Stonington WPCF - Primary Wastewater Treatment Plant in Stonington, Maine

Stonington WPCF is a wastewater treatment facility located in Stonington, Maine, a coastal town in Hancock County. The plant serves a small population of 780 residents and operates with a designed capacity of 662.45 thousand cubic meters per year, with an actual discharge volume of 151.42 thousand cubic meters per year. The plant provides primary treatment, which involves physical sedimentation to remove settleable solids. As a small facility in the United States, it is subject to the Clean Water Act and National Pollutant Discharge Elimination System (NPDES) permitting, which sets effluent limits based on the receiving water body's characteristics. The treated effluent is discharged into local waters that ultimately flow into the Atlantic Ocean. The coastal location means the discharge may affect nearby marine habitats, including shellfish beds and fish spawning areas. The plant's operation is important for protecting the water quality of Penobscot Bay and the Gulf of Maine ecosystem.

Stonington WPCF discharges into waters that drain into Penobscot Bay and then the Gulf of Maine, a productive marine ecosystem. The coastal environment supports diverse aquatic life, including lobster, groundfish, and migratory seabirds. Primary treatment provides limited nutrient removal, so the discharge may contribute to local nutrient loading, potentially affecting algal growth and dissolved oxygen levels in the bay.