Ground-breaking ceremony with toy excavators on Lake Constance

On 11 July 2024, a symbolic ceremony marked the start of work on the construction of the 970-metre-long Röhrenberg Tunnel, which is being built as a noise protection measure as part of the upgrading and extension of the B33 between Allensbach and Konstanz.

This time, it was not the ministers and mayors who, together with the contractors Storz and Eiffage Infra-Süd, took up the shovels for the ground-breaking ceremony; instead, the toy diggers operated by local nursery children were allowed to roll up and begin the initial earthworks.

Both road users and residents of the Lake Constance region will benefit from the construction of the Röhrenberg Tunnel. Climate-friendly construction is also a key focus in this holiday region, for example through the use of a special floor covering.

The tunnel will be constructed using the open-cut method with two tubes and will be flanked on both sides by 30-metre-long portal structures. The structural work is due to be completed by mid-2028, so that, once the operational systems have been installed, traffic is expected to flow from autumn 2029.

The tunnel forms part of an overall project to construct and upgrade the B33 between Allensbach and Konstanz over a distance of 10.6 kilometres. The entire project is due to be completed by 2035.