Oberwiesenthal Wastewater Treatment Plant, Saxony, Germany

The Oberwiesenthal wastewater treatment plant is located in the town of Oberwiesenthal in the Erzgebirge (Ore Mountains) of Saxony, Germany. It serves a population of approximately 4,330 residents in this small mountain community. The plant provides advanced treatment, which goes beyond the secondary treatment required by the EU Urban Waste Water Treatment Directive for agglomerations of this size. With a designed capacity of 4,800 cubic meters per day and an average discharge volume of 649.50 cubic meters per day, the facility operates well below its capacity, indicating room for future growth or seasonal variations. The treated effluent is discharged into local watercourses that ultimately drain into the Zschopau River, a tributary of the Freiberger Mulde, which flows into the Mulde and then the Elbe River. The Elbe carries the water through Germany to the North Sea. The plant plays a key role in protecting the sensitive mountain streams and downstream aquatic ecosystems in the Elbe basin.

The plant discharges into small headwater streams in the Erzgebirge, which flow into the Zschopau River, a tributary of the Freiberger Mulde. These waters eventually reach the Elbe River, which drains into the North Sea. The region's mountainous terrain and cold-water streams support sensitive aquatic life, including brown trout and other cold-water species. Advanced treatment helps minimize nutrient and pollutant loads to these ecologically valuable waters.