Corydon STP Wastewater Treatment Plant, Corydon, Indiana

Corydon STP is a municipal wastewater treatment facility located in Corydon, Harrison County, Indiana, serving a population of about 4,200. The plant is situated near Indian Creek Trail and operates under the regulatory framework of the U.S. Clean Water Act, which requires National Pollutant Discharge Elimination System (NPDES) permits for all discharges to surface waters. As a small-to-medium agglomeration, the plant is expected to meet secondary treatment standards as a minimum. However, under the Clean Water Act, facilities of this scale typically employ secondary treatment (biological treatment) to reduce organic matter and suspended solids. The population served suggests a moderate flow that aligns with typical small community systems. The treated effluent from Corydon STP discharges into a local waterway that ultimately drains into the Ohio River, a major tributary of the Mississippi River. The Ohio River basin supports diverse aquatic life and provides drinking water for millions. The plant's operations are critical for protecting water quality in the region, particularly downstream ecosystems and recreational uses.

Corydon STP discharges into a tributary of the Ohio River, which flows into the Mississippi River and eventually the Gulf of Mexico. The Ohio River basin is ecologically significant, supporting diverse fish populations and providing habitat for migratory birds. The plant's effluent must meet state and federal water quality standards to protect downstream aquatic life and human uses such as fishing and recreation.