Associate professors H.P. Marshall and Jeff Johnson in the Department of Geosciences, along with Sin Ming Loo, a professor in the Department of Electrical and Computer Engineering, recently installed several low-frequency microphones for avalanche detection in Little Cottonwood Canyon, Utah.
Their research project is funded by a consortium of Department of Transportation (DOT) avalanche forecasting offices across the Western U.S., and is focused on development and testing of real-time avalanche detection for the mountain highway outside Salt Lake City, which provides access to the popular ski resorts of Alta and Snowbird. The DOT currently employs two avalanche detection systems, however, these systems are nearly 10 years old and their technology is no longer being supported or sold by the company that built them. The DOT is looking for ways to upgrade and expand their avalanche monitoring capabilities. During ski season more than 10,000 vehicles per day navigate this corridor, which must often be closed in response to avalanche hazards.
“The goal is a system that will detect avalanches in real-time and alert the avalanche forecasters,” Marshall said. “At this stage we are deploying three different systems to determine which approach is the best for an economical system that the DOT avalanche offices can afford, so we will travel monthly to the site to retrieve the data. The step after this winter will be to add the real-time communication.”
Some of the microphones have been installed in the air above the eventual snowpack, and some have been installed near the ground, below the eventual snowpack.
Between 2012-15, Marshall, Johnson and recent Boise State geosciences doctoral graduate Scott Havens deployed avalanche detection systems along Idaho’s “Avalanche Alley,” the section of Highway 21 between Lowman and Stanley. Because of this work, the team was able to track and measure the speed of a large avalanche that hit the highway – work that resulted in a publication led by Havens in Geophysical Research Letters.
But during large avalanche cycles, Highway 21 is closed, which prevents researchers from making independent observations of avalanche activity. In comparison, Little Cottonwood Canyon is one of the most well instrumented, monitored and avalanche-prone highways in the U.S., making it a perfect test bed for the three new avalanche detection systems the team will be testing this winter.
All three systems use the same approach – measuring sound at low frequencies. However, one system is the standard infrasound system used by Johnson in volcano research; one system was developed by Loo’s student research group to detect gun shots; and the third system is a low-cost approach designed by one of Johnson’s doctoral students, Jake Anderson.
The team will visit the site monthly throughout the winter season to check on instrumentation, dump data and observe avalanche cycles during avalanche control missions with forecasters. This project will allow the team to recommend the most cost-effective approach to avalanche detection for highway operations in the U.S.