The Gotthard railway, or more precisely its base tunnel, is paying the price of its own success, perhaps partly unforeseen. Brought into service in June 2016 for freight trains and extended to all other services that December, it now requires extraordinary maintenance work. Swiss Federal Railways has already scheduled a full replacement of the track system, including the rails laid on special slabs that replace the traditional ballast.
Normally, rails last at least twenty years, but the heavy passenger and especially freight traffic has shortened their lifespan. This is compounded by the fact that the number of trains running through the Gotthard has exceeded the initial forecasts. It is hardly surprising, then, that the track must be renewed earlier than average. The SBB, however, were not caught unprepared, having long since planned every stage of the operation in meticulous detail.
According to a document seen by TrasportoEuropa, in addition to an annual maintenance schedule, experimental trials were carried out in 2023 and 2024 to test specific worksite arrangements, including the possibility of laying free rails alongside an operational track with trains passing at over 160 km/h. One detail stands out: during the 49 days of testing, almost 6,700 trains passed through the selected section, carrying more than 3.6 million tonnes in total. This provided valuable insights on how best to optimise each intervention.
The results of these trials form the basis for planning the works that will cover the entire length of the base tunnel, which consists of two tubes, each 57 kilometres long, as well as all connecting and linking tracks. The complete replacement of the rails is expected to take place in phases between 2032 and 2034. The SBB has already launched a call for expressions of interest from companies capable of undertaking such a demanding project. The rail operator has not yet released official cost estimates, but investment is expected to exceed one hundred million euros.
The detailed work plan does not envisage a full closure of the Gotthard line, although managing traffic on a single alternating track will be challenging. The SBB also drew an unwelcome lesson from the derailment of a freight train in the summer of 2023 inside the base tunnel. That incident destroyed seven kilometres of track, including 20,000 sleepers and the entire underlying concrete slab, causing damage of more than 160 million euros. Traffic was completely suspended for several weeks and then only partially restored, with full regular service resuming on 2 September 2024, more than a year later.
Piermario Curti Sacchi
