A8 Interlaken-Ost – Brienz

The tunnels along this stretch have been equipped with emergency galleries in the last few years. This project was followed by a total renovation of the road surface and other engineering structures between Interlaken-Ost and Brienz. The project started in 2021 and could be finished in May 2025.

The stretch of the A8 between Interlaken-Ost and Brienz was opened to traffic in 1988 and has never undergone comprehensive renovation since then. In order to preserve the infrastructure for the future on this major route and to adapt it to the latest standards, a total renovation was carried out, starting in 2021 and lasting for four years. A few years ago, the tunnels have already been equipped with emergency galleries (putting into service 2016 & 2018). In 2020, preparatory work outside of traffic has been carried out, concerning mostly the tunnels’ control centres. Starting in 2021, the entire remaining road infrastructure was renewed. In addition, the suspended ceiling in the Giessbach tunnel was reinforced. The perimeter of the project began at kilometre 24.0, i.e. just after the Bönigen junction in the direction of Interlaken. At the other end, the perimeter ended at kilometre 37.8, i.e. in the vicinity of the Brienz junction.

Object of work

Open road

• Installation of a noise-reducing surface
• Restoration of the drainage system
• Expanding of the shoulder
• Renovation of the engineering structures

Tunnels

• Restoration of the ventilation (Completely new ventilation system in the Giessbach tunnel)
• New shoulders for the drainage system
• New surface
• Reflecting coating of the walls
• Strengthening of the suspended ceiling (Giessbach tunnel)

Traffic

The work schedule had been designed to minimise interference with traffic flow. The stretch of the A8 between Interlaken-Ost and Brienz was closed on weeknights (Mon/Tue – Fri/Sat). During daytime, the road stayed open with a reduced speed limit of 60 km/h. On certain stretches, traffic was reduced to one lane between April and November.

Details

• Handover of the stretch to traffic: 18 May 1988
• Length: 13.8 kilometres
• No. of tunnels: 3*
• Length of tunnels: Sengg, 870 metres; Chüebalm, 1,325 metres; Giessbach, 3,340 metres
• No. of bridges and other engineering structures: 38
• Duration of construction of emergency galleries: Preparatory work, autumn 2013; construction, spring 2014 until 2018
• Duration of maintenance project: 2021 – 2025 (preparatory work 2020)
• Costs for construction of emergency galleries: Approx. 100 million Swiss francs
• Costs for total renovation: Over 300 million Swiss francs

* Not included here is the Lütschinen underpass. It is also located between the Interlaken-Ost and Brienz junctions, but is allocated to the Interlaken-Ost – West stretch. Further information