Lake Mills WWTP: Wastewater Treatment in Lake Mills, Wisconsin

Lake Mills WWTP is a municipal wastewater treatment facility located in Lake Mills, Wisconsin, serving a population of about 7,033. The plant is situated inland, more than 50 kilometers from the coast, and operates under the regulatory framework of the United States Clean Water Act, which requires National Pollutant Discharge Elimination System (NPDES) permits for all discharges into surface waters. As a medium-sized agglomeration, the plant is expected to provide secondary treatment as a minimum standard under federal regulations. The plant's design and operation are subject to state and federal oversight to ensure compliance with water quality standards. The treated effluent from Lake Mills WWTP is discharged into a local water body that drains into the Rock River basin, ultimately reaching the Mississippi River and the Gulf of Mexico. This discharge contributes to the hydrological cycle of the region and must meet stringent limits to protect aquatic life and downstream water quality.

The plant discharges into a tributary of the Rock River, which flows southward through Wisconsin and Illinois before joining the Mississippi River. The Rock River watershed supports diverse aquatic habitats and is important for regional biodiversity. The discharge must comply with water quality standards to prevent nutrient enrichment and protect downstream ecosystems.