Mirande Wastewater Treatment Plant, Occitanie, France

The Mirande wastewater treatment plant is located in the commune of Mirande, in the Gers department of the Occitanie region, southern France. It serves a population of approximately 5,100 people, classifying it as a small to medium agglomeration under French and EU regulations. The plant employs advanced treatment processes, which go beyond the secondary treatment standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. Its designed capacity is 5,800 m³/day, with an average daily discharge volume of 909.83 m³/day, indicating ample reserve capacity. The treated effluent is discharged into the local watershed, which ultimately drains into the Garonne River basin and then to the Atlantic Ocean. The plant plays a key role in protecting the region's water quality and supporting the ecological health of downstream aquatic environments.

The Mirande plant discharges into a tributary of the Gers River, part of the Garonne basin, which flows into the Atlantic Ocean via the Gironde estuary. The watershed supports diverse aquatic life and is ecologically sensitive, particularly in the context of agricultural runoff and seasonal low flows. Advanced treatment helps mitigate nutrient loading and protects downstream habitats.