FENNIMORE STP - Advanced Wastewater Treatment in Town of Fennimore, Wisconsin

FENNIMORE STP is an advanced wastewater treatment facility located in the Town of Fennimore, Grant County, Wisconsin. The plant serves a population of about 2,432 residents, providing essential sanitation services to this rural community in the Driftless Area of the Upper Midwest. The plant employs advanced treatment processes, which go beyond secondary treatment to remove nutrients and other pollutants. With a designed capacity of 2,346.95 cubic meters per day and an average daily flow of 719.23 cubic meters, the facility operates well within its capacity. As a US plant, it operates under the Clean Water Act's National Pollutant Discharge Elimination System (NPDES) permit program, which sets effluent limits to protect water quality. The treated effluent is discharged into a local water body that ultimately drains into the Mississippi River Basin. The plant's advanced treatment helps protect downstream aquatic ecosystems, including the Upper Mississippi River, which supports diverse fish and wildlife populations. Its inland location reduces direct marine impact, but its discharge contributes to the overall health of the Mississippi River watershed.

The plant discharges into a tributary of the Grant River, which flows into the Mississippi River near the Wisconsin-Iowa border. The Mississippi River in this region is a major migratory corridor for birds and supports diverse aquatic life, including freshwater mussels and fish species. The advanced treatment ensures that nutrient loads are minimized, helping to prevent eutrophication in downstream waters, including the Gulf of Mexico hypoxic zone.