Davos Wiesen Wastewater Treatment Plant, Bergün Filisur, Graubünden

Davos Wiesen is an advanced wastewater treatment plant located in Jenisberg, Bergün Filisur, in the canton of Graubünden, Switzerland. The plant serves a population of approximately 1,011 people and has a designed capacity of 1,750 m³/day, with an average discharge volume of 458.92 m³/day. As an advanced treatment facility, it employs processes that go beyond secondary treatment to remove nutrients and other pollutants, ensuring high effluent quality. The plant operates under Swiss water protection legislation, which aligns with the EU Urban Waste Water Treatment Directive (91/271/EEC) through bilateral agreements. For small agglomerations like this, advanced treatment is typically required in sensitive areas, such as Alpine regions, to protect receiving waters. The facility's advanced treatment level indicates it likely includes nitrogen and phosphorus removal, meeting stringent standards for discharge into sensitive environments. The treated effluent is discharged into local watercourses that drain into the Albula River, a tributary of the Rhine. The Rhine ultimately flows into the North Sea. The plant plays a crucial role in protecting the Alpine watershed, which supports diverse aquatic life and provides drinking water for downstream communities. Its advanced treatment helps maintain the ecological integrity of this high-altitude region.

The plant discharges into the Albula River basin, part of the Rhine catchment that flows through Switzerland, Germany, and the Netherlands into the North Sea. The Alpine watershed is ecologically sensitive, supporting cold-water fish species and pristine aquatic habitats. Advanced treatment ensures minimal nutrient loading, protecting downstream water quality in this region known for its biodiversity and tourism.