SELMER WWTP - Selmer, Tennessee Wastewater Treatment Plant

SELMER WWTP is a municipal wastewater treatment facility located in Selmer, Tennessee, within McNairy County. The plant serves a population of about 4,500 residents, placing it in the small-to-medium agglomeration category for US inland communities. As a publicly owned treatment works (POTW), it is part of the regional infrastructure supporting the town's residential and light industrial sectors. Under the US Clean Water Act, plants of this scale are typically required to provide secondary treatment, which involves biological processes to reduce organic pollutants and suspended solids. The National Pollutant Discharge Elimination System (NPDES) permit program, administered by the Tennessee Department of Environment and Conservation, governs discharge limits and monitoring requirements. The regulatory framework ensures compliance with water quality standards for the receiving water body. The plant discharges treated effluent into a local waterway that ultimately drains into the Tennessee River watershed. The Tennessee River flows westward to join the Ohio River, which then empties into the Mississippi River and eventually the Gulf of Mexico. This downstream chain connects the plant's operations to a vast river system supporting diverse aquatic life, including fish species such as catfish and bass, as well as migratory birds along the Mississippi Flyway.

The plant's discharge enters a tributary of the Tennessee River, which flows through the southeastern United States before joining the Ohio and Mississippi Rivers. This watershed supports a variety of aquatic habitats, including bottomland hardwood forests and wetlands that provide critical spawning and nursery areas for fish. The downstream environment is ecologically sensitive, with the Mississippi River Delta serving as a major estuarine zone for Gulf of Mexico species. Proper treatment is essential to prevent nutrient loading and maintain water quality in this interconnected system.