On 6 March, partners and stakeholders gathered on the Danube east of Vienna to mark the start of restoration works on Paradeisinsel, a river island within the Donau-Auen National Park. The measures are implemented by viadonau in cooperation with BOKU University, the DANUBEPARKS Association, and the Donau-Auen National Park, with support from the Horizon Europe project DANUBE4all, the INTERREG Slovakia–Austria programme, and the European Open Rivers Programme.
For the WILDisland initiative, the restoration represents an important synergy project that reinforces the broader concept of island-based restoration along the Danube. The WILDisland approach recognises river islands as key indicators of healthy river dynamics and functioning floodplain ecosystems. By protecting and restoring these dynamic landscape elements, the initiative aims to strengthen ecological connectivity and biodiversity across the Danube corridor.
River islands: hotspots of biodiversity and natural river dynamics
River islands are unique ecological worlds within the river landscape. Their location between the riverbank and the main current creates sheltered zones with diverse habitats where characteristic riverine species can thrive. Where islands are allowed to develop naturally, they become important refuges for biodiversity and key components of a living river system.
In recent years, several projects along the Austrian Danube have demonstrated how island restoration can contribute to both ecological and hydraulic improvements. Notable examples include the restoration of Marktau in Upper Austria and Schwalbeninsel east of Vienna within the LIFE WILDisland project. The revitalisation of Paradeisinsel continues this approach, further strengthening the network of restored river islands along the Danube.
Restoration measures to revitalise Paradeisinsel
Paradeisinsel was originally formed during historic river regulation works for navigation. Over time, sedimentation between the island and the riverbank reduced natural river dynamics and limited ecological processes important for floodplain habitats.
The current restoration measures aim to reintroduce these natural dynamics. Hard bank protections along approximately 2.7 km of riverbank will be removed, while groyne roots will be lowered to allow the bank to develop more naturally without compromising navigation conditions. The restoration of the side channel behind the island (Hinterrinnen) will create sheltered habitats that are particularly important for juvenile fish and aquatic biodiversity.
Improving the connection between the river and its floodplain will also enhance groundwater exchange and increase the flood retention capacity of the surrounding landscape. At the same time, reducing local flow velocity helps counteract riverbed incision while maintaining navigable depths for shipping.
Synergies between restoration initiatives
The Paradeisinsel project illustrates how multiple initiatives can work together to achieve larger restoration outcomes. Within the DANUBE4all project, the site serves as a pilot for nature-based river restoration solutions in the Danube basin. Additional funding streams help unlock the full restoration potential of the site.
The European Open Rivers Programme supports the lowering of groyne roots to enable the development of a continuous back channel, while the INTERREG Slovakia–Austria project DanubeRest contributes to the renaturation of the downstream riverbank section. Together, these coordinated measures demonstrate how strategic cooperation between projects and funding instruments can significantly amplify restoration impacts.
By strengthening the network of revitalised river islands along the Danube, initiatives such as the Paradeisinsel restoration contribute to a broader vision of a living Danube corridor, where wild islands once again play their role as engines of biodiversity and resilience.
Photo credit: Dorn, Kovacs, Zinner
