MALVILLE 1 Le Pas Heulin Wastewater Treatment Plant, Malville, France

MALVILLE 1 Le Pas Heulin is an advanced wastewater treatment facility located in Malville, within the Pays de la Loire region of western France. The plant serves a population equivalent of 5,350 and is part of the municipal wastewater infrastructure managed by local authorities. Its location near the Loire-Atlantique department places it within a region characterized by a mix of rural and peri-urban settlements. The plant employs advanced treatment processes, which go beyond the secondary treatment required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. With a designed capacity of 3,200 m³/day and a reported discharge volume of 954.43 m³/day, the facility operates well within its capacity, indicating effective management of current wastewater loads. Advanced treatment typically includes nutrient removal, which is crucial for protecting sensitive water bodies. The treated effluent is discharged into local watercourses that ultimately drain into the Loire River estuary and the Bay of Biscay. The plant's advanced treatment helps safeguard downstream aquatic ecosystems, including the Loire estuary, a vital habitat for migratory fish and bird species. By maintaining high treatment standards, the facility supports regional water quality objectives under French and European regulations.

The plant discharges into local streams that flow into the Loire River, one of France's major rivers, which empties into the Bay of Biscay. The Loire estuary is an ecologically sensitive area supporting diverse aquatic life, including migratory fish such as Atlantic salmon and European eel. Advanced treatment at this plant helps reduce nutrient loads that could otherwise contribute to eutrophication in the estuary and coastal waters.