WALKER STP - Secondary Wastewater Treatment in Cass County, Minnesota

WALKER STP is a municipal wastewater treatment plant located in Cass County, Minnesota, United States. The facility serves a population of approximately 915 residents and is part of the region's water infrastructure. As a secondary treatment plant, it provides biological treatment to reduce organic pollutants before discharge. The plant has a designed capacity of 1,146.98 million gallons and reports an annual discharge volume of 760.87 million gallons. Under the US Clean Water Act, facilities of this scale are typically regulated through National Pollutant Discharge Elimination System (NPDES) permits issued by the Minnesota Pollution Control Agency, ensuring compliance with effluent limits. The treated wastewater is discharged into local waterways that drain into the Mississippi River basin, ultimately reaching the Gulf of Mexico. The plant plays a role in protecting downstream aquatic ecosystems and maintaining water quality in the region's lakes and rivers.

The plant discharges into receiving waters within the Mississippi River basin, which flows southward through multiple states to the Gulf of Mexico. This watershed supports diverse aquatic life and provides habitat for fish and migratory birds. The region's numerous lakes and wetlands are ecologically sensitive, and proper wastewater treatment helps prevent nutrient pollution that could lead to algal blooms and oxygen depletion.