On April 1, 2024, at the Saint-Martin-la-Porte construction site (CO7), the red Savoy tunnel boring machine (TBM) Viviana was officially launched. This marks the beginning of excavation for the Turin-Lyon base tunnel using TBMs. Viviana is the first of seven TBMs that will operate over the next three years. The machine's name honors Mario Virano’s wife, recognizing her role in fostering Italian-French dialogue on the project.
TBM Viviana: A Powerful Machine
- Length: 180 meters
- Diameter: 10.4 meters
- Weight: 2,300 tons
- Power: 8,100 kilowatts
- Excavation Distance: 9 km of the northern tunnel tube
Viviana will excavate a 9 km section of the northern tunnel, running parallel to the segment previously dug by TBM Federica.
Other Ongoing Excavations
Meanwhile, traditional excavation methods continue for:
- The main tunnel toward Saint-Julien-Montdenis
- Additional tunnels and technical caverns in La Praz (CO6)
By the end of January, excavation of the tunnel entrance at Saint-Julien-Montdenis (CO8) had progressed 3 km—about 1.5 km per tube—using controlled explosive techniques.
In January, the CO5 construction site in Modane was officially handed over to the ELYOT consortium (Eiffage Génie Civil, Spie Batignolles, Ghella, and Cogeis). This team is responsible for constructing the 22 km tunnel section connecting:
- The Villarodin-Bourget/Modane shaft
- The Clarea site in Italy
- Toward Italy: Two TBMs
- Toward France: Traditional methods (demolition hammers and/or explosives)
This section will also feature safety infrastructure, including emergency exits every 333 meters, niches, and transverse tunnels.
Additional Key Construction Sites
- Avrieux (CO5a): The LYTO consortium (VINCI Construction, WeBuild, Master Drilling Europe, and others) continues work on four ventilation shafts.
- Saint-Julien-Montdenis (CO11): The GEME consortium (EUROVIA agent) is developing a materials treatment station to process excavated materials.
- Chiomonte & Giaglione (CO3/4): Environmental studies are underway at the launch site for a TBM recently ordered by the UXT consortium.
- Chiomonte (CO4c): In collaboration with SITAF, work continues on the A32 motorway junction, with:
- 50% of the exit ramp slab completed
- Final three piers of the entry ramp under construction
- San Didero (CO-02c): Technical building construction is progressing, including:
- A Command and Control Post
- A new truck parking area for heavy vehicles
- Motorway overpass ramps
- Salbertrand (CO10): Environmental monitoring and surface war reclamation efforts continue in preparation for processing tunnel excavation materials.
The Turin-Lyon base tunnel project is advancing steadily, with TBM Viviana’s launch marking a major milestone in the excavation process. As additional TBMs are deployed and construction progresses across multiple sites, the project remains on track for completion according to schedule.
