ST PREX Wastewater Treatment Plant, Saint-Prex, Vaud, Switzerland

ST PREX wastewater treatment plant is located in Saint-Prex, a municipality in the district of Morges, Vaud, Switzerland. The plant serves a population of 11,276 and has a designed capacity of 1.00, indicating its role in managing municipal wastewater for the local community. Switzerland's water protection legislation, particularly the Waters Protection Act (GSchG), mandates stringent treatment standards for all wastewater treatment plants. For agglomerations of this size, secondary treatment with nutrient removal is typically required to protect sensitive water bodies. The plant's operational details align with these national standards. The treated effluent from ST PREX is discharged into the local watershed, which ultimately drains into Lake Geneva (Lac Léman), one of Europe's largest freshwater lakes. Lake Geneva supports diverse aquatic life and serves as a critical drinking water source for the region. The plant's performance is essential for maintaining the lake's water quality and ecological balance.

The plant discharges into the local watershed that flows into Lake Geneva, a major Alpine lake that drains via the Rhône River into the Mediterranean Sea. Lake Geneva supports a rich ecosystem, including fish species like Arctic char and whitefish, and is a vital resource for tourism and drinking water. Protecting this lake from nutrient pollution is a key environmental priority.