Hollenbach Wastewater Treatment Plant, Motzenhofen, Bavaria

The Hollenbach wastewater treatment plant is located in Motzenhofen, a district of Hollenbach in the Landkreis Aichach-Friedberg, Bavaria, Germany. It serves a population of 2,360 and operates with secondary treatment, a standard level for small agglomerations under the EU Urban Waste Water Treatment Directive (91/271/EEC). The plant's designed capacity is 3,000 m³/day, with an average daily discharge of 584.84 m³/day. As a secondary treatment facility, the plant removes organic matter and suspended solids through biological processes. For agglomerations under 10,000 population equivalent, the EU UWWTD requires appropriate treatment, which secondary treatment fulfills. The plant's discharge volume is well below its designed capacity, indicating operational headroom. The treated effluent is discharged into local watercourses that drain into the Danube River basin, ultimately reaching the Black Sea. The plant plays a key role in protecting the local aquatic environment by reducing nutrient and organic loads, supporting water quality in the region's streams and rivers.

The plant's discharge enters the local tributary network of the Danube River basin, which flows eastward through Bavaria and into the Black Sea. This region supports diverse aquatic life and is part of a larger watershed that includes ecologically sensitive floodplains and wetlands. The secondary treatment helps minimize eutrophication risks and maintains the ecological integrity of downstream water bodies.