Boran-sur-Oise Wastewater Treatment Plant - Hauts-de-France, France

The Boran-sur-Oise wastewater treatment plant is located in the commune of Boran-sur-Oise, within the Oise department of the Hauts-de-France region. It serves a population of approximately 1,240 residents, classifying it as a small agglomeration under French and EU regulations. The plant provides secondary treatment, which is the minimum standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for freshwater discharges from agglomerations of this size. Its designed capacity is 3,000 m³ per day, and current discharge volume averages 221.21 m³ per day, indicating significant reserve capacity. The treated effluent is discharged into the Oise River, a major tributary of the Seine. The Oise River flows through the region before joining the Seine near Conflans-Sainte-Honorine, ultimately reaching the English Channel. The plant plays a key role in protecting the Oise River's water quality and supporting the ecological health of the Seine basin.

The plant discharges into the Oise River, which flows into the Seine River and then into the English Channel. The Oise River supports diverse aquatic life and is an important corridor for migratory fish. The Seine basin is a densely populated and agriculturally intensive region, making nutrient removal from wastewater critical to prevent eutrophication in downstream coastal waters.