Operational integration of uncrewed aerial vehicles into roadway agencies' snow avalanche risk assessment process

In Norway, as in other mountainous countries, snow avalanches pose a serious threat both to the users of their transport network and that system’s infrastructure. Road closures caused by avalanche danger or occurrence result in high economic costs and impact the reliability of Norway’s critical transport network. The Norwegian Public Roads Administration (NPRA) is responsible for maintaining important routes that are threatened by snow avalanches. Keeping these roads open requires expensive operations to assess and mitigate avalanche risk. The GEOSFAIR (Geohazard Survey from Air) project has explored the use of Uncrewed Aerial Vehicles (UAVs) for snow avalanche assessment to support the NPRA’s programs to keep critical mountain roadways open and safe. A three-year effort, GEOSFAIR was led by the NPRA in collaboration with the Norwegian Geotechnical Institute (NGI) and SINTEF research institutes. This effort focused on developing effective methodologies for integrating UAV technology and UAV-collected data into the present NPRA decision support system for avalanche risk assessment. The project has provided new and valuable information for decision-making and has developed guidance for roadway agency staff to assess avalanche risk using UAV data, including determining the effective use of UAV-carried sensors and cameras. A on-line table was created to relate snow, avalanche and terrain properties, important to the NPRA’s avalanche forecasting staff,
to the capabilities and feasibility of UAV data collection. A detailed workflow for UAV operations by NPRA staff was developed by the project team. The team also demonstrated that effective avalanche data collection required operation in difficult weather and complex terrain, such that an occasional loss of aircraft and equipment damage will occur and should be accepted by roadway agencies operating avalanche programs