Brenner Tunnel: Salini Impregilo Begins Work under Isarco River

By TBM News July 14, 2016

A new step toward the construction of the Brenner Base Tunnel has been taken. An inaugural event was held July 12 to mark the beginning of work on the southern section of the railway tunnel, starting at Fortezza, Italy, before going under the Isarco River.

The 5.8-km section, part of the entire Brenner tunnel of 55 km that will eventually link Fortezza with Innsbruck in Austria, is being excavated by the Isarco Consortium led by Salini Impregilo with Strabag, Collini Lavori and Consorzio Integra as partners.

The work, valued at about €301 million ($334 million), should be finished in 70 months, while completion of the entire Brenner tunnel is expected by 2025.

The construction of the southern section is particularly significant for its technical complexity. It will go under the Isarco River with four tunnels at 60 metres each thanks to the use of liquid nitrogen to freeze the earth, rock and detritus between the tunnels and the riverbed, making the ground waterproof.

The passage under the river is only a part of this complex project that was designed with total respect for the environment. It is for this reason that one of the planned auxiliary works involves the opening of a dedicated exit on the Brenner highway so that the transportation of materials is done without hampering local traffic.

Salini Impregilo, along with Strabag, also obtained the Tufles-Pfons Lot worth €377 million ($419 million), the final section of 37 km that leads to Innsbruck.

Through the Brenner tunnel will travel high-speed passenger trains at speeds of up to 250 km per hour as well as cargo trains, making it a strategic trade link between Italy and the rest of Europe.

Once completed and connected to railway ring in Innsbruck, it will be the longest underground railway in the world at 67 km.

The Brenner Base Tunnel is considered by the European Union as a strategic part of the Trans-European Transport Network (TEN-T), uniting Verona with Munich.