ADDIS STP - Secondary Wastewater Treatment Plant in Addis, Louisiana

ADDIS STP is a municipal wastewater treatment facility located on South River Road in Addis, Louisiana, within West Baton Rouge Parish. The plant serves a small population of around 1,200 residents, providing secondary treatment to meet state and federal standards. As a secondary treatment plant, ADDIS STP uses biological processes to reduce organic matter and suspended solids. With a designed capacity of 1,135.62 cubic meters per day and a current discharge volume of 946.35 cubic meters per day, the facility operates under the U.S. Clean Water Act, which requires NPDES permits for all discharges. The plant's performance is regulated by the Louisiana Department of Environmental Quality. The treated effluent from ADDIS STP is discharged into the Mississippi River, a major waterway that flows into the Gulf of Mexico. This discharge contributes to the river's flow and must meet water quality standards to protect downstream aquatic life and recreational uses. The plant plays a key role in maintaining the ecological health of the lower Mississippi River basin.

ADDIS STP discharges into the Mississippi River, which drains into the Gulf of Mexico. The lower Mississippi River supports diverse aquatic species and is a critical migratory corridor for birds and fish. Nutrient loading from wastewater can contribute to hypoxic zones in the Gulf, making effective treatment essential for downstream ecosystem health.