The 35 km long Lötschberg Base Tunnel is to be extended over a length of 14 km between Ferden and Mitholz according to the will of the Swiss parliament. This would provide 28 km of double-track access and only 7 km of single-track access. The plans for this partial expansion have been available to the public since August 17, 2020. The public disclosure is the next step in the planning approval process led by the Federal Office of Transport. The Swiss railway company BLS AG is also continuing to work on the plans for the complete conversion to two tunnel tubes so that these plans will be available by the end of 2022 at a comparable level to that of the partial conversion.
Full Extension To Be Reviewed Again
In order to connect the new tunnel section at Mitholz to the existing single-track section during the partial extension, extensive construction work is required on the existing tube. For this, the tunnel must be closed for eight months. Because of this long closure, the Swiss parliament has instructed the Federal Council to review the complete development of the tunnel, which would be possible without a long total closure. The Federal Council will submit the results to Parliament as part of the interim report on the STEP expansion step 2035.
On this basis, parliament will decide, probably at the beginning of 2023, whether it wishes to adhere to the partial expansion already decided upon or whether the tunnel should be fully developed. BLS is therefore waiting until then to put out a tender for the main work for the partial development. From 2022 on, however, it will carry out certain preparatory work that will be necessary for both the partial and the full extension.
Closure for Partial Expansion: Capacity on the Lötschberg Mountain Line Is Sufficient
If parliament decides in favor of the partial expansion, construction work is expected to begin in 2025 and last until the end of 2031. The eight-month closure is scheduled for the end of the construction period. During this period, the long-distance trains will run over the mountain line. Freight trains will be diverted via the mountain route or the Gotthard axis. The capacities of the car transport and RegioExpress trains through the Lötschberg summit tunnel will remain unchanged. If the tunnel is fully expanded, a corresponding project amendment is expected to be published in mid 2023. In this case, construction work will last from 2026 to the end of 2033.