LIEURAN BASSAN Wastewater Treatment Plant, Lieuran-lès-Béziers, Occitanie

LIEURAN BASSAN is a wastewater treatment plant located in Lieuran-lès-Béziers, a commune in the Hérault department of Occitanie, southern France. The plant serves a population of approximately 4,200 residents and has a designed capacity of 4,500 m³ per day, with an average discharge volume of 749.27 m³/day. The plant employs advanced treatment processes, exceeding the secondary treatment standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. Advanced treatment typically includes nutrient removal (nitrogen and phosphorus) to protect sensitive receiving waters. The plant operates under the French regulatory framework, which implements the EU directive through national legislation. The treated effluent is discharged into local watercourses that drain into the Mediterranean Sea via the Orb River or coastal lagoons. The region's aquatic ecosystems benefit from the plant's advanced treatment, which helps maintain water quality in downstream habitats that support diverse aquatic life and migratory species.

The plant discharges into the Orb River basin, which flows into the Mediterranean Sea near Béziers. The downstream environment includes coastal lagoons and marine habitats that are ecologically sensitive, supporting diverse aquatic life and migratory bird species. Advanced treatment at this plant helps reduce nutrient loading, protecting these ecosystems from eutrophication.