MEILEN Wastewater Treatment Plant, Meilen, Zürich, Switzerland

The MEILEN wastewater treatment plant is located in Meilen, a municipality in the canton of Zürich, Switzerland, on the northeastern shore of Lake Zurich. Serving a population of approximately 37,504, the plant is part of the region's municipal wastewater infrastructure, handling domestic and industrial flows from the community. Switzerland enforces stringent water protection standards under the Federal Water Protection Act (Gewässerschutzgesetz), which mandates advanced treatment for discharges into sensitive water bodies. For agglomerations of this scale, tertiary treatment including phosphorus removal is typically required to protect the receiving waters. The plant's designed capacity is 1.00 (likely in thousands of cubic meters per day), indicating a moderate-scale facility. The treated effluent from the MEILEN plant discharges into Lake Zurich, a large pre-alpine lake that drains via the Limmat River into the Aare and ultimately the Rhine. Lake Zurich is a critical drinking water reservoir and recreational resource, and its ecological health depends on effective nutrient removal to prevent eutrophication. The plant's proximity to the lake underscores the importance of its treatment performance.

The MEILEN plant discharges into Lake Zurich, a deep, oligotrophic lake that flows into the Limmat River, then the Aare, and finally the Rhine River. The lake supports diverse aquatic life, including whitefish and perch, and is a vital drinking water source for the region. Effective nutrient removal is essential to maintain water quality and prevent algal blooms in this sensitive ecosystem.