatment facility located in McKenzie County, North Dakota, serving a small population of 115 residents. The plant provides secondary treatment, a standard level for small communities in the United States, ensuring compliance with federal water quality standards. The plant has a designed capacity of 37.85 million gallons per year and discharges a similar volume annually. As a lagoon system, it relies on natural biological processes to treat wastewater. The facility operates under the US Clean Water Act, with permits issued by the North Dakota Department of Environmental Quality to regulate discharges and protect water quality. The treated effluent is discharged into local waterways that drain into the Missouri River watershed, eventually reaching the Gulf of Mexico. This small plant plays a role in maintaining the ecological health of the region's streams and rivers, supporting aquatic life and downstream water quality.

The plant discharges into local streams within the Missouri River basin, which flows into the Mississippi River and ultimately the Gulf of Mexico. The region's semi-arid climate and agricultural land use make water quality management important for sustaining aquatic habitats and downstream ecosystems. The plant's secondary treatment helps reduce nutrient loads that could otherwise contribute to algal blooms in receiving waters.