Avalanche warning in Fortunsdalen during the construction of the Illvatn pumped storage hydropower plant

Protection of the access road

Facts

Project: Site-specific avalanche warning in Fortunsdalen during the construction of the Illvatn pumped storage hydropower plant
Place: Fortunsdalen in Luster municipality, Sogn
Country: Norway
Year: 2025-2030
Customer: Hydro Aluminium AS Hydro Energi Sogn
Protected Objects: Construction access road
Installed systems: WAC.3® IDA® Infrasound detection system, Weather station, PTZ camera
Provided services: Site-specific avalanche warning

Initial Situation

Beginning in winter 2025-2026, Hydro Energi AS will use the avalanche-prone construction access road between Øyane and Fivlemyr in Fortunsdalen in connection with the construction of the Illvatn pumped storage hydropower plant. Hydro writes the following about the project:

Construction will start in November 2025, with planned operation beginning in 2030. The power plant will pump water from Fivlemyrane to Illvatn to increase reservoir capacity and winter production, and also includes a new 13 kilometer-long power line.

The construction of Illvatn pumped storage hydropower plant will be Hydro‘s largest hydropower development in over 20 years. The accessibility of the construction access road during the winter is very important for flexibility, progress, preparedness, and costs. However, the construction access road between Øyane and Fivlemyr is located in a narrow valley close to the mountainside, which creates a complex avalanche risk situation. The road is approximately 16 km long, and approximately 6 km of this is considered to be at risk of avalanches. Avalanche release areas are located up to 1000 meters above the level of the road.

Our solution

Hydro has entered into an agreement with Wyssen Norge for avalanche services during the construction of the pumped storage hydropower plant. An important part of Wyssen Norge‘s delivery will be the preparation of an avalanche warning plan for Fortunsvegen and the implementation of site-specific avalanche warnings during winter operation of the road. This will allow the road to be used during construction even in winter, while ensuring the safety of contractors and other construction traffic.
To ensure a good data basis for avalanche warnings, we also supply several automatic weather stations, controllable (PTZ) cameras, and an avalanche detection system. Data from these systems is made available and visualized in the WAC.3® data platform.
Avalanche warnings for the winter of 2025/2026 were launched on November 27.

A Project of:

Wyssen Norge AS

Fosshaugane Campus, Trolladalen 30
6856 Sogndal
Norway
Tel.: +47 971 235 82
norway@wyssen.com
www.wyssenavalanche.com
Paul Velsand
Tel. +47 454 611 78
velsand@wyssen.com
paul_velsand