Utah’s Wasatch Mountain Range receives large amounts of snow, and with that comes serious avalanche problems to mitigate. Whether by ski resorts or the Utah Department of Transportation, great efforts are made each season to keep the public safe from avalanches. Little Cottonwood Canyon (LCC) provides incredible access to world-class skiing, only miles from metropolitan Salt Lake City. More than half of the entire stretch of LCC cuts directly through active avalanche paths, causing significant concern for commuters who use this road daily.
Early Avalanche Mitigation in Utah
Utah in particular has long been at the forefront of avalanche control work, dating back to shortly after Alta Ski Area was opened to the public. In 1939, the USFS hired a fellow called Douglas Wadsworth to be the first Forest Service Snow Ranger, according to the Central Wasatch Commission. Wadsworth formulated the first set of rules to increase safety from avalanches in LCC and across the nation on forest service land. In 1946, the USFS appointed Monty Atwater, a discharged 10th Mountain Division soldier, to be the first Alta Snow Ranger in the LCC area, according to the CWC. Atwater was the first to consider using a 75mm howitzer artillery cannon to intentionally trigger avalanches preemptively, to increase safety in the area.
U.S. Army National Gaurd Involvement
In the beginning, military artillery was only authorized to be used by Army National Guard personnel. This restriction was later modified to include authorization for USFS Snow Rangers to fire the artillery, conserving Army resources. The U.S. Army has always been the sole supplier of the machines, as well as the ammunition for use in them, being a coveted resource that must never fall into the wrong hands. For a considerable time, the U.S. Army has been pushing to transition avalanche mitigation techniques in a new direction and away from military-supplied artillery. This push is what has brought about innovations in the ways that we deal with avalanche risks in the modern era.
Alternate Avalanche Mitigation Tactics
Ski Patrol personnel regularly set out on skis to access remote locations that cannot be accessed by howitzer artillery. These trained professionals use techniques such as ski-cutting slopes to initiate avalanches below them and remain above the slab that fractures. Hand-throwing explosive charges is another technique used by patrollers in remote areas of known avalanche activity. While these methods are effective, they do come with a fair amount of danger for the personnel involved and can be labor-intensive. These tactics are time-consuming and involve large coordinated efforts by many personnel to operate effectively and safely.
The Future of Avalanche Mitigation
Remote Avalanche Control Systems (RACS) are the future of avalanche mitigation work, becoming more prevalent and innovative in modern times. These remotely detonated systems are implemented from stationary locations and are installed in the summertime for use through the winter season. These systems save control workers both time and effort in reaching remote locations to perform control work. Most importantly, personnel are kept out of the mitigation zone entirely, significantly increasing safety and efficiency simultaneously. Additionally, this increase in personnel efficiency allows patrollers to open terrain faster on deep powder days while utilizing fewer resources.
Wyssen Towers
Wyssen Avalanche Towers, manufactured in Switzerland, are a new concept in remote avalanche mitigation. The LS12-5 tower can hold up to 12 charges per deployment box, while the LS24-5 tower can hold up to 24 charges per deployment box. Charges are deployed remotely using a laptop or even a smartphone from a secure location away from danger. Once deployed, the explosive charge hangs from a cord seven to ten feet above the snow surface until remotely detonated. One unique benefit is the versatility of using standard explosive charges or a Wyssen-specific charge that remains inert until just before detonation. This option increases the safety of personnel during the process of restocking explosive charges in the deployment boxes. Loading charges on Wyssen towers is performed by helicopter but can be carried out by a solo pilot without assistance.
Gazex/Gazflex
These are a tried and true platform for remote avalanche control work, manufactured by MND Safety out of France. This specific system has been in use for 30 years in 20 countries across the globe, with great effectiveness. These detonation tubes create a directed explosion toward the snow surface, igniting a specific mixture of propane and oxygen. Three different models are offered, each one is fully remote and can be detonated in any weather conditions. Power is supplied through solar panels and remote detonation keeps control workers in a safe location throughout the mitigation process. The restocking of gas supplies must be done by helicopter due to the remote locations of these systems.
O’BELLX
Another product offered by MND Safety, this system has a few differences compared to Gazex systems. The O’BELLX has a removable cone perched atop a support tower that contains the gas mixture used in detonation. This system is also reliant on a helicopter to replenish the gas supply but can be attached and removed without any human assistance on the ground level. In similarity with Gazex systems, is the method of directing a controlled blast toward the snow surface to initiate avalanches. Two different capacities are available, with the O’BELLX Option+ doubling the supply to 30 blasts compared to the standard option. This system is utilized fully remotely and can be detonated simultaneously or synchronized with additional towers to increase effectiveness.
BoomWhoosh
The newest remote avalanche control platform, the “BoomWhoosh,” has a few differences that set it apart from others. Manufactured by Zmont and Alpine Infrastructure, based out of Jackson, Wyoming, this is the first remote avalanche system built in America. One significant benefit of this system is that it is not reliant on a helicopter to supply gas or perform maintenance. The BoomWhoosh is supplied through a gas line, with a reserve tank far away making refills much more accessible and eliminating the reliance on helicopters. This is a game changer for RACS technology as helicopter support can be incredibly costly and cannot be performed in inclement weather. Zmont and Alpine Infrastructure are in the process of designing the first adjustable RACS tower to better serve locations with a varying snowpack from year to year.
As avalanche mitigation experts get away from using military artillery, avalanche-prone areas will begin to see more use of RACS. These systems greatly increase efficiency, while significantly reducing the effort put forth to achieve the same result. More importantly, safety is drastically increased by keeping personnel out of harm’s way and in a safe location during the mitigation process. And while helicopter assistance with RACS is expensive to execute, it’s hard to put a price tag on the increased safety of avalanche control personnel.
