Croatia Plans to Restore a Danube Side Channel to Protect Floodplain Ecosystems

Near the Croatian village of Draž, a project is being prepared to restore the hydrological connection between a disconnected side channel and the main course of the Danube River. The initiative is part of the Horizon Europe DaWetRest project, aimed at restoring wetlands and improving the ecological connectivity of Danube floodplains.

Before hydrotechnical works begin, an international research team conducted a comprehensive survey of vegetation in riparian forests and aquatic ecosystems. The findings were published in the scientific journal Biodiversity Data Journal.

The study covered 20 sampling locations, documenting 72 plant taxa, 251 taxon occurrence records, and 331 environmental and vegetation measurements. Researchers examined plant species composition, water quality parameters, flow conditions, and the presence of invasive species.

The collected data will provide a scientific baseline for assessing ecological changes following the reconnection of the Danube side channel. This will help determine how restored hydrological connectivity affects biodiversity, floodplain forests, and aquatic plant communities.

The study area is located within the transboundary Middle Danube floodplain, part of the UNESCO Mura-Drava-Danube Biosphere Reserve, one of Europe's most significant natural ecosystems.

Commentary by the Institute of Danube Research

The Institute of Danube Research (IDR) emphasizes that the Croatian project demonstrates the importance of a scientifically grounded approach to river ecosystem restoration.

Restoring natural connections between the Danube's main channel and its side branches is strategically important for biodiversity conservation, maintaining floodplain water balance, and strengthening ecosystem resilience to climate change. Equally important is the systematic scientific monitoring accompanying such projects, which makes it possible to assess their actual environmental effectiveness.

According to the Institute, Croatia's experience could be valuable for the Ukrainian section of the Lower Danube, particularly in developing programmes to restore floodplain habitats, natural water exchange, and wetlands.

At the same time, restoring hydrological connectivity requires careful monitoring of invasive species and consideration of nature conservation, navigation, and water management interests.

The IDR stresses that ecological restoration of the Danube should become a priority of cross-border cooperation among Danube countries, integrating environmental protection, scientific monitoring, and sustainable water resources management.