Avalanche hazard reduction for transportation corridors using real-time detection and alarms

Increased travel demand for safe, reliable winter travel on the alpine roads of the Western USA has resulted in an increased hazard to motorists and highway maintenance personnel from snow avalanches. Presented here are configurations for systems that can detect and provide, in real time, warnings to motorists and highway maintainers of the onset of avalanching onto the roadway. These warnings include: on-site traffic control signing and in-vehicle audio alarms for winter maintenance vehicles, as well as notification capability to maintenance facilities and/or centralized agency dispatchers. These avalanche detection and warning systems are capable of detecting an avalanche-in-progress and use the remaining Time of Descent of the avalanche to initiate the on-site alarms. Alternatively, real-time knowledge and notification of the onset of avalanching may be used to proactively manage the evolving hazard over an affected length or corridor of highway. These corridors can be several tens of kilometers in length and may, otherwise, be very remote, low volume rural highways. As a consequence, these systems must be cost-effective alternatives to presently available avalanche hazard reduction technology used on highways. Results and experiences from deployed systems in Idaho and Wyoming from the winters of 1997/98, 1998/99, and 1999/2000 are presented here.