Saint Joseph SD 1 STP | Advanced Wastewater Treatment in Town of Greenfield, Wisconsin

Saint Joseph SD 1 STP is an advanced wastewater treatment facility located in Town of Greenfield, La Crosse County, Wisconsin. The plant serves a small population of 650 residents, providing essential sanitation services for this rural community in the Driftless Area of southwestern Wisconsin. The plant operates with advanced treatment processes, which go beyond secondary treatment to remove nutrients and other pollutants. With a designed capacity of 227.12 million gallons per day and a current discharge volume of 140.06 million gallons per day, the facility operates well within its capacity. As a US plant, it is regulated under the Clean Water Act and likely holds an NPDES permit issued by the Wisconsin Department of Natural Resources. The treated effluent from Saint Joseph SD 1 STP is discharged into local streams that drain into the Mississippi River via the La Crosse River. The Upper Mississippi River is a major ecological corridor supporting diverse aquatic life, including fish, mussels, and migratory birds. The plant's advanced treatment helps protect downstream water quality in this nationally significant river system.

The plant discharges into tributaries of the La Crosse River, which flows into the Mississippi River near La Crosse, Wisconsin. The Upper Mississippi River is a biologically diverse ecosystem that supports over 260 fish species and 40 species of freshwater mussels. The region is characterized by steep bluffs and karst topography, making groundwater protection important. Advanced treatment at this plant helps reduce nutrient loading to the Mississippi River, which ultimately drains to the Gulf of Mexico.