Chemilly-sur-Yonne Wastewater Treatment Plant | Advanced Treatment, Yonne River

The Chemilly-sur-Yonne wastewater treatment plant is located in the commune of Chemilly-sur-Yonne, in the Yonne department of Bourgogne-Franche-Comté, France. It serves a population of approximately 2,336 residents, classifying it as a small agglomeration under French and EU regulations. The plant is situated at Rue du Stade, near the Yonne River. The facility employs advanced treatment processes, which go beyond the secondary treatment standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. With a designed capacity of 1,950 m³/day and an average daily discharge of 416.74 m³/day, the plant operates well within its capacity, indicating effective management of local wastewater flows. The treated effluent is discharged into the Yonne River, a tributary of the Seine, which flows through the Burgundy region before joining the Seine near Paris. The Seine ultimately drains into the English Channel. The plant's advanced treatment helps protect the Yonne River's water quality, supporting aquatic life and downstream uses such as recreation and agriculture.

The plant discharges into the Yonne River, which flows into the Seine River and eventually reaches the English Channel. The Yonne River supports diverse aquatic ecosystems and is an important water resource for the region. Advanced treatment at this plant reduces nutrient loads and pollutants, helping to maintain water quality in the Seine basin and mitigate eutrophication risks in downstream coastal waters.