Montréal Rehabilitated Wastewater Treatment Plant | Montréal, Occitanie, France

The Montréal rehabilitated wastewater treatment plant is located in the commune of Montréal, in the Aude department of Occitanie, southern France. The facility serves a population of approximately 3,622 residents, placing it in the small agglomeration category under French and EU 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 agglomerations of this size. With a designed capacity of 3,000 m³/day and an actual discharge volume of 646.16 m³/day, the plant operates well below its capacity, indicating room for future growth or seasonal variations. The treated effluent is discharged into the local watershed, which ultimately drains into the Mediterranean Sea via the Aude River system. The plant's advanced treatment helps protect downstream water quality and supports the ecological health of the region's rivers and coastal environment.

The plant discharges into the Aude River basin, which flows through the Occitanie region and empties into the Mediterranean Sea near Narbonne. The downstream environment supports diverse aquatic life, including fish species such as the European eel and various migratory birds. Advanced treatment reduces nutrient loads, helping to prevent eutrophication in the coastal zone.