Mareuil-sur-Lay route de St Florent Wastewater Treatment Plant, Pays de la Loire

The Mareuil-sur-Lay route de St Florent wastewater treatment plant is located in Mareuil-sur-Lay-Dissais, a commune in the Vendée department of Pays de la Loire, France. The plant serves a population of 1,429 and has a designed capacity of 3,300 cubic meters per day, with an average discharge volume of 254.93 cubic meters per day. 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. As a facility in a sensitive area, it likely incorporates nutrient removal to protect downstream water bodies. The treated effluent is discharged into the local watershed, which ultimately drains into the Atlantic Ocean via the Lay River and the Bay of Biscay. The plant plays a key role in maintaining water quality in this coastal region, supporting aquatic ecosystems and recreational uses.

The plant discharges into the Lay River, which flows through the Vendée region and empties into the Atlantic Ocean at the Bay of Biscay. This coastal watershed supports diverse aquatic life and is important for local fisheries and tourism. The advanced treatment helps minimize nutrient loading, protecting the estuary and coastal waters from eutrophication.