The scenic county road 63 at Trollstigen runs through steep slopes and is a popular tourist destination in Western Norway. The most spectacular stretch of road 63 consists of 11 turns climbing from Isterdalen to Stigrøra. The bedrock outcrops at the steepest parts of the slopes and consists of fractured gneiss, and amphibolite. Below the steep sections the bedrock is covered by colluvium and till deposits.

Snow avalanches, ice falls, rockfalls and debris flows frequently affect the road which is closed during winter but has a very high traffic density in summer. Due to the very high exposure to natural hazards in Trollstigen Norwegian authorities have categorized the road as Highly prioritized.

Within the Klima2050 project, a weather station and a local weather radar was installed at Trollstigen. In addition, the slopes were characterised during field surveys using photogrammetry and lidar techniques. To generate synergies with the Klima2050 project, Trollstigen has been selected as an additional case site for the NordicLink project.

Case site objectives:

  1. Analyse the relationship between hydrometeorological variables and rockfall and debris flow initiation.
  2. Asses the change in the frequency of natural hazards in the area with climate.
  3. Develop tools that can be implemented into an Early Warning System for Rockfalls and Debris Flows to limit road closure times and reduce the exposure of population.