On 6 March, a ceremonial event marked the start of restoration works on Paradeisinsel, a Danube island located east of Vienna near Orth an der Donau. The event brought together representatives of institutions and partner organisations involved in the restoration activities, including viadonau, DANUBEPARKS, BOKU University, and the Donau-Auen National Park, as well as national and local authorities.
Among the official guests were Austria’s Federal Minister for Innovation, Mobility and Infrastructure Peter Hanke, National Park Director Edith Klauser, Helmut Habersack from the Institute for Hydraulic Engineering, Hydraulics and River Research (IWA) at BOKU University and coordinator of the DANUBE4all project, as well as Hans-Peter Hasenbichler, Managing Director of viadonau, and representatives of the municipalities of Orth an der Donau and Mannsdorf.
The restoration measures at Paradeisinsel were developed within the framework of the international DANUBE4all project funded by the Horizon Europe programme. The project brings together a broad partnership of organisations from across the Danube region to develop and demonstrate innovative and sustainable solutions for large-scale river and floodplain restoration.
Within this framework, DANUBEPARKS is responsible for the planning of the restoration measures at Paradeisinsel, working in close cooperation with viadonau, which leads the implementation of the construction works. Scientific support and monitoring are provided by BOKU University, while the activities are carried out in the area of the Donau-Auen National Park.
River islands represent unique and highly valuable habitats within river ecosystems. Their isolated position between the riverbank and the main current creates a mosaic of sheltered and dynamic habitats that support diverse flora and fauna. However, many of these natural features have been altered over time due to river engineering and sedimentation processes.
Paradeisinsel was originally formed during historical river regulation measures for navigation. Over time, increasing sediment accumulation between the island and the riverbank has reduced the natural river dynamics that are essential for maintaining diverse habitats.
The restoration measures aim to re-establish more natural conditions and enhance biodiversity along this section of the Danube. Key interventions include the removal of hard bank structures along approximately 2.7 km, the lowering of groyne roots, and the restoration of the side channel behind the island (Hinterrinnen). These measures will allow the riverbanks to develop more naturally, improve habitat diversity and create protected areas for fish, especially juvenile species.
At the same time, the project will improve the connection between the river and the surrounding floodplain, facilitating natural water exchange with the groundwater system and enhancing the capacity of the floodplain to absorb water during flood events. By reducing flow velocity in certain sections, the measures will also help counteract riverbed incision while maintaining suitable navigation conditions.
The Paradeisinsel restoration site is one of three pilot restoration areas within the DANUBE4all project along the Upper and Middle Danube. The pilot actions aim to demonstrate how nature-based solutions can simultaneously support ecological restoration, flood risk reduction and sustainable navigation.
To fully realise the restoration potential of the site, additional support has been secured from other funding instruments. Measures such as the lowering of groyne roots are supported by the European Open Rivers Programme through the Lost Paradeis project, while further riverbank restoration activities are supported by the Interreg Slovakia–Austria Programme through the DanubeRest project.
By combining these initiatives and funding sources, the restoration of Paradeisinsel represents an important example of coordinated efforts and synergies between multiple partners working towards healthier river ecosystems along the Danube. The measures are expected to contribute not only to improved ecological conditions but also to increased resilience of the river system in the face of climate change.
Photo: Kovacs