Edwardsville STP - Wastewater Treatment Plant in Edwardsville, Illinois

Edwardsville STP is a municipal wastewater treatment facility located in Edwardsville, Illinois, serving a population of about 20,240. The plant is situated in Madison County, within the Mississippi River basin, and plays a key role in managing local wastewater. As a U.S. facility, Edwardsville STP operates under the Clean Water Act, administered by the Illinois Environmental Protection Agency. Plants of this scale typically provide secondary treatment, which includes biological processes to remove organic matter and suspended solids. The National Pollutant Discharge Elimination System (NPDES) permit program sets effluent limits to protect water quality. The treated effluent from Edwardsville STP likely discharges into a tributary of the Mississippi River, which flows south to the Gulf of Mexico. The Mississippi River supports diverse aquatic life and is a critical migratory corridor for birds and fish. Proper treatment helps reduce nutrient loading and protects downstream ecosystems.

Edwardsville STP discharges into the Mississippi River watershed, which drains into the Gulf of Mexico. The Mississippi River is a major ecological corridor, supporting diverse fish species and migratory birds. Nutrient pollution from wastewater can contribute to hypoxia in the Gulf, making effective treatment essential for downstream water quality.