Etzelwang Wastewater Treatment Plant, Bayern, Germany

Etzelwang wastewater treatment plant is located in the municipality of Etzelwang, in the Bavarian district of Amberg-Sulzbach, Germany. The facility served a population of approximately 1,627 people, classifying it as a small agglomeration under the EU Urban Waste Water Treatment Directive (UWWTD). The plant is currently closed. The plant provided advanced treatment, which goes beyond the secondary treatment standard required by the EU UWWTD for smaller agglomerations. Advanced treatment typically includes nutrient removal (nitrogen and phosphorus) to protect sensitive water bodies. The plant had a designed capacity of 3,000 m³/day and a reported discharge volume of 411.75 m³/day. The treated effluent from the plant was discharged into local watercourses that drain into the Vils River, a tributary of the Naab, which flows into the Danube River and ultimately reaches the Black Sea. The plant's advanced treatment helped protect the ecological health of these waters, supporting aquatic life and downstream ecosystems.

The plant's discharge enters small streams in the Franconian Jura region, which flow into the Vils River. The Vils joins the Naab, a major tributary of the Danube. The Danube basin supports diverse aquatic species and is an important migratory corridor for fish. Advanced treatment at this plant helped reduce nutrient loading, protecting downstream water quality in the Danube and Black Sea.