New water channels in the floodplain forest preserve biodiversity and protect against flooding

Just a few meters south of the ferry road near Plittersdorf lies a natural paradise. Butterflies cross the path, swans build nests to breed in the shallow waters and there is chirping and croaking from all directions. The "Baden jungle", as the Rastatt Rheinauenwald is also known, is revealed here in all its diversity.

The nature reserve not only provides a habitat for plants and animals. It also serves as a floodplain in the event of flooding. However, for many decades, the floodplains have been increasingly silting up. This is because fine soil material is transported into the floodplain with every flood. This remains behind even after the water has long since drained away. This leads to a slow and steady rise in the floodplain.

This also affects the widely branched network of water channels, known as gullies, which are typical of the floodplain. If the deposited material is not removed during the next flood, sections of these channels silt up. What was once a continuous watercourse then becomes individual, isolated, smaller pools that threaten to disappear completely at some point.

To counteract this problem and preserve the richness of species in the floodplain forest, the city of Rastatt, together with the Institute for Landscape Ecology in Bühl, deepened a watercourse in the area between the Rhine and the Plittersdorfer Altrhein in spring 2023.
Three existing shallow waters were reconnected by a 730-metre-long low-water channel. As a result of this measure, the sediment-rich floodwater can now flow more quickly into the Old Rhine. Sedimentation of the watercourse is reduced.

The deepening of the ravine is part of the Franco-German project to renovate the Rhine promenade in Plittersdorf. The cost of the nature conservation measure is around 200,000 euros, 50 percent of which is being financed by Interreg, a joint initiative of the European Regional Development Fund. The remaining costs are shared by the town of Rastatt and the Karlsruhe Regional Council.