LANNEMEZAN Wastewater Treatment Plant, Lannemezan, Occitanie, France

The LANNEMEZAN wastewater treatment plant is located in the town of Lannemezan, in the Hautes-Pyrénées department of the Occitanie region, southern France. The facility serves a population equivalent of 11,000, placing it in the small-to-medium agglomeration category under European Union classification. As a French plant, it operates under the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires secondary treatment for agglomerations of this size discharging into freshwater. The directive also mandates appropriate treatment to meet quality standards for the receiving environment. The plant's treated effluent is discharged into the local watershed, which ultimately drains into the Garonne River basin and then to the Atlantic Ocean via the Gironde estuary. The surrounding area is characterized by the foothills of the Pyrenees, with sensitive aquatic ecosystems that benefit from regulated wastewater treatment.

The plant discharges into the local stream network that feeds the Garonne River, a major watercourse flowing through southwestern France to the Atlantic Ocean. The Garonne basin supports diverse aquatic life, including migratory fish species such as salmon and eels. The region's water quality is managed under the EU Water Framework Directive, with monitoring to protect ecological status.