How long did the construction and maintenance work take?
The various tasks will be carried out in stages. The emergency galleries for the tunnels between Interlaken and Brienz and for the Simmenfluh and the Leissigen tunnel have already been completed a few years ago. Construction work for the maintenance project on the stretch between Interlaken-Ost and Brienz began in 2021 and was completed in 2025. For logistical reasons, it was not possible to simultaneously implement the maintenance project and construct the emergency galleries.
How much did the construction work interfere with traffic flow?
During construction work relating to the maintenance project on the stretch between Interlaken-Ost and Brienz, the stretch was open to traffic without interruption during the day (with reduced speed limits and parts with one lane only), but was closed at night (from 8 p.m. to 6 a.m.). During this period, traffic was diverted via the cantonal road on the right-hand side of Lake Brienz.
How much extra travel time had to be anticipated?
Due to the necessity of imposing speed limits (60 km/h) and the partial reduction to one lane during the implementation of the maintenance project, travel time on the stretch between Interlaken-Ost and Brienz increased by approximately 5 minutes. When this stretch had to be closed at night and traffic had to be diverted via the cantonal road, travel time between Interlaken and Brienz increased by around 15 to 20 minutes.
Why did stretches have to be closed at night?
In Switzerland, motorway maintenance and renovation work is planned so that its impact on road users can be kept to a minimum. The goal is that at least one lane in each direction is kept open. But the fact that there are lengthy stretches on the A8 that only comprise one lane in each direction meant that closures were unavoidable. On the stretch between Interlaken-Ost and Brienz, closures were only conducted at night, when the traffic volume is at its lowest. This solution (open during the day, closed at night) means that more than 90 percent of all road users were able to use their accustomed route and only experienced minor delays. Only a very low number of road users (less than 10 percent of daily traffic) travel on this stretch during the period when the road was closed (from 8 p.m. to 6 a.m.).
Why did the tunnels on the A8 undergo expansion?
The tunnels were not actually undergoing expansion. They were in fact being upgraded to bring them into line with the latest safety standards. Switzerland’s safety requirements were made more stringent following a series of major fires in motorway tunnels (Gotthard, Tauern, Mont Blanc).
Why does maintenance work take so long?
The work to be carried out on the A8 did not involve basic maintenance tasks, but rather the total renovation of the road infrastructure. Some components were displaying clear signs of damage and needed to be adapted so that they comply with the latest technical and safety standards. The stretch between Interlaken-Ost and Brienz passes through fairly steep terrain. Therefore, numerous engineering structures (bridges, retaining walls, support structures, etc.) needed to be renovated. In addition, the renovation of the tunnel infrastructure was also a complex and time-consuming task. This applied especially to the ventilation system in the Giessbach tunnel.
Is motorway maintenance in Switzerland carried out as a result of a desire for perfection?
Motorway maintenance is not a luxury, it is an essential road safety factor. The requirements placed on the quality of road surfaces and on the infrastructure are very high in Switzerland, especially in view of the major temperature fluctuations they have to withstand here. Road surfaces can heat up to around 70° C in mid-summer and are exposed to temperatures of around -20° C during the winter. These fluctuations mean that the right type of construction material has to be used, which must be neither too hard nor too soft. Surveys have shown that the majority of the population regard both the structural and the operational maintenance of the motorway network to be appropriate.
How can I keep myself informed?
- By regularly visiting this website.
- By consulting the “info” newsletter that is delivered regularly to all households in the Interlaken/Oberhasli region and can be downloaded here (only in German).
- By downloading the “SRF Verkehr” or another traffic information app to your smartphone.
- By listening to traffic bulletins on Radio SRF or private radio stations.
- By contacting us