BIEL Wastewater Treatment Plant, Brügg, Bern, Switzerland

The BIEL wastewater treatment plant is located in Brügg, within the Verwaltungskreis Biel/Bienne in the canton of Bern, Switzerland. It serves a population of approximately 75,000 people from the surrounding urban area, including the city of Biel/Bienne. The plant is situated near the Aare river and the Bielersee lake, in the Seeland region. As a Swiss wastewater treatment facility serving a medium-to-large agglomeration, BIEL operates under the Swiss Water Protection Act (Gewässerschutzgesetz), which mandates advanced treatment to protect sensitive water bodies. Swiss regulations require tertiary treatment for plants of this scale, including phosphorus and nitrogen removal, to prevent eutrophication in lakes and rivers. The plant's capacity and treatment processes are designed to meet these stringent standards. The treated effluent from BIEL is discharged into the local water system, which flows into the Aare river and eventually into the Rhine river, a major European waterway. The Rhine basin supports diverse aquatic ecosystems and provides drinking water for millions downstream. The plant plays a critical role in maintaining water quality in the Bielersee and the broader Rhine watershed, protecting both ecological health and human uses.

The BIEL plant discharges into the Aare river, which flows into the Rhine river and ultimately the North Sea. The Aare and Rhine watersheds support diverse aquatic life, including fish species such as salmon and grayling. The Bielersee lake is a sensitive ecosystem that benefits from nutrient removal to prevent algal blooms. Swiss regulations ensure high treatment standards to protect these water bodies.