Ringelai Wastewater Treatment Plant, Kühbach, Bayern, Germany

Ringelai wastewater treatment plant is located in the Kühbach area of Ringelai, within the Landkreis Freyung-Grafenau district in Bayern, Germany. The plant serves a population of approximately 1,837 people and is currently closed. It was designed with a capacity of 3,500 m³/day and treated an average discharge volume of 464.90 m³/day. The plant provides secondary treatment, which is the standard level required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. The directive mandates secondary treatment for populations between 2,000 and 10,000 in freshwater areas, and Ringelai's population falls within this range, ensuring compliance with European wastewater standards. The treated effluent from the plant is discharged into local water bodies that ultimately drain into the Danube River basin. The region's waterways support diverse aquatic life and contribute to the ecological health of the Danube, one of Europe's most important river systems. The plant's operation helps protect downstream water quality in the Danube and its tributaries.

The plant discharges into local streams that flow into the Danube River basin, which eventually reaches the Black Sea. The Danube supports a rich diversity of fish species and migratory birds, making water quality management critical for maintaining ecological balance. The surrounding Bavarian landscape includes forests and agricultural areas, where nutrient pollution from wastewater can impact sensitive aquatic habitats.