A variant and feasibility study was carried out in order to construct a 700 m long island sidearm system and a 900 m long bank reclamation in the section of the Danube between the Abwinden-Asten power plant and the mouth of the Enn.  
The excavated material will be used for the optimisation of the Enns estuary (redesign according to the model test of the Vienna University of Technology).

By exploiting synergies, this project will achieve both an ecological improvement in the sense of the EU Water Framework Directive and a reduction in maintenance dredging and an improvement in fairway conditions in the Enn harbour. The project was launched in 2018 with the awarding and implementation of the submission planning.

Duration & Budget

Project period: 01.05.2018 - 31.12.2025
Total contract volume/contract volume viadonau: Total costs: EUR 232,453 

News and Activities

  • Based on the 2016 variant and feasibility study, four areas of ecological improvement measures in accordance with the EU Water Framework Directive are planned for the Danube section from the Abwinden-Asten power plant to the mouth of the Enns. The excavated material resulting from the construction of the island side arm systems and bank reconstructions will be used to optimise the Enns estuary according to a model test by the Vienna University of Technology in order to achieve a reduction in sediment deposits and the necessary maintenance dredging with the near-natural redesign of the harbour entrance area.
  • The 1.4 km long island side arm system Untere Langau was submitted to the authorities by VERBUND Hydropower GmbH at the end of 2022 as part of LIFE WILDisland.
  • viadonau has further developed the large side arm variant in the Enghagen measure area. Due to a lack of basic availability, the original variant (approx. 900 metres of bank reconstruction on the right bank on land owned by the Republic of Austria) will be pursued further. The submission planning, including hydraulic modelling, is to be completed in spring 2025 and also includes the Schlossau bank reconstruction (approx. 500 m on the left bank) as well as the guide structure and the groyne in Ennshafen. 



The project makes a substantial contribution to the implementation of measure 17. Execute restoration measures implementing the EU Water Framework Directive of the Action Programme for the Danube 2022 and the work package 10. Implementing renaturation, species and habitat protection projects in the sense of Good Ecological Status/Potential and Favourable Conservation Status along the Danube/March/Thaya of the Action Programme Danube 2030 of BMK.