Kobernausserwald Wastewater Treatment Plant, Lohnsburg am Kobernaußerwald, Austria

Kobernausserwald is a wastewater treatment plant located in Lohnsburg am Kobernaußerwald, in the district of Ried, Upper Austria. It serves a population of approximately 3,168 people, placing it in the small agglomeration category under EU regulations. The plant is situated inland, away from coastal areas. The facility employs advanced treatment processes, which go beyond the secondary treatment standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. Its designed capacity is 4,800 cubic meters per day, and it currently treats an average daily flow of 974.57 cubic meters, indicating significant spare capacity. The treated effluent is discharged into local watercourses that eventually drain into the Danube River basin. This contributes to the protection of downstream ecosystems, including the Danube Delta, a region of high ecological importance. The advanced treatment helps minimize nutrient loading and supports good water quality in the receiving waters.

The plant discharges into small streams in the Innviertel region, which flow into the Inn River, a major tributary of the Danube. The Danube ultimately reaches the Black Sea, making the plant part of a vast international watershed. The advanced treatment reduces phosphorus and nitrogen loads, helping to prevent eutrophication in downstream lakes and the Danube Delta, a critical habitat for migratory birds and aquatic species.