KA SoTERN Wastewater Treatment Plant, Nohfelden, Saarland, Germany

KA SoTERN is a former wastewater treatment plant located in the Sötern district of Nohfelden, in the Saarland region of Germany. The plant served a small population of 697 people and had a designed capacity of 2,000 cubic meters per day, indicating it was sized for a community of modest scale. The plant operated with advanced treatment, which goes beyond the secondary treatment required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. Advanced treatment typically includes nutrient removal (nitrogen and phosphorus) to protect sensitive water bodies. Although the plant is now closed, its design reflects the high environmental standards applied in German wastewater management. The plant's discharge likely entered local streams within the Nahe river basin, which flows into the Rhine River and eventually the North Sea. The Saarland region is characterized by forested hills and small rivers, making protection of water quality important for local ecosystems and downstream communities.

The plant's receiving waters are part of the Nahe river system, a tributary of the Rhine. The Rhine basin supports diverse aquatic life and is a major migratory corridor for fish. The advanced treatment level at KA SoTERN would have helped reduce nutrient loads, protecting downstream water quality in the Rhine and ultimately the North Sea.