SWEA CITY STL Wastewater Treatment Plant, Kossuth County, Iowa

SWEA CITY STL is a municipal wastewater treatment plant located in Kossuth County, Iowa, United States. The facility serves a small population of 634 residents and operates under the regulatory framework of the U.S. Clean Water Act, which requires secondary treatment for municipal discharges to protect water quality. The plant provides secondary treatment, a standard biological process that removes organic matter and suspended solids. It has a designed capacity of 227.12 megaliters and an annual discharge volume of 189.27 megaliters, indicating moderate utilization. As an inland facility, it does not directly impact coastal waters. The treated effluent is discharged into local waterways that drain into the Upper Mississippi River basin. This region supports diverse aquatic life and agricultural activities, making effective wastewater treatment essential for maintaining downstream water quality and ecosystem health.

The plant discharges into tributaries of the Upper Mississippi River basin, which flows into the Mississippi River and eventually the Gulf of Mexico. This watershed supports a variety of fish and wildlife, and its water quality is critical for both ecological balance and human uses such as recreation and agriculture. The secondary treatment helps reduce nutrient loads that could contribute to hypoxia in the Gulf.