YVERDON Wastewater Treatment Plant, Yverdon-les-Bains, Vaud, Switzerland

The YVERDON wastewater treatment plant is located in Yverdon-les-Bains, in the canton of Vaud, Switzerland. It serves a population of approximately 37,991 people, classifying it as a medium-sized agglomeration under Swiss water protection standards. The plant is situated near the shores of Lake Neuchâtel, the largest lake entirely within Switzerland. As a Swiss municipal wastewater facility, YVERDON is subject to the Swiss Water Protection Act (Gewässerschutzgesetz), which mandates advanced treatment to protect sensitive water bodies. For plants serving populations over 10,000, tertiary treatment including phosphorus removal is typically required to prevent eutrophication in lakes. The plant's designed capacity is 1.00 (likely in thousands of cubic meters per day), indicating it is sized to handle the local load. The treated effluent from YVERDON is discharged into the local hydrological network, ultimately reaching Lake Neuchâtel. This lake is a major freshwater resource and supports diverse aquatic life, including fish species such as perch and whitefish. The plant plays a critical role in maintaining water quality in the lake and the broader Rhine basin, as Lake Neuchâtel drains via the Zihl Canal into the Aare River and eventually the Rhine.

YVERDON discharges into the Lake Neuchâtel watershed, which is part of the Rhine basin. The lake is a large, deep, oligotrophic to mesotrophic water body that supports diverse aquatic ecosystems, including fish and migratory birds. Downstream, water flows through the Zihl Canal into the Aare River and then the Rhine, eventually reaching the North Sea. Protecting this lake from nutrient pollution is critical to prevent algal blooms and maintain water quality for recreation and biodiversity.