Aigrefeuille-sur-Maine Wastewater Treatment Plant, Pays de la Loire, France

The Aigrefeuille-sur-Maine wastewater treatment plant is located in the commune of Aigrefeuille-sur-Maine, within the Loire-Atlantique department of the Pays de la Loire region in western France. This facility serves a population of approximately 2,000 residents, providing essential sanitation services for this small agglomeration. 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 design capacity of 5,500 m³/day and an actual discharge volume of 363 m³/day, the plant operates well below its capacity, indicating room for future growth or seasonal variations. The treated effluent is discharged into the local watershed, which ultimately drains into the Maine River, a tributary of the Loire River. The Loire River flows into the Atlantic Ocean, making this plant part of a larger network protecting the ecological health of the Loire estuary and coastal waters.

The plant discharges into the Maine River, which flows into the Loire River, one of France's longest rivers, before reaching the Atlantic Ocean. The Loire estuary is an ecologically sensitive area supporting diverse aquatic life, including migratory fish species. Advanced treatment helps reduce nutrient loads that could otherwise contribute to eutrophication in downstream waters.