BUTRY SUR OISE Wastewater Treatment Plant, Butry-sur-Oise, France

BUTRY SUR OISE is a wastewater treatment plant located in Butry-sur-Oise, a commune in the Val-d'Oise department of northern France. The plant serves a population of approximately 3,820 residents and is part of the municipal infrastructure managed under French water regulations. The plant employs advanced treatment processes, which go beyond the secondary treatment required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. With a designed capacity of 6,700 cubic meters per day and a current discharge volume of about 681 cubic meters per day, the facility operates well within its capacity, ensuring effective treatment. The treated effluent is discharged into the Oise River, a major tributary of the Seine. This contributes to the protection of the Seine watershed, which flows through Paris and into the English Channel. The advanced treatment helps reduce nutrient loads and pollutants, supporting aquatic life and downstream water quality in the Seine estuary.

The plant discharges into the Oise River, which flows into the Seine River and ultimately reaches the English Channel. The Seine watershed is ecologically sensitive, supporting diverse aquatic species and serving as a critical corridor for migratory fish. Advanced treatment at this plant helps minimize nutrient enrichment and pollution, protecting the river's ecological balance and the downstream marine environment.