Bypass channel in Ludwigsburg

The city of Ludwigsburg implemented the IKoNE pilot project "Zugwiesen" in the area of the Neckar barrage Poppenweiler in cooperation with the Water and Shipping Authority Stuttgart. The overall measure consists of two fundamentally different functional areas, which belong to the absolute lack biotopes at the developed Neckar. On the one hand, a 1.7 km long bypass channel was created, which both overcomes the ecological barrier of the barrage and provides new habitats and reproduction areas for typical flowing water species. On the other hand, a newly created, richly structured, approx. 38,000 m² side watercourse creates the necessary stillwater habitat for stagnophilic and floodplain-typical aquatic organisms. This water body is connected to the Neckar River by a large, differently zoned opening, so that an unimpeded exchange of all species, including bottom-oriented species, is possible at all times.
Due to the location in the conurbation with a high recreational pressure, an infrastructure with "visitor magnets" (footbridges, island with observation tower) was created in order to meet the interest of people in the newly created Neckar landscape and to be able to direct them in a targeted manner.

Bypass channel:
To enable the fish "barbel, nose, hazel and co" to overcome the 7 m height difference at the Poppenweiler barrage, more than just a technical "fish staircase" is required. Along the entire Zugwiesen project, a 1.7 km long flowing channel was found, which not only enables fish to ascend, but is itself an independent flowing water habitat; a lacking biotope on the navigable Neckar. The steeper flow section with a height difference of 5 m was designed as a bottom channel with a rye channel basin structure.

Lateral waters:
Begrading and damming of the Neckar have led to the almost complete loss of adjacent floodplain biotopes together with their species inventory. In order to provide new habitat for stillwater species, richly structured side waters have been constructed which have large areas of contact with the Neckar. In the Zugwiesen, 3.8 hectares of new stillwater areas with a depth of up to 2.8 m were created, with differentiated design of the bed and slopes. The banks are partly planted, sown or left to succession. Biological engineering structures help to reduce the ship-induced water level fluctuations so that pike, tench and other cyprinids have optimal breeding conditions. Thanks to the exemplary cooperation with the Stuttgart Waterways and Shipping Authority, which implemented bank restoration measures in the relevant section at the same time, it was possible to completely remove the flood embankment in the area of the new side watercourse and to create an effective aquatic network of the new habitat with the Neckar.
In addition to these replacement habitats for fish, which are connected to the Neckar, amphibians are also provided for. Numerous water areas of varying size, depth, structure and continuity provide habitats ranging from puddles to pools to small lake biotopes. The protected and inaccessible location between the bypass channel and the Neckar River guarantees the greatest possible freedom from disturbance.

Bridge and observation tower:
A wide, curved bridge with wooden decking is both an experience and a connecting element to the visitor island. As you cross the bypass channel and side waters, you enjoy a variety of interesting views into, onto and across the water. At the end of the footbridge you reach the visitor island with the observation tower, the Stork's Nest, which gives visitors an overview and the opportunity to observe from a bird's eye view. Its name expresses the hope that storks will once again make their home here. Here the nature lover can linger, observe and realize the dimension of the floodplain biotopes in the Zugwiesen.

Construction period 1st construction phase: July 2011 - April 2012
Construction costs 1st BA: approx. 2.4 million €

Construction period 2nd construction phase: February 2013 - April 2014
Construction costs 2nd BA: approx. 3.9 million €