Sallisaw WWT - Sequoyah County, Oklahoma Wastewater Treatment Plant

Sallisaw WWT is a municipal wastewater treatment facility located in Sequoyah County, Oklahoma, United States. It serves a population of about 7,989 residents, placing it in the small-to-medium agglomeration category for US inland plants. As a US facility, Sallisaw WWT operates under the Clean Water Act and is subject to National Pollutant Discharge Elimination System (NPDES) permits issued by the Oklahoma Department of Environmental Quality. For plants serving populations around 8,000, secondary treatment is typically required to meet effluent limits for biochemical oxygen demand and total suspended solids. The plant discharges treated wastewater into a local water body that ultimately drains into the Arkansas River watershed, which flows into the Mississippi River and then the Gulf of Mexico. The facility plays a key role in protecting local water quality and downstream ecosystems.

The plant's treated effluent enters a receiving water body within the Arkansas River basin, which flows through Oklahoma and Arkansas before joining the Mississippi River. This watershed supports diverse aquatic life and provides water for agriculture and recreation. Downstream, the Mississippi River delivers nutrients and pollutants to the Gulf of Mexico, where seasonal hypoxia affects marine habitats. The plant's treatment performance is important for reducing nutrient loading in this sensitive downstream environment.