Construction was launched by Dr Rüdiger Grube, chairman of German Rail (DB), in the presence of Mr Alexander Dobrindt, federal minister of transport and digital infrastructure (BMVI), Mr Winfried Hermann, minister of transport of Baden-Württemberg, Mr Edgar Schömig board member of Züblin, and around 500 guests.

Rastatt tunnel will run from the northern portal at Ötigheim, and pass beneath Rastatt to resurface at Rastatt-Niederbühl and is the centrepiece of Section 1 (Karlsruhe - Rastatt-South) of the project.

The two tunnel boring machines will operate simultaneously. Fitting out the tunnel with slab track and control and safety systems will start in 2019, and commissioning is planned in 2022.

This will be the first DB Network project to use the BMVI-funded Building Information Modelling (BIM) system, and the Rastatt Tunnel is the largest of four national pilot projects in which the potential of this new digital working method is being tested.

With BIM, planning, flow and use of the tunnel are simulated in three dimensions. Stakeholders and disadvantaged people receive a realistic picture of the plans as early as possible. In addition to the geometric information, schedules and costs flow into the model. As a result, construction and cost trends can be simulated in advance to enable a quick response to cost increases.

The overall project involves rebuilding the double-track railway as a four-track main line to create additional capacity, especially for freight, but also for long-distance passenger services. Sections 2 to 6 (Rastatt South - Offenburg) and Section 9.1 (Schliengen - Eimeldingen) are already in operation.

Due to a decision by the Project Advisory Board and the Bundestag regarding the additional costs for optimising section 7 (Offenburg - Herbolzheim) the plans for this section are being re-drafted. Section 8 (Herbolzheim - Hügelsheim) is going through the planning approval phase, while some elements, such as subways and noise barriers, of Section 9 (Haltingen - Weil am Rhein) have already been completed.