ST OMER EN CHAUSSEE Wastewater Treatment Plant, Saint-Omer-en-Chaussée, France

ST OMER EN CHAUSSEE is a wastewater treatment plant located in Saint-Omer-en-Chaussée, a commune in the Oise department of Hauts-de-France, northern France. The plant serves a small population of about 1,317 residents and has a designed capacity of 3,000 m³/day, with an average discharge volume of 234.95 m³/day, indicating it operates well below its capacity. The plant employs advanced treatment processes, which go beyond secondary treatment to remove nutrients and other pollutants. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), agglomerations of this size (under 2,000 population equivalent) are typically required to provide appropriate treatment, and the advanced level here suggests a commitment to high effluent quality, possibly due to sensitive receiving waters. The treated effluent is discharged into local watercourses that eventually drain into the Seine River basin, which flows into the English Channel. The region's water bodies support diverse aquatic life and are important for agriculture and recreation. The plant's advanced treatment helps protect downstream ecosystems from nutrient pollution and other contaminants.

The plant discharges into local streams that are part of the Seine River basin, which ultimately flows into the English Channel. The Seine basin is ecologically significant, supporting diverse fish species and migratory birds. Advanced treatment at this plant helps reduce nutrient loads, protecting downstream water quality and aquatic habitats from eutrophication.