WUERENLINGEN Wastewater Treatment Plant, Siggenthal Station, Aargau, Switzerland

WUERENLINGEN is a wastewater treatment plant located in Siggenthal Station, within the municipality of Würenlingen in the canton of Aargau, Switzerland. It serves a population of about 8,975 people, placing it in the small to medium agglomeration category under Swiss and EU classification systems. Switzerland enforces stringent wastewater treatment standards under the Waters Protection Act (Gewässerschutzgesetz), which mandates secondary treatment for all communities and tertiary treatment in sensitive areas. For a plant of this scale, typical treatment includes mechanical and biological processes, often with phosphorus removal to protect receiving waters. The plant's treated effluent discharges into the local watershed, which ultimately drains into the Aare River, a major tributary of the Rhine. The Aare flows through the Swiss Plateau and into the Rhine near Koblenz, eventually reaching the North Sea. This catchment supports diverse aquatic life and is important for regional water quality.

The plant's discharge enters the local drainage network that feeds the Aare River, a key tributary of the Rhine. The Aare basin supports diverse aquatic ecosystems, including fish species such as brown trout and grayling. Downstream, the Rhine is a major European waterway with significant ecological and economic importance. Swiss regulations require advanced treatment to minimize nutrient loading and protect these waters from eutrophication.