Work has begun on the 5.8km southern section of the Brenner Base Tunnel, with excavation work from the Isarco Consortium, led by Salini Impregilo with Strabag, Collini Lavori and Consorzio Integra as partners.
The railway tunnel starts at Fortezza, Italy, before going under the Isarco River.
The southern section is part of the 55km Brenner tunnel that will eventually link Fortezza with Innsbruck in Austria.
The work, valued at about €301 million, is expected to be finished in 70 months, while completion of the entire Brenner tunnel is expected by 2025.
Salini Impregilo said the construction of the southern section was technically complex. The section will go under the Isarco River with four 60m tunnels, using liquid nitrogen to freeze the earth, rock and detritus between the tunnels and the riverbed, making the ground waterproof.
The company added that the passage under the river was only a part of the complex project that had been 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 achieved without hampering local traffic.
Salini Impregilo, along with Strabag, also obtained the Tufles-Pfons lot worth €377 million – the final section of 37km that leads to Innsbruck.
High-speed passenger trains will travel through the Brenner tunnel at speeds of up to 250km/h, and there will be cargo trains as well, making it a strategic trade link between Italy and the rest of Europe.
Once completed and connected to the railway ring in Innsbruck, it will be the longest underground railway in the world at 67km.
The Brenner Base Tunnel is considered by the European Union as a strategic part of the Trans-European Transport Network (TEN-T), liking Verona in Italy with Munich, Germany.