Insights from Snow Avalanche Detection in Norway: A Distributed Acoustic Sensing (DAS) Study

Snow avalanches pose a significant hazard in mountainous areas, especially when snowpacks block roads, either burying vehicles directly or exposing traffic to subsequent avalanches during active cycles.

We have been monitoring avalanche activity along road stretches in Northern Norway since 2022 using Distributed Acoustic Sensing (DAS),  a technology capable of theoretically covering spans of up to 170 km. Traditional detection methods often focus on only a limited section of a road stretch, making effective risk management challenging. DAS powered alert system can work unaffected by visual barriers and in adverse weather conditions. The developed algorithm identifies avalanches affecting the road and estimates accumulated snow. Moreover, the system can also detect vehicles on the road, offering invaluable support to search and rescue operations.

Over 3 winters the system successfully identified 10 road-impacting avalanches (100% detection rate). Our results via DAS align with the previous works and indicate that low frequency part of the signal (<20 Hz) is crucial for detection and size estimation of avalanche events. We have identified subsets of snow avalanches based on the paths they followed and discuss the snow accumulation and deposition signatures on signals. Various fiber installation methods are explored to optimize sensitivity in detecting avalanches. The findings highlight the system’s robustness and low maintenance demands, offering a clear advantage over conventional systems, which are costly to install, have restricted coverage, or are vulnerable to environmental factors such as weather and lighting.