Tiefenbach Treffelstein Wastewater Treatment Plant, Witzelsmühle, Bavaria

Tiefenbach Treffelstein is an advanced wastewater treatment plant located in Witzelsmühle, a hamlet near Treffelstein in the Cham district of Bavaria, Germany. The plant serves a population of approximately 2,405 and is part of the municipal infrastructure for the Tiefenbach administrative community. The plant employs advanced treatment processes, which go beyond secondary treatment to remove nutrients and other pollutants. With a designed capacity of 4,000 m³/day and a current discharge volume of 608.65 m³/day, the plant operates well below its capacity. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), plants serving agglomerations of this size are required to provide secondary treatment, but the advanced level here indicates a higher standard, likely due to sensitive receiving waters. The treated effluent is discharged into local watercourses that drain into the Regen River, a tributary of the Danube. The Danube ultimately flows into the Black Sea. The plant plays a key role in protecting the local aquatic ecosystem and downstream water quality in the Danube basin.

The plant discharges into small streams that feed the Regen River, which joins the Danube near Regensburg. The Danube is a major European waterway flowing into the Black Sea. The region's aquatic ecosystems support diverse species, including fish and invertebrates, and the advanced treatment helps reduce nutrient loading, preventing eutrophication in downstream lakes and coastal areas.