Alaska DOT&PF Awarded $1.13M for Avalanche Mitigation Technology along the Seward Highway Corridor
By David Nyman
TNews Contributor
With the weather visiting southcentral this week, new funding to support southcentral avalanche mitigation efforts is timely. Alaskans traveling the Seward Highway between Anchorage and Seward will get a safer highway with the Avalanche Mitigation Alert Detection (AMAD) project that was recently awarded $1.13 million award as part of a Strengthening Mobility and Revolutionizing Transportation (SMART) grant program. This grant program is a component of the bi-partisan infrastructure law and from US Department of Transportation.
The AMAD project being led by the Alaska Department of Transportation & Public Facilities (AK DOT&PF) will utilize cutting-edge remote avalanche control systems and forecasting technology to mitigate significant avalanche risks along the Seward Highway corridor. The Seward Highway is a National Highway System (NHS) route and one of Alaska's busiest roadways, serving as a vital connection between the Kenai Peninsula, Seward and Anchorage, for commerce, residents, and visitors alike.
The grant funds will be used to support at least three different technologies to mitigate avalanche risk. This includes installation and monitoring of infrasound sensors. Infrasound is low-frequency sound that are inaudible to humans but travel long distances efficiently and can be recorded using specialized microphones. The infrasound processed data can provide detailed information on the nature of the slide activity. In addition, improved forecasting technology will provide state-of-the-art data analysis to support proactive decision-making and enhance traveler safety. AK DOT&PF plans to install the infrasound system between MP 97 and 99 along Bird Flats.
Wyssen Avalanche Tower with hanging charge (Photo courtesy of Wyssen Avalanche Control)
Alaska DOT&PF also hopes to also deploy Remote Avalanche Control Systems (RACS) for avalanche mitigation. One type of RACS consists of a hanging charge avalanche tower that leans out over the avalanche starting zone. The tower is preloaded with explosive charges that can be remotely activated and lowered on a tag line to just above a snowpack followed by remote detonation. Most of the RAC system technology originates and is manufactured outside of the United States. Due to the grant federal funding source and provisions of the Build America Buy America Act, AK DOT&PF must apply for waivers to allow funds to be expended on non-US manufactured technology. RAC systems are planned for installation along Bird Ridge between Bird Creek and Girdwood.
A third technology is the use of Doppler radar to detect slide activity. “A radar system is good for detection and potentially once it is proven out it can also close the road with automated gates or activate flashing lights. With radar detection system that is proven out you can almost eliminate the risk and preventively close the road so that vehicles don’t drive into the avalanche zone,“ said Tim Glassett, AK DOT&PF Statewide Avalanche and Artillery Program Manager.
Timothy Glassett points out that a similar radar system is currently employed to monitor the “slow moving landslide” on Barry Arm in Prince William Sound. While the Barry Arm landslide currently shows no signs of large-scale active deformation smaller-scale instabilities on the surface of the landslide still pose a threat of localized tsunami generation in Barry Arm.
“This grant allows us to leverage advanced technology to address one of the most pressing safety issues we face on Alaska’s highways,” said AK DOT&PF Commissioner Ryan Anderson. “By deploying these systems in along avalanche prone areas above the highway, we’re improving safety and reliability for all who depend on the Seward Highway, while demonstrating Alaska’s leadership in transportation innovation.”
Avalanches pose a serious threat to both motorists and the maintenance crews who work to keep the Seward Highway open. The AMAD project’s advanced technology will enhance the department’s ability to predict and manage avalanches, and significantly reduces the risks to the DOT&PF maintenance team and the traveling public.
The link below provides additional information of AK DOT&PF avalanche risk reduction initiatives: