Rozellville SD 1 STP - Secondary Wastewater Treatment in Town of Day, Wisconsin

Rozellville SD 1 STP is a municipal wastewater treatment facility located in the Town of Day, Marathon County, Wisconsin, United States. The plant serves a small population of 278 residents, providing secondary treatment to meet state and federal water quality standards. The facility operates with a designed capacity of 113.56 units and currently treats an average daily flow of 56.78 units. As a secondary treatment plant, it employs biological processes to reduce organic matter and suspended solids, complying with the U.S. Clean Water Act's requirements for municipal wastewater treatment. The plant's performance is regulated under the National Pollutant Discharge Elimination System (NPDES) permit program, administered by the Wisconsin Department of Natural Resources. The treated effluent is discharged into a local waterway, contributing to the protection of the surrounding watershed. The plant plays a key role in maintaining water quality in the region, which ultimately drains into the Mississippi River Basin. By treating wastewater to secondary standards, the facility helps safeguard downstream aquatic ecosystems and supports the health of the local environment.

The plant discharges into a local stream that is part of the Wisconsin River watershed, which flows into the Mississippi River and eventually the Gulf of Mexico. The surrounding area is primarily rural and agricultural, with the treatment plant helping to prevent nutrient pollution and pathogen contamination in the receiving water body. This supports the ecological health of the stream and downstream habitats, including fish and macroinvertebrate communities.