The explosive business of avalanche control keeps the ski area slopes safe for guests.
On many winter days explosions can be heard echoing across many ski areas. These are the sounds of avalanche mitigation.
Dutch Draw Avalanche
Last week an avalanche was reported in the Dutch Draw area of Park City, Utah between the lifts Peak Five and Ninety-Nine 90. According to Andy Van Houten, snow safety director of Park City Mountain, the avalanche occurred in the back country. “We worked with the Department of Public Safety helicopter,” he said. “It was established that nobody was involved. We had all of our witnesses accounted for, all is good.”
“There is no mitigation outside of the resort and so it’s 100% on the on the user, on themselves; we do worry about it from a rescue perspective but we do not do anything to mitigate that hazard,” Van Houten said.
There are a few ways the ski patrol can mitigate avalanche risks. While the explosive business is the most dramatic two other methods are used as well. Ski cutting and compaction.
Ski cutting is where a patroller will ski intentionally across the top of a slope. This may trigger an avalanche as the slope is traversed. This method is used on smaller slides.
Another form of mitigation is called skier compaction.
“The best thing we can do is get this terrain open to public and get it skied,” Van Houten said. “That’s why we push so hard to get this terrain open, you know, in a timely fashion is that so we can get our guests up there to ski it and that’s what helps us, that kind of skis all the snow and it breaks up the layers that build up.”
For bigger slopes there is the explosive business. There is a typically team of patrollers who go out in groups of two or three and carry explosives in their backpacks.
“It’s a cast booster, it’s about the size of a large can of soup and it’s a pentolite TNT combination,” Van Houten said. “It’s got 120-second fuse strain on it. It’s basically like a little cardboard tube and that’s it’s got a sparker in it. When we pull that, that’s what ignites the end of the fuse train. We either rope them, or we just throw them. And it’s like throwing a can of soup into the snowpack. It’s a good-sized shot. But we are usually pretty far away when it detonates and we kind of plug our ears and kind of turn our backs to it a little bit. So we’re not we’re not close to it by any means.”