CARIGNAN DE BORDEAUX Wastewater Treatment Plant, Bouliac, Nouvelle-Aquitaine

CARIGNAN DE BORDEAUX is an advanced wastewater treatment plant located in Bouliac, within the Bordeaux metropolitan area of Nouvelle-Aquitaine, France. The plant serves a population of 3,804 and has a designed capacity of 3,000 m³/day, with an average discharge volume of 678.63 m³/day, indicating it operates well below its capacity. As an advanced treatment facility, it goes beyond secondary treatment to remove nutrients and other pollutants, meeting stringent French and EU standards. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), plants serving agglomerations of this size are required to provide secondary treatment, but advanced treatment is often implemented in sensitive areas to protect water quality. The plant discharges into the local watershed, which ultimately drains into the Garonne River and then the Gironde estuary, a major ecological and economic resource. The estuary supports diverse aquatic life and is an important migratory corridor for fish species. The plant's advanced treatment helps minimize nutrient loading and protect downstream ecosystems.

The plant discharges into the Garonne River basin, which flows into the Gironde estuary, the largest estuary in Europe. This estuary is ecologically sensitive, supporting diverse aquatic life and serving as a critical migratory corridor for species such as Atlantic salmon and European eel. Advanced treatment at the plant reduces nutrient and pollutant loads, helping to protect water quality in this important downstream environment.