The Gotthard Base Tunnel is one of the most impressive engineering projects constructed in the 21st century. It took 17 years to construct the 56-kilometre tunnel through the Alps between Erstfeld and Bodio, Switzerland. The tunnel, the world’s longest and deepest, serves as a vital rail link between Northern and Southern Europe.
But after nearly a year of restoration works after a freight train derailment, the Gotthard Base Tunnel will reopen on September 2, 2024, with freight and passenger services set to resume.
But what happened on that fateful day in August 2023?
According to Swiss Federal Railways (SBB), an SBB Cargo train was hauling 30 freight cars from Italy northward through the Gotthard Base Tunnel. The cars were successfully inspected in Chiasso, a town just on the Swiss side of the border with Italy. Besides a jammed brake that was corrected in a subsequent inspection in Bellinzona, the freight train entered the tunnel in working condition. However, the 16 freight cars derailed inside the Gotthard Base Tunnel.
The Swiss Transportation Safety Investigation Board believes that a broken wheel caused the derailment. Wheel disc fragments indicate that the train carried on for a few kilometres with a broken wheel before ultimately derailing. The cars destroyed the tracks while scattering wine, lemonade and other goods along the tunnel.
In a statement, SBB has revealed how massive the repair project will be:
“Extensive investigations have revealed that the scale of the damage is considerably greater than initial assessments suggested. In total, around 8 kilometers of track and 20,000 concrete sleepers need to be replaced. The track bed is severely damaged in the area of the Faido cross-over. It will take several months to replace all the damaged components of the railway installations. SBB currently assumes that both tunnel tubes will be available for limited rail traffic at the beginning of 2024.”
While the eight kilometres of track are replaced, only one of the Gotthard Base Tunnel’s two tubes will be operational. The single tube will be dedicated to freight traffic. Passenger trains will now take a “panorama” detour to use SBB’s words. The detour added between an hour to two hours to trips over the Alps and required most passengers to switch trains to complete their journey.
This story has been updated since it was published.