YVRE LE POLIN Wastewater Treatment Plant, Yvré-le-Pôlin, France

YVRE LE POLIN is a municipal wastewater treatment plant located in Yvré-le-Pôlin, a commune in the Sarthe department of Pays de la Loire, France. The plant serves a small population of approximately 1,000 residents and is designed to handle up to 2,000 cubic meters of wastewater per day, with an average discharge volume of 178.4 cubic meters per day. The plant provides secondary treatment, which is the standard biological treatment stage required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. Secondary treatment typically involves biological oxidation and sedimentation to reduce organic matter and suspended solids before discharge. The treated effluent is discharged into the local watershed, which ultimately drains into the Sarthe River, a tributary of the Loire River. The Loire is France's longest river and flows into the Atlantic Ocean. The plant plays a key role in protecting the water quality of the Sarthe and Loire rivers, supporting aquatic ecosystems and downstream water uses.

The plant discharges into the Sarthe River basin, which flows into the Loire River, one of Europe's last wild rivers. The Loire estuary supports diverse aquatic life, including migratory fish species such as Atlantic salmon and European eel. The plant's secondary treatment helps reduce nutrient and organic pollution, contributing to the ecological health of the downstream river system.