Haag ad Amper Wastewater Treatment Plant, Untermarchenbach, Bavaria

Haag ad Amper is a wastewater treatment plant located in Untermarchenbach, a district of Haag an der Amper in the Bavarian district of Freising, Germany. The plant serves a population of approximately 2,700 and is part of the municipal infrastructure for the region. The plant employs advanced treatment processes, meeting high standards for effluent quality. With a designed capacity of 3,600 cubic meters per day and an average discharge volume of 691 cubic meters per day, it 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, and the advanced level here exceeds that requirement. The treated effluent is discharged into local water bodies that eventually drain into the Amper River, a tributary of the Isar, which flows into the Danube and ultimately the Black Sea. The plant plays a key role in protecting the water quality of the Amper and downstream ecosystems.

The plant discharges into the Amper River, which flows into the Isar River, a major tributary of the Danube. The Danube drains into the Black Sea, making this plant part of a large international basin. The surrounding region is characterized by agricultural land and small settlements, and the plant helps maintain water quality for aquatic life and downstream users. The advanced treatment ensures low nutrient and pollutant loads, supporting the ecological health of the Amper and Isar rivers.