Vilsheim Wastewater Treatment Plant, Altfraunhofen, Bavaria

The Vilsheim wastewater treatment plant is located in Altfraunhofen, a municipality in the Landkreis Landshut district of Bavaria, Germany. It served a population of approximately 1,766 people, classifying it as a small agglomeration under the EU Urban Waste Water Treatment Directive (UWWTD). The plant is now closed, but during its operation it provided secondary treatment, which is the minimum required by the UWWTD for freshwater discharges from agglomerations of this size. As a German facility, the plant operated under the national implementation of the EU UWWTD, which mandates secondary treatment for all discharges to freshwater and estuaries from agglomerations above 2,000 population equivalent (PE). For smaller plants like Vilsheim, secondary treatment is still typical to protect receiving water quality. The plant's designed capacity was 3,000 m³/day, and its actual discharge volume was 446.93 m³/day, indicating it operated well below capacity. The treated effluent from Vilsheim would have been discharged into a local watercourse, likely a tributary of the Isar River or the Kleine Vils, which ultimately drains into the Danube River basin. The Danube flows eastward through several countries before reaching the Black Sea. The plant's operation helped protect the local aquatic ecosystem and downstream water quality in the Danube catchment, which supports diverse fish species and migratory birds.

The Vilsheim plant discharged into a small watercourse within the Danube River basin. The Danube is Europe's second-longest river, flowing through ten countries and emptying into the Black Sea. The downstream environment includes ecologically sensitive floodplains and wetlands that support diverse aquatic life, including sturgeon and other migratory fish species. The plant's secondary treatment helped reduce organic pollution and protect these habitats.