TREY Wastewater Treatment Plant, Trey, Vaud, Switzerland

TREY is a wastewater treatment plant located in the municipality of Trey, within the District de la Broye-Vully in the canton of Vaud, Switzerland. It serves a small population of 401 residents, reflecting its role in a rural or small community setting. The plant employs advanced treatment processes, which go beyond the secondary treatment standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC). Although Switzerland is not an EU member, its water protection legislation aligns with high standards, ensuring effective nutrient removal and protection of sensitive water bodies. The plant's designed capacity of 938.00 m³/day indicates it can handle peak flows, while the current discharge volume of 182.02 m³/day suggests ample reserve capacity. The treated effluent is discharged into the local watershed, which ultimately drains into the Broye River and then into Lake Neuchâtel, part of the Rhine basin. This region supports diverse aquatic life and is important for migratory birds. The advanced treatment helps minimize nutrient loading, protecting the lake's ecological balance.

TREY plant discharges into the Broye River, a tributary of Lake Neuchâtel, which is part of the larger Rhine basin. The lake is a significant freshwater ecosystem supporting diverse fish populations and migratory waterfowl. Advanced treatment reduces phosphorus and nitrogen inputs, helping to prevent eutrophication and maintain water quality in this ecologically sensitive region.