ROMAGNIEU_La Calabre Wastewater Treatment Plant, Domessin, Auvergne-Rhône-Alpes

The ROMAGNIEU_La Calabre wastewater treatment plant is located in Domessin, within the Savoie department of the Auvergne-Rhône-Alpes region in France. It serves a population equivalent of 7,200, classifying it as a medium-sized agglomeration under French and EU regulations. 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. The regulatory framework ensures compliance with national standards for effluent quality. The plant discharges treated wastewater into the local water system, which ultimately drains into the Rhône River basin. The Rhône is a major European river that flows into the Mediterranean Sea, supporting diverse aquatic ecosystems and providing water for agricultural and urban uses downstream.

The plant's treated effluent enters the local watershed, which is part of the Rhône River basin. The Rhône flows southward through southeastern France, passing through the Camargue delta before reaching the Mediterranean Sea. This region supports diverse aquatic life, including fish species such as the European eel and various migratory birds. The watershed is ecologically sensitive due to agricultural runoff and urban pressures, making effective wastewater treatment crucial for maintaining water quality.