MARION STP - Marion, Kentucky Wastewater Treatment Plant

MARION STP is a municipal wastewater treatment plant located in Marion, Crittenden County, Kentucky. It serves a population of approximately 2,956 residents, classifying it as a small community system under US regulatory frameworks. The plant is situated near the Ohio River basin, which ultimately drains to the Mississippi River and the Gulf of Mexico. As a small municipal plant in the United States, MARION STP operates under the Clean Water Act's National Pollutant Discharge Elimination System (NPDES) permit program, administered by the Kentucky Energy and Environment Cabinet. Typical plants of this scale employ secondary treatment, often using activated sludge or lagoon systems, to meet state and federal effluent limits. The plant's treated effluent discharges into local waterways that flow into the Ohio River, a major tributary of the Mississippi River. The Ohio River supports diverse aquatic life and serves as a critical water resource for communities and industries. Proper treatment at MARION STP helps protect downstream water quality and the ecological health of the Mississippi River basin.

MARION STP discharges into local streams within the Ohio River watershed, which flows into the Mississippi River and ultimately the Gulf of Mexico. The Ohio River supports diverse aquatic species and is an important migratory corridor for fish. The plant's location in a rural agricultural area means its effluent can affect nutrient levels in downstream waters, making effective treatment essential for preventing eutrophication in the Gulf of Mexico's hypoxic zone.