Altenfelden Wastewater Treatment Plant, Oberösterreich, Austria

Altenfelden wastewater treatment plant is located in the municipality of Altenfelden, Bezirk Rohrbach, in the state of Oberösterreich, Austria. The plant serves a population of approximately 1,182 people, classifying it as a small agglomeration under Austrian and EU regulations. The plant employs advanced treatment processes, which go beyond the secondary treatment required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. With a designed capacity of 2,300 m³/day and an average discharge volume of 510.46 m³/day, the facility operates well below its capacity, indicating room for future growth or seasonal variations. The treated effluent is discharged into a local watercourse that ultimately drains into the Danube River basin. The Danube is a major European river flowing into the Black Sea, supporting diverse aquatic ecosystems and providing water for millions of people. The plant's advanced treatment helps protect downstream water quality and ecological health.

The plant discharges into a small stream that is part of the Danube River basin. The Danube flows eastward through Central and Eastern Europe before emptying into the Black Sea. This watershed supports a wide range of aquatic life, including fish species such as sturgeon and salmon, and provides important migratory corridors. Advanced treatment at the plant reduces nutrient loads, helping to prevent eutrophication in downstream lakes and the Black Sea.