After more natural bank structures have been created at the mouth of the Fischa in autumn and winter 2019 as part of the EU-funded Austrian-Slovak INTERREG project "Alps Carpathian River Corridor", viadonau is now taking the next step in terms of revitalization of the Danube tributary. Still in the wetland remaining Danube gravel is removed and the groundwork is set for the development of a new biotope. Since the middle of September, constructions have started for the creation of a new, diverse habitat, from which wildlife typical of the river will benefit in particular.
In a first revitalization phase, the riverbank enforcement downstream of the confluence of the Fischa into the Danube was completely removed. Photo: © viadonau
In the course of the second phase of revitalization at the Fischa estuary, which began in mid-September, the level of the hinterland upstream of the estuary will be lowered. In this way, a flat branch is created with an intermittent connection to the river Fischa downstream. In the subject area there has already been some sort of still water area, which is now partially restored by removing the remaining gravel layer and made accessible again for life and diversity of a river-typical nature. Since the newly emerging water surface is under the influence of floods, it will quickly develop richly structured and, with favourable shallow water areas, serving as an ideal breeding ground and nursery, especially for fish, amphibians and macrozoobenthic organisms. Hidden and far away from disturbing influences, fish like Barbel and Common Nase in particular, who come together here every year, find a quiet and cosy “waiting room” before they continue migrating up the Fischa. Wildlife and waterfowl also benefit from the upgrading of the river habitat, which will quickly take possession of the new piece of wild river landscape.
The gravel removed during the construction work will be returned into the Danube bed load cycle and, for this purpose, dumped into the river at a suitable point as part of viadonau's proactive waterway management.
By implementing the revitalization measures, viadonau is investing in a sustainable future of ecologically intact river landscapes. The primary goal of the hydraulic engineering measures on the Fischa is the extensive restoration of the original river, floodplain and bank structures as well as increasing the quality of the habitat for fish populations typical in this area. In cooperation with other targeted river-ecological measures, the project contributes to the long-term improvement of the Fischa-Danube habitat network.
Further information:
https://rivercorridor.com/
http://www.viadonau.org/en/company/project-database/aktiv/alpine-carpathian-river-corridor
