PRECIGNE Le Plessis Wastewater Treatment Plant, Précigné, France

PRECIGNE Le Plessis is a wastewater treatment plant located in Précigné, a commune in the Sarthe department of the Pays de la Loire region, France. The plant serves a population equivalent of 1,749, classifying it as a small agglomeration under the EU Urban Waste Water Treatment Directive (UWWTD). The plant employs advanced treatment processes, which go beyond the secondary treatment standard required by the EU UWWTD for agglomerations of this size. With a designed capacity of 2,500 m³/day and a current discharge volume of 312.02 m³/day, the plant operates well below its capacity. Advanced treatment typically includes nutrient removal (nitrogen and phosphorus) to protect sensitive receiving waters. 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 the longest river in France and flows into the Atlantic Ocean. The plant's advanced treatment helps protect the ecological health of the Sarthe and Loire rivers, supporting diverse aquatic life and downstream water quality.

The plant discharges into the Sarthe River basin, which flows into the Loire River, one of France's major rivers. The Loire estuary supports diverse aquatic ecosystems, including migratory fish species. Advanced treatment at the plant reduces nutrient loads, helping to prevent eutrophication in downstream waters.