Due to the flood disaster in September 2024, Vienna's Danube Island and the issue of flood protection versus renaturation increasingly became the focus of discussions on social media. On the one hand, the Danube Island was praised as a prime example of renaturation and the - not uncontroversial - EU Renaturation Regulation; on the other hand, it was argued that the Danube Island, as a flood protection project, was at risk of being renaturated precisely because of the EU Renaturation Regulation. Both arguments must be rejected as legally incorrect, although from a legal point of view the implementation of a “Danube Island 2.0” would not be easy for legal reasons alone:

History of the Danube Island

On September 12, 1969, the Vienna City Council of the time passed the not uncontroversial resolution for a flood protection project, which provided for the construction of Vienna's Danube Island. Just one year later, approval was granted under water law and in 1972 construction began on the Danube Island, a 21 km long and up to 250 m wide artificial island between the Danube and the new Danube a few meters below.

In November 1972, the Vienna City Council also decided to hold a “competition to obtain design and utilization alternatives for the future Danube Island” and in 1986 the construction of the Danube Island was finally completed.

The Danube Island 2.0

In particular, project applicants for today's flood protection projects can only dream of these approval times. This is not because work was more efficient in 1970 or because projects were less complex, but simply because the legal approval parameters have changed massively and new legal approval matters such as environmental impact assessments have been added. Civil society is also much more critical of such projects.

The fact that this creates potential for conflict and project delays is demonstrated quite aptly by a flood protection project in Austria's westernmost federal state, namely the Ill flood protection project (Ill - Walgau water association). The question of whether the project itself is subject to an EIA was already being discussed in 2014. The application for an EIA procedure was then submitted in 2021 and the project was announced in August 2024. It remains to be seen whether the NGOs and citizens' initiatives, which have vehemently spoken out in favor of the project being subject to an EIA in the light of nature conservation, will also take the same vehement stance in the EIA approval procedure itself.

Particularly in the case of such large infrastructure projects as flood protection measures, the problem of conflicting interests and, in particular, the potential for conflict between the public interest in flood protection on the one hand and nature and species protection on the other, becomes apparent in approval procedures and usually also beforehand. This was tragically demonstrated in the area of the Perschling in the Tullnerfeld, where a dam renovation project has been under discussion for several years, but the renovation was delayed due to the presence of the protected Danube barge snail and the dam broke last week.

A Danube Island 2.0 could therefore certainly no longer be completed within this timeframe in 2024.

Renaturation versus flood protection

The so-called EU Restoration Regulation has no legal influence per se on the approval of flood protection projects and does not result in existing flood protection projects having to be restored. This is due to the fact that the member states are obliged to primarily remove artificial obstacles that are no longer needed for certain purposes, such as flood protection.

Unfortunately, the last few days have impressively demonstrated that the Danube Island itself is still needed for flood protection.

However, the situation is different and more complex when it comes to the question of approving new flood protection projects and how such flood protection projects are designed. In this respect, there may very well be potential for legal conflict, depending on the specific design of the flood protection project itself. This is due to the fact that flood protection will not only be possible with renaturation, but that technical structures will also be required. It will be up to the federal states in particular to take special care when designing the EU restoration regulation in the restoration plans.

Conclusion

A Danube Island 2.0 as flood protection would also be feasible today, even if the legal approval rules have changed significantly and the approval procedures and potential conflicts of conflicting interests have become more complex as a result. Overall, when planning flood protection projects, in addition to the actual purpose of flood protection, other ecological aspects and issues of renaturation must be taken into account in order for a project to be successfully implemented.