Châteauneuf-sur-Isère Chef lieu Wastewater Treatment Plant, Auvergne-Rhône-Alpes

Châteauneuf-sur-Isère Chef lieu is a municipal wastewater treatment plant located in the commune of Châteauneuf-sur-Isère, within the Drôme department of the Auvergne-Rhône-Alpes region in southeastern France. The plant serves a population of approximately 2,967 residents, making it a small agglomeration under French and EU classification. The plant provides secondary treatment, which is the minimum standard required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for freshwater discharges from agglomerations of this size. With a designed capacity of 1,530 cubic meters per day and an average daily flow of about 529 cubic meters, the facility operates well within its capacity. The plant is managed as part of the municipal wastewater infrastructure serving the community. The treated effluent is discharged into the local watercourse, which flows into the Isère River, a major tributary of the Rhône River. The Rhône ultimately drains into the Mediterranean Sea. The plant plays a key role in protecting the water quality of the Isère and Rhône rivers, which support diverse aquatic ecosystems and are important for regional water resources.

The plant discharges into a tributary of the Isère River, which joins the Rhône River downstream. The Rhône is one of Europe's major rivers, flowing into the Mediterranean Sea. The watershed supports diverse aquatic life, including fish species such as the European eel and various migratory fish. The plant's secondary treatment helps reduce organic pollutants and protect the ecological health of these water bodies.