SALLES 33 Wastewater Treatment Plant, Salles, Nouvelle-Aquitaine, France

SALLES 33 is a municipal wastewater treatment facility located in Salles, a commune in the Gironde department of Nouvelle-Aquitaine, France. The plant serves a population of approximately 2,606 residents and is part of the region's water management infrastructure. Its advanced treatment level ensures high-quality effluent, meeting stringent French and European standards. As an advanced treatment plant, SALLES 33 employs processes that go beyond secondary treatment, likely including nutrient removal or disinfection. With a designed capacity of 3,000 cubic meters per day and a current discharge volume of 464.91 cubic meters per day, the plant operates well within its capacity, indicating efficient management. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), plants serving agglomerations of this size are required to provide secondary treatment, but SALLES 33 exceeds this requirement with advanced treatment. The treated effluent from SALLES 33 is discharged into the local watershed, which ultimately drains into the Arcachon Bay, a semi-enclosed marine basin on the Atlantic coast. This bay is ecologically sensitive, supporting diverse aquatic life and important migratory bird populations. The plant's advanced treatment helps protect the bay's water quality and biodiversity.

The treated wastewater from SALLES 33 enters the local stream network, which flows into the Arcachon Bay via the Leyre River and the Bassin d'Arcachon. This bay is a vital coastal ecosystem, supporting seagrass beds, oyster farming, and migratory bird habitats. The advanced treatment level helps minimize nutrient loading and pollution, preserving the ecological balance of this sensitive marine environment.