CAGNY Wastewater Treatment Plant, Frénouville, Normandy, France

The CAGNY wastewater treatment plant is located in Frénouville, near Caen in the Normandy region of France. It serves a population of approximately 3,170 people, classifying it as a small agglomeration under French and EU regulations. The plant is situated inland, more than 10 km from the coast, and operates within the Seine-Normandy river basin. 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. It has a designed capacity of 4,667 m³/day and currently treats an average daily flow of 565.52 m³/day, indicating significant spare capacity. The facility is part of France's national wastewater infrastructure, managed under the framework of the French Water Agencies and local authorities. The treated effluent is discharged into local watercourses that eventually drain into the English Channel via the Orne River and its estuary. The downstream environment includes the Baie de Seine, a coastal area that supports diverse marine life and is important for migratory birds. The plant's advanced treatment helps protect water quality in this ecologically sensitive region.

The plant discharges into the Orne River basin, which flows northward through Normandy and empties into the English Channel at the Baie de Seine. This coastal zone supports diverse aquatic life, including fish nurseries and migratory bird populations. The advanced treatment level ensures that nutrient and pollutant loads are minimized, helping to prevent eutrophication and maintain the ecological balance of the downstream estuary and marine environment.