ST MARYS WWTP - Secondary Treatment Plant in West Saint Marys, Iowa

ST MARYS WWTP is a municipal wastewater treatment facility located in West Saint Marys, Iowa, within Warren County. The plant serves a small population of 134 residents and is part of the local infrastructure managed by the community. The plant provides secondary treatment, which is the standard level required by the US Clean Water Act for most municipal facilities. Secondary treatment typically involves biological processes to remove organic matter and suspended solids. The plant has a designed capacity of 75.71 million gallons per year and reports a discharge volume of 75.71 million gallons per year, indicating full utilization of its capacity. The treated effluent is discharged into local waterways that ultimately drain into the Mississippi River basin. The plant's operations are subject to National Pollutant Discharge Elimination System (NPDES) permits issued by the Iowa Department of Natural Resources, ensuring compliance with water quality standards to protect downstream ecosystems.

The plant discharges into tributaries of the Des Moines River, which flows into the Mississippi River and eventually the Gulf of Mexico. The local watershed supports diverse aquatic life and is part of the larger Mississippi River basin, an important ecological corridor for migratory fish and birds. The plant's secondary treatment helps reduce nutrient loads that could contribute to hypoxia in the Gulf.