DESVRES Wastewater Treatment Plant, Desvres, Hauts-de-France

The DESVRES wastewater treatment plant is located in Desvres, a commune in the Pas-de-Calais department of Hauts-de-France, France. It serves a population equivalent of approximately 9,800, classifying it as a small to medium agglomeration under European Union regulations. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), agglomerations of this size are generally required to provide secondary treatment, with more stringent tertiary treatment if discharging into sensitive areas. The plant's compliance with these standards is managed by the relevant French water agency, which oversees permits and monitoring to protect water quality. The treated effluent from DESVRES is discharged into the local watershed, which ultimately drains into the English Channel via the Liane River or nearby coastal streams. This region supports diverse aquatic life and is important for migratory fish species. The plant plays a key role in maintaining the ecological health of the downstream environment.

The DESVRES plant discharges into the local watershed that flows into the Liane River, which empties into the English Channel near Boulogne-sur-Mer. This coastal area supports diverse marine and estuarine habitats, including nursery grounds for fish and feeding areas for seabirds. The plant's operations help protect these ecosystems from nutrient pollution and pathogens, contributing to the overall health of the Channel's coastal waters.