Tappen Lagoon Wastewater Treatment Plant, Tappen, North Dakota

Tappen Lagoon is a municipal wastewater treatment facility located in Tappen, a small town in Kidder County, North Dakota. The plant serves a population of approximately 197 residents, reflecting the rural character of the area. As a lagoon-based system, it provides secondary treatment to meet state and federal standards. The plant has a designed capacity of 75.71 volume units and discharges a similar volume of treated wastewater. Under the U.S. Clean Water Act, facilities of this scale are typically regulated through the National Pollutant Discharge Elimination System (NPDES) permit program, administered by the North Dakota Department of Environmental Quality. Secondary treatment is the minimum standard for municipal plants, ensuring removal of organic matter and suspended solids. Treated effluent from Tappen Lagoon is discharged into local surface waters that drain into the Missouri River watershed. The Missouri River system supports diverse aquatic life and provides water for agriculture and recreation downstream. Proper treatment helps protect these resources from nutrient pollution and pathogens.

Tappen Lagoon discharges into local streams that flow into the Missouri River, a major tributary of the Mississippi River system. The Missouri River in North Dakota supports fish species such as walleye and catfish, and its riparian zones provide habitat for migratory birds. The plant's secondary treatment reduces organic load and suspended solids, helping to maintain water quality in this agriculturally influenced region.