MESSEI Wastewater Treatment Plant, Messei, Normandie, France

MESSEI is a wastewater treatment plant located in Messei, a commune in the Orne department of Normandie, France. The plant serves a population of approximately 2,350 people, placing it in the small agglomeration category under French and EU regulations. The plant employs advanced treatment processes, which go beyond the secondary treatment required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. Its designed capacity is 2,500 m³/day, with an average daily discharge volume of 419.24 m³/day, indicating ample reserve capacity. The treated effluent is discharged into the local watershed, which ultimately drains into the English Channel via the Orne River and its tributaries. The plant's advanced treatment helps protect downstream aquatic ecosystems, including sensitive areas that support diverse freshwater and estuarine life.

The plant discharges into the Orne River basin, which flows northward through Normandie and into the English Channel at Ouistreham. The downstream environment includes estuarine and coastal habitats that support migratory fish species and diverse aquatic communities. Advanced treatment at this plant helps reduce nutrient loading and protect water quality in the river and its receiving coastal waters.