Advancing freshwater restoration

My Projects

The RaabSTAT project

• Key project facts
  The RaabSTAT project is the culmination of the studies on the Rába river and provides a summary evaluation of the results of the interventions to eliminate negative environmental impacts (pollution and hydromorphological impact). After the water pollution after the turn of the millennium, Austrian tanneries implemented technological improvements and limit value modifications for the river Rába. This was followed by investments in hydromorphology aimed at improving the connectivity and revitalisation/restoration of the river. In this project, we evaluated the results of the mitigation measures in a complex way. Biological and chemical sampling was carried out along the entire length of the river, across the border, with the involvement of Austrian and Hungarian experts. The results showed a clear improvement, but to achieve good ecological status, attention still needs to be paid to reducing diffuse pollution. The project also pointed out that climate change is increasing in low-flow periods, which makes the river's biota more sensitive to pollution, and that it may be necessary to review current loads.
• What impact did these projects have on biodiversity, if any?
  The RaabSTAT project was a monitoring and restoration project that had indirect but important impacts on biodiversity, particularly through water quality improvement and hydromorphological interventions:
  • Pollution Reduction: Technological upgrades at Austrian tanneries significantly reduced industrial discharges. Lower pollutant concentrations improved habitat quality for aquatic organisms.
  • Hydromorphological Improvements: The reconstruction of three weirs (two in Austria and one in Hungary) helped restore more natural flow conditions and river structure, which supports a more diverse range of habitats.
• What work challenges did you face and what approach did you take to solve them?
  The Rába project faced key challenges such as transboundary methodological differences, industrial pollution, and limited temporal data. These were addressed by harmonizing national monitoring results, enforcing stricter pollution controls and technology upgrades at Austrian tanneries, and integrating a decade of historical data to strengthen ecological assessments.
• What lessons learned are transferable to other places/projects?
  The project highlighted several transferable scientific lessons: long-term monitoring is essential to assess real ecological trends; harmonizing national methods allows for meaningful transboundary collaboration; hydromorphological improvements support habitat recovery; targeted pollution control—like industrial upgrades—can yield rapid benefits; and finally, climate change impacts, such as declining discharge, must be integrated into future water management and restoration planning.
• Is there anything you would do differently?
  The project conducted a one-time monitoring campaign. In hindsight, Olga would include multiple sampling events to better capture ecological dynamics and seasonal variability.
  
  Enhance early methodological coordination: Methodological differences between Austrian and Hungarian partners caused difficulties. She suggests that early, formal harmonization of methods would improve comparability and streamline joint analysis.
  
  Address climate trends proactively: A significant, unexpected finding was the gradual decline in river discharge, likely due to climate change. Future projects should incorporate climate-adaptive thresholds and flow expectations from the start.