BALDWIN STP Wastewater Treatment Plant, Saint Croix County, Wisconsin

BALDWIN STP is a municipal wastewater treatment plant located in Saint Croix County, Wisconsin, United States. It serves the Town of Hammond and surrounding areas, with a population equivalent of approximately 3,555 people. The plant is situated inland, more than 50 km from the coast, and operates under the regulatory framework of the U.S. Clean Water Act. As a small-scale facility, BALDWIN STP is subject to National Pollutant Discharge Elimination System (NPDES) permitting requirements administered by the Wisconsin Department of Natural Resources. It is expected to meet state and federal effluent standards. The treated effluent from BALDWIN STP is discharged to local surface waters that ultimately flow into the St. Croix River, a tributary of the Mississippi River. The St. Croix River is a National Scenic Riverway and supports diverse aquatic life, including fish species such as walleye and smallmouth bass. The plant's operations contribute to protecting water quality in this ecologically significant watershed.

BALDWIN STP discharges into local streams that drain into the St. Croix River, which flows southward to join the Mississippi River near Prescott, Wisconsin. The St. Croix River basin is ecologically sensitive, supporting diverse aquatic habitats and migratory fish populations. The plant's location in a rural agricultural area means its discharge must meet stringent nutrient limits to prevent eutrophication in downstream waters.