La Chaux-de-Fonds Wastewater Treatment Plant - Neuchâtel, Switzerland

La Chaux-de-Fonds wastewater treatment plant is located in the city of La Chaux-de-Fonds, in the canton of Neuchâtel, Switzerland. The plant serves a population of about 47,750, placing it in the medium agglomeration category for Swiss wastewater infrastructure. Switzerland's Water Protection Act (GSchG) and its ordinances set stringent standards for wastewater treatment. Plants serving agglomerations of this size are typically required to implement advanced treatment processes, including nutrient removal, to protect sensitive water bodies. The facility is part of the national network that ensures high-quality effluent standards. The treated wastewater from the plant is discharged into the local watershed, which ultimately drains into the Doubs River and then into the Rhine basin. This water body supports diverse aquatic life and is important for regional ecology. The plant plays a key role in maintaining water quality in the Jura region.

The plant discharges into the local watershed that feeds the Doubs River, a tributary of the Rhine. The Rhine basin is a major European waterway supporting diverse ecosystems and providing drinking water for millions. The Jura region's karst geology makes groundwater protection critical, and the plant's treatment helps prevent nutrient pollution in downstream lakes and rivers.