Sulmeck Greith Gasselsdorf Wastewater Treatment Plant, Gasselsdorf, Steiermark

Sulmeck Greith Gasselsdorf is a wastewater treatment plant located in Gasselsdorf, a village in the municipality of Sankt Martin im Sulmtal, in the Bezirk Deutschlandsberg district of Steiermark, Austria. The plant serves a population of approximately 6,011 people, placing it in the small to medium agglomeration category under EU classification. As an Austrian plant, it operates under the EU Urban Waste Water Treatment Directive 91/271/EEC, which requires secondary treatment for agglomerations of this size. The directive also mandates appropriate treatment before discharge into inland waters, ensuring compliance with national water quality standards set by the Austrian Water Act (WRG 1959). The treated effluent is discharged into local watercourses that drain into the Sulm River, a tributary of the Mur River, which flows into the Drava and ultimately the Danube River system. This connection to the Danube basin highlights the plant's role in protecting downstream aquatic ecosystems in the Mur-Drava-Danube corridor.

The plant discharges into the Sulm River catchment, part of the Mur River basin, which flows into the Drava and then the Danube. This region supports diverse aquatic life, including fish species such as grayling and brown trout. The plant's treatment helps maintain water quality in this ecologically sensitive area, which is important for both biodiversity and downstream water uses.