Schornsheim Wastewater Treatment Plant, Undenheim, Rheinland-Pfalz

The Schornsheim wastewater treatment plant is located in Undenheim, within the Rhein-Selz region of Landkreis Mainz-Bingen, Rheinland-Pfalz, Germany. It served a population of 1,800 and is now closed. The plant was designed with a capacity of 2,500 m³/day and discharged an average volume of 455.54 m³/day. The plant provided advanced treatment, which goes beyond the secondary treatment required by the EU Urban Waste Water Treatment Directive for agglomerations of this size. Advanced treatment typically includes nutrient removal to protect sensitive water bodies. As a German facility, it operated under the national Wasserhaushaltsgesetz (Water Resources Act) and relevant state regulations. The treated effluent likely discharged into local watercourses that drain into the Rhine River basin, which flows through Germany and the Netherlands into the North Sea. The Rhine is a major European waterway supporting diverse aquatic life and providing drinking water for millions. The plant's advanced treatment helped reduce nutrient loads to this ecologically important river system.

The plant's discharge would have entered small streams in the Rhein-Selz area, which are tributaries of the Rhine River. The Rhine flows through Germany and the Netherlands before reaching the North Sea. This watershed supports diverse aquatic ecosystems, including migratory fish species such as salmon and eel. Advanced treatment at the plant helped minimize nutrient pollution, protecting downstream water quality in the Rhine and the North Sea.