Avalanches are some of Mother Nature’s most impressive handiwork. Tons of loose snow or huge snow slabs can come crashing down a mountain, closing roads, trapping backcountry skiers and destroying everything standing in the way. Setting off a slide before it happens helps keep people safe and highways open.
The intentional triggering of avalanches is called avalanche control, but, according to Ray Mumford, CDOT transportation maintenance supervisor and avalanche control coordinator, that term is misleading. “When dealing with Mother Nature, there is no such thing as control. We just try to minimize the risk of an avalanche coming down.”
Mumford has worked with CDOT for more than 32 years and has been involved with avalanche control for most of that time. His group is responsible for the area that includes Loveland Pass, Berthoud Pass and the Eisenhower tunnel approaches. It also helps with avalanche work on Independence Pass before the pass is opened in spring.
Is avalanche control something you always wanted to do?
It definitely gets in your blood. You have to love what you’re doing or you shouldn’t be doing it. It requires a heavy time commitment beyond the job. There’s a lot of training with the devices for control work, certifications, background checks and the required licenses and permits.
What’s the biggest challenge of your job?
Dealing with Mother Nature. She has a lot of secrets she doesn’t reveal and she controls everything we do. A change in the weather pattern, like a wind shift through the night, always gives us trouble. Wind is one factor we watch closely along with snow and the amount of snow. Windblown snow has two times the weight of regular snow.
Another challenge … is closing the highway. We have to do control work first thing in the morning before the whole area becomes full of backcountry users, and that causes problems with traffic. We understand the frustration of drivers trying to get to the ski slopes, but there are things we have to get done. We try to get out of the way as quickly as we can. The driving force is safety on the highway.
What processes are involved in avalanche control?
We work with the Colorado Avalanche Information Center forecasters and they let us know when we need to do control work. They keep track of the snowpack, especially the weak layers in the snowpack. The forecasters know where we should place our shots into the avalanche start zone.
What equipment do you use during control work?
There are about 15 people who are trained to use the different control devices. We use military artillery guns like the 105mm howitzer, smaller avalancher guns and helicopters to place larger charges at the top of the mountain. Sometimes we’ll snowshoe to the top of an avalanche path and throw charges by hand.
What are some recent examples of control work?
On Dec. 21, we fired rounds with the howitzer and released a good-sized avalanche in the Stanley avalanche area on Berthoud Pass. The fracture was 1,000 feet across and slid 2,200 vertical feet. On Jan. 3 we put several large charges from the helicopter into the Stanley with no results. Then on Jan. 6, the day of the Berthoud Pass avalanche (which carried two vehicles with it), we fired six rounds with the howitzer into the remaining snow that didn’t slide in the initial avalanche before the cleanup crews began clearing the debris.
What procedure do you go through before setting off a charge?
From the helicopter, we place a charge, and there’s a preset time for it to go off. With the military weapons and guns there’s a sequence of commands that follow military guidelines before firing. Then there’s a loud ringing noise right after that.
