Jassans-Riottier Wastewater Treatment Plant, Auvergne-Rhône-Alpes, France

The Jassans-Riottier wastewater treatment plant is located in the commune of Jassans-Riottier, within the Ain department of the Auvergne-Rhône-Alpes region in eastern France. The facility serves a population of approximately 37,068, classifying it as a medium-sized agglomeration under French and EU regulations. As a plant serving over 15,000 people, it is subject to the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires secondary biological treatment as a minimum standard. The directive also mandates more stringent tertiary treatment if the receiving waters are designated as sensitive areas, such as those prone to eutrophication. The plant's location inland, away from the coast, suggests its discharge likely enters a freshwater system. The treated effluent from the plant is discharged into the local watershed, which ultimately drains into the Saône River, a major tributary of the Rhône. The Rhône flows into the Mediterranean Sea. The plant plays a key role in protecting the water quality of the Saône and Rhône rivers, supporting aquatic life and downstream uses such as drinking water supply and recreation.

The plant discharges into the Saône River basin, which flows into the Rhône River and then the Mediterranean Sea. The Saône is a significant river in eastern France, supporting diverse aquatic ecosystems and providing water for agriculture and human consumption. The plant's operations help prevent nutrient pollution and protect the ecological health of these downstream waters.