The high-speed Lyon-Turin rail link involves excavating what will be the world's longest rail tunnel, but will its carbon footprint be too damaging?
The first of seven giant tunnel-boring machines was assembled at a German factory two weeks ago and, once they are all put into action in a year's time, they will greatly speed up excavation through the base of Mont Cenis in Savoie, France.
Meanwhile, work is also continuing with the use of more traditional machinery to cut through 500 metres or so of the rock each day.
Construction workers for the state-owned Tunnel Euralpin Lyon Turin company (TELT) need to excavate enough rock to create two 57.5 km long tunnels - longer than the Channel tunnel by six kilometres.
By the time it is finally finished in 2032, it will mean fewer trucks and more trains on both sides of the border - if it is finished on time. The project has suffered many delays, mostly involving financing setbacks over the years.
But will it still be viewed as beneficial to the environment, as it was in the 1990s when it is finally finished in 2032?
Stéphane Guggino, the General Delegate of La Transalpine Lyon-Turin, supports the project:
"The urgency is, there are three million trucks passing between France and Italy every year. If you don't dig tunnels, you keep the trucks on the roads."
But drilling a tunnel on the French-Italian border is threatening water resources, which are under strain more than ever before, according to environmentalists.
Alberto Poggio from the Mountain Union of Val de Suse's Technical Commission told Euronews the data speaks for itself:
"We have calculated that the construction of the entire Turin-Lyon line will result in a net contribution of 10 million tonnes of carbon dioxide into the atmosphere. Estimates indicate that 600 to 1,000 litres of water per second of water will be discharged from the tunnels during the work.
"It's a bit like a large part of Turin or a large part of Lyon running out of water."
Will the TGV Lyon-Turin have a positive impact on CO2 emissions?
According to the TELT project website, "The Mont Cenis base tunnel is a priority intervention in the context of the Green Deal's decarbonisation objectives."
Reducing emissions is said to be at the heart of the project which has two main aims:
- To encourage rail travel by halving journey times between Lyon and Turin.
- To encourage the transfer of 25 million tonnes of freight from road to rail every year.
This is a major challenge, given that freight accounts for 80% of traffic on the line.
At present, it takes around seven hours to reach Milan from Paris by train. With the future high-speed line, it would take two hours less.
At this point, it's starting to become attractive for travellers to take the train rather than the plane," said Stéphane Guggino. At present, the Paris-Milan air route, a journey of 1h 30 minutes, is used by over 50,000 passengers a month.
The project's promoters also believe that fast, reliable and efficient infrastructure will be an incentive for freight carriers. The aim is to transfer almost half of all traffic from road to rail.
Construction of the Lyon-Turin track will emit around 10 million tonnes of CO2, which TELT insists will be offset after the line has been in use for 15 years. After that TELS maintains, that thanks to the transfer of goods from road to rail, the infrastructure should produce results in terms of CO2 reduction.
Over 120 years of its use, the new line is expected to save one million tonnes of CO2 equivalent per year.
These figures were revised upwards in 2020 by a report from the European Court of Auditors, which estimates that it would take a minimum of 25 years - and perhaps even 50 years if the line is under-used - to offset the emissions linked to construction.
This estimate has been called into question by Transalpine, which criticised the report's author, Yves Crozet, economist and president of the Union Routière de France think tank, for his lack of neutrality towards the Lyon-Turin project.
For the environmentalists opposed to the project, the environmental cost of the line outweighs its usefulness in the context of the climate crisis.
"We think we're going to solve problems by replacing old technologies with new ones. But our planetary limits no longer allow all that," says Green MEP Gwendoline Delbos-Corfield. "It's also a question of reducing, being sober and no longer building useless things because their very construction causes environmental damage".
2. Why not use the existing rail line?
The question of how to use the existing rail line is central to the debate on the Lyon-Turin TGV.
A line linking Lyon and Turin already exists. It passes through a historic 14-kilometre-long tunnel on Mont Cenis. Dug in 1871, the tunnel was renovated in 2012 to facilitate the transport of goods. It's completely modernised. It only needs a few improvements, and it would cost much less to make them than to dig new tunnels," said Philippe Delhomme, Co-President of the Vivre et Agir en Maurienne Association.
According to the project's opponents, this "historic line" is under-used. NGO Les Amis de la Terre, the Vivre et Agir en Maurienne Association and the La France party have argued that the existing line would be "capable of ensuring a massive modal shift of 16 million tonnes per year, equivalent to the weight transported by one million heavy goods vehicles" - the target set by TELT.
However, it argues 162 freight trains will be able to pass through the new tunnel every day, compared with the 50 or so that currently travel daily on the existing line.
3. What impact will the project have on water resources?
The drying up of water resources is the most divisive aspect of this project.
One of the main challenges is the limited availability of this vital resource in the regions crossed by the project. In fact, the areas affected by the construction project are already experiencing a reduction in the flow of water as a result of climate change.
On the one hand, a project of this scale is extremely water-intensive. The construction of tunnels and railroads requires large quantities of water for earthworks, concreting and washing materials. This demand has a significant impact on existing reserves, further jeopardising the water supply of local communities and the surrounding ecosystem.
"But the water needed to build the tunnel is derisory compared to the amount of water wasted due to the interception of natural resources during excavation operations", explained Alberto Poggio, an engineer and member of the Technical Commission of the Montana Union of Val di Susa.
The greatest danger is excavation. By drilling in the mountains, we risk drawing on natural water reservoirs. In a 2021 report, TELT confirmed that some of these resources were under threat. The water extracted would not be used in the work but would be taken out through the galleries to avoid flooding.
4. How will the landscape be affected?
The Alpine landscape that crosses the French-Italian border is already visibly affected. "In the Val di Susa, quality of life has become problematic from several points of view," explains Alberto Poggio. "The presence of construction sites is starting to become a nuisance, from the point of view of materials and for the environmental impact noted by controls which are rather small but, are starting to indicate criticalities", continued the expert.
According to the engineer, the landscape is also compromised by the presence of landfill sites where the materials used on the sites are stored: "When I do an excavation, what comes out, the crushed rock, has to be permanently disposed of. Part of this elimination has been achieved by dumping the material in identified areas of the same valley. This has already happened in the Maurienne and also at the Maddalena di Chiomonte site, where an auxiliary tunnel was dug and the waste used was dumped alongside it on a permanent basis".
It's the same scenario in France: "Meadows have been gutted, forests have already been razed to store future waste", explains Philippe Delhomme. "Small villages are seeing more trucks transporting waste or goods, and are obviously upset by the dust, the noise... As the crow flies, I'm 1.4 kilometres from a waste disposal site. Well, I can hear the trucks, I can hear the noise of the machines. It's no longer possible to accept this today."
And farmland is at risk too. "We're in a Beaufort zone which stipulates that 70% of the fodder needed to make this cheese for livestock is indispensable, and it can only be indispensable if the meadows are irrigated. But with less water, irrigation won't be possible", commented Philippe Delhomme.
But for TELT and its supporters, these are issues that need to be put into perspective.
“When you build infrastructure, there is always an ecological impact, that's obvious. It is a reality, Stéphane Guggino said. "But these ecological impacts must be measured against the ecological benefits, over the very long term and from this point of view, it is always positive.”