Avalanche warning during reconstruction work on power lines in Skjomen
Facts
| Project: | Damage to 420 kV pylon in Skjomen in spring 2025 |
|---|---|
| Place: | Skjomen |
| Country: | Norway |
| Year: | 2025 |
| Customer: | Sweco Norge / Statnett |
| Protected Objects: | Power line |
| Installed systems: | WAC.3® Cockpit and Avalanche warning systems |
| Provided services: | Avalanche warning planLocation-specific avalanche warningField observations |
Initial Situation
On Tuesday, March 18, two 420 kV power lines in Skjomenfjella in Nordland failed due to two separate avalanches. The outages were among the largest Statnett has ever experienced. The power supply between southern and northern Norway was interrupted for 57 days. In Skamdalen, a 39-meter-high pylon was damaged, tearing down a conductor cable. At Vadbakkvatnet, the avalanche shifted another pylon 90 meters downhill, tearing down all the conductor cables and also damaging the neighboring pylon.
Rapid repair of the lines was crucial, but the repair work proved extremely challenging due to the difficult terrain, adverse weather conditions, and the continuing avalanche risk.
Our solution
To ensure both safety and progress, Wyssen Norge and Sweco provided daily avalanche warnings from March 26 until the power lines were back in operation on May 14. As this was an emergency operation in a remote region, the avalanche experts initially had only limited knowledge of the local conditions, weather conditions, and the client‘s organization. The operation was therefore reinforced with an avalanche expert from Wyssen on site, who was present at all times throughout the entire duration. The avalanche expert was on duty during the day, observing the weather and snow cover along the transport routes and construction sites, and issued an avalanche warning before work began the next day. The weather in March and April 2025 was changeable, which highlighted the importance of the continuous presence of avalanche experts on site for the progress of the work, the safety, and the sense of security of the employees on the construction site. The avalanche expert‘s knowledge of weather and snow conditions also proved valuable for the short-term and flexible prioritization of resources. Continuous on-site monitoring and daily avalanche warnings accompanied the reconstruction of the pylons until power was restored on May 14.
A Project of:
Wyssen Norge AS
