Satillieu Wastewater Treatment Plant, Satillieu, Auvergne-Rhône-Alpes, France

The Satillieu wastewater treatment plant is located in the commune of Satillieu, in the Ardèche department of the Auvergne-Rhône-Alpes region, France. It serves a population of approximately 1,600 residents, classifying it as a small agglomeration under French and EU regulations. The plant is situated inland, away from coastal areas, and its operations are part of the local municipal wastewater infrastructure. The plant provides secondary treatment, which is the standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for freshwater discharges from agglomerations of this size. It has a designed capacity of 2,000 m³/day and reports an average daily discharge volume of 285.44 m³/day, indicating a utilization rate well below capacity. Secondary treatment typically involves biological processes to reduce organic matter and suspended solids. The treated effluent is discharged into a local watercourse, which ultimately flows into the Rhône River basin. The Rhône is one of Europe's major rivers, draining into the Mediterranean Sea. The plant's operations help protect the local watershed and downstream aquatic ecosystems from pollution, supporting water quality in the region.

The plant discharges into a local stream that is part of the Rhône River basin. The Rhône flows through southeastern France and into the Mediterranean Sea, supporting diverse aquatic life and providing water for agriculture and industry. The watershed includes sensitive ecosystems such as the Camargue delta, a critical habitat for migratory birds. Effective wastewater treatment is essential to prevent nutrient enrichment and contamination that could harm these downstream environments.