Lyon Turin High Speed Railway – Mont Cenis Base Tunnel | CO3-4 Chiomonte / Susa

The Lyon-Turin link consists of a new railway line for both passenger and freight transport extending over 270 km, of which 70% will be in France and 30% in Italy. It will form the central link of the Mediterranean Corridor, one of 
the nine corridors of the Trans-European Transport Network (TEN-T). The cross-border section, delivered by TELT the Franco-Italian project company TELT, constitutes the core component of the project and will connect the 65 km stretch between the two international stations to be built at Saint-Jean-de-Maurienne (France) and Susa (Italy), where the tracks will connect to the existing rail network. The principal element of the cross-border section is the Mont Cenis Base Tunnel, comprising two single-track tubes extending for 57.5 km, of which 45 km are in 
France and 12.5 km in Italy.  Once completed, the tunnel will rival the Brenner Base Tunnel — also under construction by Ghella — as one of the longest railway tunnels in the world. The tunnel will transform the existing 
mountain railway line, which currently passes through the historic Fréjus railway tunnel at an altitude of 1,300 metres, into a low-gradient railway route, improving the competitiveness and safety standards of rail transport while reducing energy consumption.

CO3-4
Chiomonte / Susa, Italy 
The contract covers the construction of the base tunnel on the Italian side, starting from the existing construction site in the Maddalena area of Chiomonte and extending to the Susa portal, involving a total excavation length of 28.5 km. The first TBM will excavate the southern tube of the base tunnel and the Maddalena 2 access adit, from which the second TBM will subsequently be launched. The works comprise the connecting bypasses, the interconnection tunnels between the two tubes, the Clarea safety site and the cut-and-cover tunnel at the eastern entrance to Susa.On the official launch date of the Chiomonte construction site (18 December 2023), Ghella, 
together with the other project partners (lead contractor Itinera and Spie Batignolles), signed the “Integrity and Sustainability Pact” for companies involved in the Lyon-Turin project, and the “Mission-S Charter”, the programme governing occupational health and safety across the project’s construction sites. Through these two agreements, TELT requires all companies within the supply chain to adhere to commitments based on the fundamental principles of the United Nations Global Compact. TELT has committed to making the Chiomonte site a “zero-emissions construction site”. To achieve this objective, it has adopted a strategy focused on minimising emissions using energy from renewable sources, low-energy-consumption technologies and low-emission vehicles, including electric vehicles. At the same time, it is committed to offsetting residual emissions through certified carbon reduction projects, giving preference to initiatives located close to the construction site. 

Benefits

1. Improved safety standards, reduced energy consumption and shorter journey times compared with the existing rail connection.
2. Modal shift from road to rail equivalent to approximately one million lorry journeys per year.
3. Reduction in greenhouse gas emissions of approximately 1 million tCO₂eq per year once the infrastructure is fully operational.