Wallerstein Wastewater Treatment Plant, Ehringen, Bavaria

The Wallerstein wastewater treatment plant is located in Ehringen, a district of Wallerstein in the Bavarian administrative district of Donau-Ries, Germany. The plant served a population of approximately 3,463 people and is now closed. As a facility in Germany, it operated under the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires appropriate treatment for agglomerations of this size. The plant provided advanced treatment, which goes beyond the secondary treatment standard required by the EU directive for inland areas. Its designed capacity was 8,100 m³ per day, with an actual discharge volume of 876.40 m³ per day, indicating a low utilization rate before closure. The plant's operational status is closed, meaning it no longer treats wastewater. The treated effluent from the plant would have been discharged into local water bodies that eventually drain into the Danube River basin, as the region is part of the Danube watershed. The Danube flows into the Black Sea, supporting diverse aquatic ecosystems along its course. The plant's advanced treatment helped protect these downstream environments from nutrient pollution.

The plant is situated in the Danube River basin, which drains into the Black Sea. The local watershed includes small streams that feed into the Wörnitz River, a tributary of the Danube. The Danube supports a wide range of aquatic life, including migratory fish species, and its delta is an ecologically sensitive area. Advanced treatment at this plant would have reduced nutrient loads, helping to prevent eutrophication in downstream waters.