Les Orres Wastewater Treatment Plant - Alpine Facility in Provence-Alpes-Côte d'Azur

The Les Orres wastewater treatment plant is located in the Alpine commune of Les Orres, within the Provence-Alpes-Côte d'Azur region of southeastern France. The plant serves a population of 7,830, which fluctuates seasonally due to the town's status as a ski resort. As a facility in a mountainous area, it plays a key role in protecting the sensitive alpine environment. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), plants serving agglomerations between 2,000 and 10,000 population equivalent (PE) are required to provide secondary treatment. For sensitive areas, such as those in alpine regions, more stringent treatment may be mandated. It is expected to meet the regulatory standards for its size and location. The treated effluent is discharged into local watercourses that feed into the Durance River, a major tributary of the Rhône. The Durance flows through the Alps and eventually reaches the Mediterranean Sea via the Rhône delta. The plant's operation is critical for maintaining water quality in this alpine watershed, which supports diverse aquatic life and provides water for downstream communities and agriculture.

The plant discharges into the Durance River basin, which drains the southern French Alps. The Durance flows into the Rhône River, which empties into the Mediterranean Sea. This alpine watershed is ecologically sensitive, supporting species such as the European bullhead and the endangered Rhône streber. The plant's treatment performance directly affects water quality in this important river system.