BACKUS CS Wastewater Treatment Plant, Backus, Minnesota

BACKUS CS is a municipal wastewater treatment plant located in Backus, Cass County, Minnesota, along the Paul Bunyan Trail. The facility serves a small population of 238 residents, reflecting the rural character of the area. As a secondary treatment plant, it provides biological treatment to reduce organic matter and suspended solids before discharge. The plant's designed capacity is 143.85 million gallons per year, matching its current discharge volume. Under the US Clean Water Act, facilities of this scale are typically permitted through the National Pollutant Discharge Elimination System (NPDES), administered by the Minnesota Pollution Control Agency. Secondary treatment is the standard requirement for municipal plants in the United States, ensuring compliance with effluent limits for biochemical oxygen demand and total suspended solids. The treated effluent from BACKUS CS is discharged into local waterways that ultimately drain into the Mississippi River basin. The plant plays a key role in protecting downstream water quality in the region's lakes and rivers, which support recreational activities and aquatic habitats. Its location inland, away from coastal areas, reduces direct marine impact but emphasizes the importance of maintaining water quality in freshwater ecosystems.

The plant discharges into local streams that flow into the Mississippi River basin, eventually reaching the Gulf of Mexico. This watershed supports diverse aquatic life and is important for regional water supply and recreation. The secondary treatment process helps reduce nutrient loading, which is critical for preventing eutrophication in downstream lakes and rivers.