Planning for the upgrade of the Lötschberg Base Tunnel is entering the next stage

In accordance with the will of the Swiss parliament, the railway infrastructure of the 35-kilometre Lötschberg Base Tunnel is to be upgraded along a length of 14 kilometres between Ferden and Mitholz. This would mean that the tunnel would have dual tracks along 28 kilometres of its length, with only 7 kilometres of single track remaining. The plans for this partial upgrade will become the subject of a public consultation from Monday 17 August 2020. This public consultation is the next stage in the planning-approval process overseen by the Federal Office of Transport. BLS is also working on the plans for the full upgrade to two tunnel bores, so that these plans will be available by late 2020 at a similar level of planning maturity to those for the partial upgrade.

The full upgrade is being reviewed again due to an eight-month closure

In order to connect the new tunnel section to the existing single-track section at Mitholz, major construction work is required on the existing bore. For this purpose, the tunnel must be closed for eight months. Owing to this lengthy closure, parliament has commissioned the Federal Council to once more review the full upgrade of the tunnel, which doesn’t require a lengthy total closure. The Federal Council will share its findings with parliament as part of its interim report on STEP ES 2035.

On this basis, parliament is scheduled to decide by early 2023 whether it wishes to adhere to the previously approved partial upgrade or whether the tunnel should be fully upgraded. For this reason, BLS is waiting until then before issuing its invitation to tender for the primary construction work on the partial upgrade. Instead, from 2022 onwards the company will already conduct certain preparatory tasks required for both the partial upgrade and full upgrade.

Sufficient capacity on the Lötschberg mountain line during the closure period

If parliament opts for the partial upgrade, construction work is scheduled to start in 2025 and last until late-2031. The eight-month closure is planned to occur towards the end of the construction period. During this closure period, long-distance trains will operate via the mountain line. Freight trains will be re-routed via the mountain line or the Gotthard axis. The capacity of the Car Transport service and RegioExpress trains through the Lötschberg Summit Tunnel will remain unchanged. In the event that a full upgrade is chosen, the requisite project amendments are scheduled for public consultation in mid-2023. In this case, construction work would last from 2026 until late-2033.

BLS deems a direct full upgrade to be the best option

Moving directly to the full upgrade is deemed by BLS to be the best option, as it doesn't require a complete closure of the Base Tunnel. This avoids any negative economic impact and costs tax-payers less in the long term than a phased full upgrade. This approach would also result in increased flexibility in timetable planning and greater stability in terms of the services on this important NRLA axis.