Bayonne Saint Bernard Wastewater Treatment Plant, Boucau, Nouvelle-Aquitaine

The Bayonne Saint Bernard wastewater treatment plant is located in Boucau, a commune in the Bayonne metropolitan area of Nouvelle-Aquitaine, France. The plant serves a population of approximately 8,733 people, placing it in the small-to-medium agglomeration category under French regulations. Its location near the Adour River estuary and the Bay of Biscay makes it part of a sensitive coastal environment. As a French wastewater facility, the plant operates under the European Union's Urban Waste Water Treatment Directive (91/271/EEC), which requires secondary treatment for agglomerations of this size. The directive also mandates more stringent treatment if the discharge enters sensitive areas, such as coastal zones. The plant's compliance with EU standards ensures a baseline level of treatment appropriate for its population served. The plant's treated effluent ultimately reaches the Adour River, which flows into the Bay of Biscay in the Atlantic Ocean. This coastal discharge point is ecologically significant, supporting diverse marine life and migratory fish species. The plant plays a key role in protecting water quality in the Adour estuary and the adjacent coastal waters, which are important for both biodiversity and local economic activities like fishing and tourism.

The Bayonne Saint Bernard plant discharges into the Adour River watershed, which flows into the Bay of Biscay (Atlantic Ocean). The coastal and estuarine environment supports diverse aquatic life, including migratory fish such as salmon and eels. The plant's location within 50 km of the coast means its discharge can influence nearshore water quality, making effective treatment essential for protecting marine ecosystems and recreational uses.