ARUDY INTERCOMMUNALE Wastewater Treatment Plant, Arudy, France

ARUDY INTERCOMMUNALE is an advanced wastewater treatment plant located in Arudy, within the Pyrénées-Atlantiques department of Nouvelle-Aquitaine, France. The facility serves a population of 3,660 and has a designed capacity of 4,700 m³/day, with an average discharge volume of 652.94 m³/day. It operates under the French regulatory framework, which implements the EU Urban Waste Water Treatment Directive (91/271/EEC). The plant employs advanced treatment processes, which go beyond secondary treatment to remove nutrients and other pollutants. This level of treatment is typical for facilities discharging into sensitive areas, such as those upstream of ecologically important water bodies. The plant's capacity utilization is moderate, indicating efficient operation relative to its design. The treated effluent is discharged into the local watershed, which ultimately drains into the Gave d'Ossau river, a tributary of the Gave d'Oloron. This river system flows through the Pyrenees foothills and joins the Gave de Pau before reaching the Adour River and the Bay of Biscay. The advanced treatment helps protect downstream aquatic ecosystems, including fish populations and migratory species.

The plant discharges into the Gave d'Ossau river, which flows into the Gave d'Oloron, part of the Adour basin. This watershed supports diverse aquatic life, including salmonid populations, and is an important migratory corridor for Atlantic salmon. The advanced treatment ensures nutrient removal, reducing the risk of eutrophication in downstream waters, including the Bay of Biscay.