Piedmont Lagoon Wastewater Treatment Plant, Piedmont, Alabama

Piedmont Lagoon is a municipal wastewater treatment facility located in Piedmont, Calhoun County, Alabama. The plant serves a population of about 4,265 residents, placing it in the small-to-medium agglomeration category typical of rural Alabama communities. As a U.S. facility, Piedmont Lagoon operates under the Clean Water Act and is subject to National Pollutant Discharge Elimination System (NPDES) permits issued by the Alabama Department of Environmental Management. For plants of this scale, secondary treatment is the standard requirement, ensuring removal of organic matter and suspended solids before discharge. The plant's treated effluent is discharged into local waterways that ultimately drain into the Coosa River basin, part of the larger Mobile River system that flows into the Gulf of Mexico. This watershed supports diverse aquatic life and provides drinking water for downstream communities.

Piedmont Lagoon discharges into tributaries of the Coosa River, which flows southwest through Alabama to join the Alabama River and eventually the Mobile River delta and Gulf of Mexico. The Coosa River basin is ecologically significant, supporting species such as the Alabama sturgeon and various freshwater mussels. The plant's location inland, over 50 km from the coast, reduces direct marine impact but places importance on maintaining water quality in the river system.