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Construction sites

Saint Martin de la Porte
Saint Martin de la Porte

12 construction sites between France and Italy: 9 are civil engineering works and 3 related activities

Active or completed construction sites
The base tunnel

The construction sites for the Lyon-Turin base tunnel are active in the two countries. The base tunnel, the main work for the cross-border section, is a complex infrastructure, consisting of: two parallel, 57.5-km-long, tubes to accommodate the tracks for the passage of freight and passenger trains; 204 safety bypasses and 4 declines.

In addition to the underground work, TELT manages and coordinates the surface sites, both in Italy and France, which ensure the connection to the respective national lines through the new international stations.

The construction sites are checked around the clock via a series of internal and external monitoring stations that measure 135 different environmental parameters (water, dust, asbestos, radon, etc.). These measurements are carried out under the supervision of national control bodies, to ensure the respect of the territory and the health of workers and citizens.


Progress: may 2024

36,6 Km dug
Digging and constructions 22.3%
Travailleirs descenderie villarodin bourget modane_IMG_0948_Copyright_Caroline_MOUREAUX_VBM
The access adits

The access adits are three on the French side – Villarodin-Bourget/Modane, La Praz and Saint-Martin-La-Porte – and one is in Chiomonte on the Italian side; in total, the access adits constitute approximately 18 km of tunnels that will be used both for the construction and maintenance of the base tunnel and as emergency accesses.

More specifically, the access adits have represented 4 different ways to ascertain and evaluate the main geological obstacles and to develop the most efficient solutions for the construction of the base tunnel: the re-use of excavation materials at the Villarodin-Bourget/Modane construction site; water management in tunnels at La Praz; rock convergence at Saint-Martin-la-Porte; and mechanised excavation at Chiomonte.

In this phase, the access adits serve as access routes to the base tunnel construction site. Once the tunnel is operational, they will serve as maintenance access tunnels and as safety accesses.

The stations

The project for the cross-border section of the Lyon-Turin line includes two international stations, located each a few kilometres outside the base tunnel. In Saint-Jean-de-Maurienne, France, and in Susa, Italy, the two newly designed facilities will be able to handle multimodal exchanges (the switch from one transportation system to another, for example from road to rail), to accommodate varying passenger profiles, each with specific service requirements (parking spaces for various means of transportation, such as cars, bicycles, buses), and to handle the connection with local transport networks in the two reference regions.

The international stations put the Olympic mountains of the Susa Valley and the French Alps’ “Domain Skiable” ski area on the TEN-T primary network, just a few hours away from most European capitals.

The projects are designed to blend in as much as possible with the surrounding natural and built-up landscape and to constitute the interchange nodes between the international line and the local networks.

Kengo Kuma

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