FAYETTEVILLE STP - Secondary Wastewater Treatment in Cahokia Heights, Illinois

FAYETTEVILLE STP is a municipal wastewater treatment plant located in Cahokia Heights, Illinois, within Saint Clair County. The facility serves a small population of 382 residents and operates as part of the region's wastewater infrastructure. Its location near the Mississippi River places it within a major watershed system. The plant provides secondary treatment, a standard level required by the U.S. Clean Water Act for facilities of this scale. With a designed capacity of 189.27 megaliters and an annual discharge volume of 151.42 megaliters, the plant operates below its capacity. Under the National Pollutant Discharge Elimination System (NPDES), the plant must comply with effluent limits to protect water quality. The treated effluent likely discharges into a tributary of the Mississippi River, which flows into the Gulf of Mexico. The Mississippi River basin supports diverse aquatic life and is a critical migratory corridor for birds and fish. The plant's discharge contributes to the overall nutrient load in the basin, which is a concern for downstream hypoxia in the Gulf.

The plant discharges into the Mississippi River watershed, which drains into the Gulf of Mexico. The Mississippi River basin is ecologically significant, supporting diverse aquatic species and serving as a major migratory route. Downstream, nutrient pollution from wastewater and agriculture contributes to seasonal hypoxia in the Gulf, making treatment standards important for regional water quality.