The SBB is using the time between the opening of the Gotthard and the Ceneri Base Tunnels to upgrade and renew the access routes to the tunnels. This also includes the Axen route, where the track nearest the lake is to be redeveloped and upgraded. Preliminary operations started there in early October 2016. The two-way route between Brunnen and Flüelen forms an important access to the GBT. In order to ensure that the route is suitable for long-term use, the SBB was compelled to plan to renew the track nearest the lake prior to 2030; the track at the mountain side had already been comprehensively renovated in 2008/2009.
The renovation process as such for the Axen route will commence in January 2017 in three stages and is due to be completed in December 2019. Within the scope of the project, the SBB will redevelop a total of nine tunnels with an overall length of almost 6 km. Towards this end, the existing engineering structures (portals, arches, abutments and drainage systems) as well as the entire rail technology with track, cable systems and overhead wire are to be renewed. In the two longest tunnels, the self-rescue facilities will be expanded and updated. The Morschach Tunnel has been modified to cope with containers with up to 4 m corner height since the summer of 2016. This will mean that the entire Axen route will be suitable for transporting 4 m high loads. The total project is estimated to cost around 120 million Swiss francs. Once redeveloped, the Axen route will be able to fulfil its purpose for rail operations up until 2070.