The Gotthard axis is to be extended to become a 4 metre corridor, so that in future semi-trailers with a corresponding 4-m corner height can also be transported. This will assist freight traffic crossing the Alps to be relocated from road to rail. The biggest part-project of this scheme is to replace the existing 2.16 km long, two-track Bözberg Tunnel in the Canton of Aargau with a new 2.6 km long tunnel also possessing two tracks. The main job was awarded by the SBB to Implenia in July. The contract is worth some 145 million Swiss francs.
The new tunnel’s northern portal is located at Effingen and the southern portal at Schinznach-Dorf. The main drive will take place from the southern portal using a tunnel boring machine. The tunnel muck will also be removed from a rail loading station set up there – in order to avoid the need for almost 57 000 lorry loads of material being carried via the cantonal roads. Building is scheduled to start in spring 2016 and the tunnel is intended to open in 2020 following a construction period of around four years. Apart from the track, the contract also includes the rail technology. In addition, the existing, two-track tunnel, which is not capable of accommodating a 4-m corner height, will be converted into a service and rescue tunnel with five cross-passages leading from the new to the old tunnel. The redevelopment scheme is scheduled to be completed by late 2022. G. B.