Aich Assach Wastewater Treatment Plant - Assach, Steiermark, Austria

Aich Assach is an advanced wastewater treatment plant located in the village of Assach, within the municipality of Aich, in the district of Liezen, Steiermark, Austria. The plant serves a population of approximately 3,162 people, making it a small-scale facility in the alpine region of the Enns Valley. The plant operates with advanced treatment processes, which typically include nutrient removal beyond secondary treatment. With a designed capacity of 3,500 m³/day and an actual discharge volume of 397.80 m³/day, the plant operates well below its capacity, indicating room for future growth. As an Austrian facility, it complies with the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires appropriate treatment for sensitive areas. The treated effluent is discharged into local watercourses that eventually drain into the Enns River, a major tributary of the Danube. The plant plays a key role in protecting the water quality of the Enns and downstream ecosystems, including the Danube Delta, by removing nutrients and pollutants before discharge.

The plant discharges into small streams that flow into the Enns River, which is part of the Danube basin. The Enns River supports diverse aquatic life and is an important corridor for migratory fish. The advanced treatment ensures that nutrient loads are minimized, protecting downstream water bodies from eutrophication and maintaining ecological balance in the alpine and subalpine environments of Steiermark.