BLS has placed plans for the full double-track expansion of Switzerland’s 35km-long Lötschberg Base Tunnel on public display, ahead of the start of major construction works currently scheduled for 2028.
The US$2.1bn project will complete the second bore of the Lötschberg Base Tunnel between Frutigen and Raron, removing the remaining single-track bottleneck on one of Switzerland’s principal north-south rail corridors.
Plans for the revised construction project are open for public consultation from 17 August to 15 September 2026. Approval has already been granted for a partial expansion of the base tunnel, meaning the latest consultation covers only those changes required to deliver the full double-track scheme.
Most of the previously approved infrastructure, construction sites and environmental protection measures will remain unchanged, with the additional work for the full expansion largely taking place underground.
The most significant element will be excavation of the second bore over the remaining 7km section between Mitholz and the northern portal at Frutigen. An additional emergency stopping point will also be constructed in the Mitholz area, while the construction sequence and logistics have been revised to accommodate the full expansion.
The 35km Lötschberg Base Tunnel currently has a mixture of single- and double-track operation. Between Raron and Ferden, trains use two fully equipped bores over approximately 14km.
Between Ferden and Mitholz, a second 14km-long bore has already been excavated to its basic structural profile but has yet to be fitted with track, power supply and safety systems.
Over the final 7km between Mitholz and Frutigen, however, the second tunnel bore still has to be excavated. Completing and equipping these sections will allow trains to use two tracks throughout the entire base tunnel.
BLS said eliminating the existing bottleneck would provide additional capacity and improve the resilience of rail services on the north-south axis. It will enable a continuous half-hourly long-distance passenger service between Bern and Valais while also creating additional paths for freight traffic.
The Lötschberg Base Tunnel forms a central part of Switzerland’s New Rail Link through the Alps (NRLA/NEAT) programme. It opened to commercial traffic in 2007 but was initially completed with only part of the planned second bore fully equipped because of funding constraints.
Under the current programme, main construction works are scheduled to begin in 2028, with the overall project expected to take around 10 years to complete.
Once finished, the project will complete the original double-track concept for the Lötschberg Base Tunnel and substantially increase capacity on the Alpine rail corridor.
Comments:
Facts Only
* BLS has placed plans for the full double-track expansion of Switzerland’s 35km Lötschberg Base Tunnel on public display.
* Major construction works are currently scheduled to start in 2028.
* The US$2.1 billion project will complete the second bore of the Lötschberg Base Tunnel between Frutigen and Raron.
* This action removes a single-track bottleneck on one of Switzerland’s principal north-south rail corridors.
* Plans for the revised construction project are open for public consultation from August 17 to September 15, 2026.
* Approval has been granted for a partial expansion of the base tunnel.
* Most previously approved infrastructure and environmental protection measures will remain unchanged.
* The most significant work involves excavating the second bore over the remaining 7km section between Mitholz and the northern portal at Frutigen.
* An additional emergency stopping point will be constructed in the Mitholz area.
* The project is scheduled to take around 10 years to complete.
Executive Summary
Plans for the full double-track expansion of Switzerland’s 35km-long Lötschberg Base Tunnel are on public display ahead of major construction starting in 2028. This US$2.1 billion project aims to complete the second bore of the tunnel between Frutigen and Raron, eliminating a single-track bottleneck on a key north-south rail corridor. The consultation period for the revised construction project runs from August 17 to September 15, 2026, though approval for a partial expansion has already been granted. Most existing infrastructure, construction sites, and environmental measures are expected to remain unchanged, with the expansion primarily occurring underground.
The most significant physical work involves excavating the second bore over the remaining 7km section between Mitholz and the northern portal at Frutigen. An additional emergency stopping point will be constructed in the Mitholz area, and construction logistics have been revised accordingly. This upgrade is projected to increase capacity, enabling a continuous half-hourly long-distance passenger service between Bern and Valais and creating new freight paths. The project is part of Switzerland’s New Rail Link through the Alps (NRLA/NEAT) programme and is expected to take approximately ten years to complete, resulting in a completed double-track concept for the tunnel.
Full Take
The narrative presents a clear trajectory toward infrastructure modernization driven by capacity enhancement on a critical alpine rail corridor. The framing emphasizes the transition from a constrained system (single-track bottleneck) to an optimized one, positioning the project within a larger strategic framework like NRLA/NEAT. The implication is that large-scale public works are necessary to achieve systemic resilience and economic flow for regional connectivity.
The pattern observed is the strategic deployment of transparency—placing plans on display prior to detailed action—to manage the complex public acceptance required for massive, long-term engineering projects. This procedural step frames the subsequent, concrete actions as inevitable outcomes of a consultation process, rather than arbitrary decisions. The tension lies between the promise of enhanced capacity and the localized impacts inherent in altering established infrastructure corridors, particularly regarding excavation and local logistics.
What is unstated is the cost-benefit calculus related to shifting freight versus passenger priority within this expanded capacity. Who bears the burden of the planned modifications, especially concerning environmental protection measures that remain largely unchanged while physical alterations occur underground? Furthermore, how does the political necessity driving the NRLA/NEAT program interact with the local demands communicated during the 2026 consultation period to ensure that regional concerns are fully integrated beyond the physical execution schedule?