LANDEVANT Wastewater Treatment Plant, Landévant, Bretagne, France

The LANDEVANT wastewater treatment plant is located in Landévant, a commune in the Morbihan department of Bretagne, France. It serves a population of approximately 5,355 people, placing it in the small-to-medium agglomeration category under French and EU regulations. The plant is situated near the Voie Express de Nantes à Brest, within the Lorient urban area. 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 7,600 m³/day and an actual discharge volume of 955.32 m³/day, the plant operates well below its capacity, indicating room for future growth or seasonal variations. As a French facility, it is subject to national regulations transposing the EU directive, with permits issued by the local prefecture or water agency. The treated effluent is discharged into the local watershed, which ultimately drains into the Atlantic Ocean via the Blavet River or nearby coastal waters. The region's aquatic ecosystems, including estuaries and coastal zones, benefit from the plant's advanced treatment, which reduces nutrient loads and protects water quality in the sensitive marine environment of the Gulf of Morbihan and the wider Bay of Biscay.

The plant discharges into the watershed of the Blavet River, which flows into the Atlantic Ocean near Lorient. The downstream environment includes the Gulf of Morbihan, a semi-enclosed marine area known for its rich biodiversity and important shellfish farming. Advanced treatment helps minimize nutrient pollution, protecting seagrass beds and migratory fish species in this ecologically sensitive coastal zone.