Implenia-led joint venture awarded $478 million Swiss tunnel contract

It was announced on June 28 that a joint venture (JV) led by Implenia was awarded a $478 million contract regarding the construction of the “Sisikon Tunnel” in Switzerland.

Furthermore, the Sisikon Tunnel will be part of the broader “A4 Neue Axenstrasse” project, namely its lot 200.

More specifically, the tunnel is going to be a single-tube 4.4 km two-way road tunnel, which is going to be constructed in rock by means of the drill and blast method.

As for the Neue Axenstrasse road project, it broke ground in 2009 and is coming to replace the existing Axenstrasse route, which was completed between 1864 and 1865, stretching between Brunnen and Flüelen.

It is also noteworthy that the Sisikon Tunnel is going to be one of the two tunnels that will be present in the Neue Axenstrasse, with the second one being the Morschach Tunnel.

The joint venture to construct the Sisikon Tunnel consists of Implenia and Frutiger at stakes of 60% and 40% respectively, while in addition to the tunnel, the JV is also going to construct other underground structures, including access tunnels, passing places, ventilation hubs and exhaust ducts.

Other Implenia civil engineering units are also going to be occupied with various external works, including a large gallery to protect against natural hazards.

These various construction projects are going to produce some 2 million tons of excavated material, most of which will be transported by boat to the Reuss Delta in Flüelen, where it is going to be reused in a large renaturation project.

Finally, the order is currently subject to a consultation period until the end of July, while work is expected to commence in mid-2025 and be completed by 2034.