Monitoring and modelling snow avalanches to innovate road safety management in alpine valleys

Snow avalanches threaten people and infrastructure in alpine regions. Each winter situations occur that require road closures, which have a major impact on the affected people and economy. The decisions on road safety measures are done by local experts, who decide based on information from the avalanche bulletin, weather forecast and most importantly personal experience. Valuable, detailed information about the snow depth distribution, especially in avalanche release areas is not available in sufficient resolution. To fill this data-gap, we propose a remote-sensing based approach to map, monitor and model the snow depth distribution and its development in avalanche release areas, with high spatial and temporal resolution. The main applied technologies are photogrammetry and LiDAR, both air-borne and ground-based. The newly build up snow database will serve as input to improve the simulation of avalanches and especially the runout distance, which is ultimately crucial for the decision of closing or re-opening a road.