Mosinee WWTP - Wastewater Treatment Plant in Mosinee, Wisconsin

Mosinee WWTP is a municipal wastewater treatment facility located in Mosinee, Marathon County, Wisconsin. Serving a population of about 4,189, the plant is part of the community's essential infrastructure for managing domestic wastewater. As a small-scale facility, Mosinee WWTP operates under the U.S. Clean Water Act, which requires secondary treatment for municipal plants. The plant is subject to National Pollutant Discharge Elimination System (NPDES) permits issued by the Wisconsin Department of Natural Resources, ensuring compliance with effluent limits to protect water quality. The plant's treated effluent is discharged into the Wisconsin River watershed, which flows southward to the Mississippi River and ultimately to the Gulf of Mexico. This connection underscores the plant's role in safeguarding downstream aquatic ecosystems and regional water resources.

Mosinee WWTP discharges into the Wisconsin River basin, part of the Upper Mississippi River system. The Wisconsin River supports diverse aquatic life, including fish species such as walleye and smallmouth bass, and provides habitat for migratory birds. Downstream, the Mississippi River carries treated effluent to the Gulf of Mexico, where nutrient management is critical to prevent hypoxic zones.