AMBRIERES LES VALLEES Wastewater Treatment Plant, Ambrières-les-Vallées, France

AMBRIERES LES VALLEES is a wastewater treatment plant located in Ambrières-les-Vallées, in the Pays de la Loire region of northwestern France. The facility serves a population of approximately 1,883 residents, placing it in the small agglomeration category under French and European regulations. The plant employs advanced treatment processes, which go beyond the secondary treatment standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for inland plants of this size. Its designed capacity is 3,470 m³/day, with an average discharge volume of 335.92 m³/day. The plant operates under the French regulatory framework, which implements the EU directive through national legislation. The treated effluent is discharged into the local watershed, which ultimately drains into the Mayenne River, a tributary of the Loire River. The Loire flows into the Atlantic Ocean, making the plant part of a larger river basin that supports diverse aquatic ecosystems and is important for regional water quality management.

The plant discharges into the Mayenne River basin, which flows into the Loire River and then into the Atlantic Ocean. This watershed supports diverse aquatic life and is an important ecological corridor. The advanced treatment level helps protect downstream water quality in the Loire estuary and coastal zone.