Within the frame of the transnational INTERREG-Project “Alpen Karpaten Fluss Korridor” (Alpine Carpathian River Corridor) viadonau revitalized the mouth of the tributary ‘Fischa’ into the Danube. Approximately 250 meters of bank enforcement were removed or lowered along the Danube. The newly designed river banks offer more room for development and enhance the habitat connectivity in the river system Fischa-Danube.
Photo: © viadonau
Photo: © viadonau
Together with the Danube, the Fischa forms a substantial network of habitats between Vienna and Bratislava, which is used by numerous plant and animal species as an area for migration. While the upper and middle reach of the 35-kilometer-long side-arm of the Danube still shows some ecologically valuable sections, the lower reach and mouth of the river suffer from morphological deficits instead, due to river bank enforcements made from armored stones.
During fall and winter of 2019 viadonau implemented river engineering measures at the mouth of the Fischa for a near-nature redesign of the banks. Roughly 10.000 cubic meters of gravel and amour stones were moved in the context of the renaturation.
While the existing river bank enforcement on the upstream side of the river mouth was lowered over a length of 125 meter, on the downstream section the rip-rap was completely removed over a length of an approximately 130 meters. “The revitalized river mouth allows Fischa and Danube to develop dynamically and form natural bank structures. Especially rheophile fish like the ‘Common Nase’ benefit from the renaturation at the Fischa, where diverse river bank habitats can now develop” explains viadonau project manager Julia Kneifel.
Alpine Carpathian River Corridor
Coordinated by the national park Donau-Auen and co-funded by the European Union and the state of Lower Austria the project “Alpen Karpaten Fluss Korridor” (Alpine Carpathian River Corridor) focuses on the improvement and protection of the connectivity of habitats for water bound organisms at the Austrian-Slovakian border region. The renaturation of the Fischa mouth is the first successfully completed out of a total of 13 planned pilot measures of the project and part of the viadonau Catalogue of Measures for the Danube to the East of Vienna. Further information about the projects of the “Alpen Karpaten Fluss Korridor” can be found here as well as in the viadonau project database.
