Large Avalanches on Skyline Drive
The recent heavy snows along the Skyline Drive and the activity of snowmobilers in the area led to a series of avalanches in this area. Snowmobiles were buried, but the riders were not injured in the snow slides.
mobiles were buried, but the riders were not injured in the snow slides. Eric Trenbeath is the avalanche specialist for the Manti-LaSal National Forest, "The snowmobilers that triggered the avalanche on March 8 were very lucky they were not buried. It did bury a machine. The Huntington and Fairview Canyon are very prone to avalanche. There are a lot of 35 degree slopes up there. Generally slopes between 30 and 40 degrees are avalanche prone. Huntington/Fairview is used by a large group of snowmobilers. Forty-four percent of avalanches triggered by humans are by snowmobiles. The machines are more high-powered these days and can climb up the steeper slopes. There has been a dramatic increase in snowmobile triggered slides in recent years. There are a number of incidents in the Huntington/Fairview area; five years ago two snowboarders were killed in an avalanche. Last winter in the Seely Canyon area a guy was buried and his machine created an air pocket around him until they were able to dig him out. Avalanches are becoming a regular occurrence and more and more people have been going for rides along the path of these avalanches, which are usually triggered by them or one of their buddies.
"The key to staying safe is avalanche awareness and education. We encourage people to check our website for an avalanche advisory at www.avalanche.org. This gives regional information an information on avalanches throughout North America. The site gives weather information and snow conditions and avalanche danger. We teach classes to snowmobilers, land management agencies and other users. At one of our training classes it was two days after a big storm and the avalanche danger was high in the canyon that day. It was a sunny day and within two hours time there were a reported six avalanches and two burials. You always need an avalanche beacon and carry a shovel on your machine. When you are buried in an avalanche the snow sets up around you like wet cement and there's no way you can dig yourself out. One guy was found with his hands sticking out of the snow and he died of suffocation that close to the top. If you're buried then your buddy better locate you and dig you out within 15 minutes or you will die of suffocation. After 15 minutes the chance of finding someone alive diminishes greatly.
"There is an international avalanche danger rating which are: low, natural avalanches are very unlikely, human triggered avalanches are unlikely. Travel is generally safe in all terrain for travelers of all skill levels. Normal caution is advised to enforce good habits while traveling in slide paths...one at a time, never cross above your buddies, have an escape plan in case you are caught by a slide and get out of the way at the bottom. Moderate: natural avalanches are unlikely, human-triggered avalanches are possible. Use caution in steeper terrain, especially on aspects identified in the avalanche advisory. Considerable: natural avalanches are possible, human-triggered avalanches are probable. Be increasingly cautious in steeper terrain. As always, be prepared to change your plan or back off if things don't look right...even if it was a long hike. High: natural and human-triggered avalanches are likely. Travel in avalanche terrain is not recommended. Use all of your sneaky tricks for staying out of trouble...stay out of run-out zones, stick to dense trees, low angle slopes and ridgelines away from cornices (overhanging snow). Extreme: widespread natural or human-triggered avalanches are certain. What are you doing in the mountains, anyway? It's probably dumping snow and blowing hard. Stay well away from avalanche path run-outs and travel only in low angle terrain.
"A snowboarder awhile back was killed when the overhang (cornice) he was standing on gave way and carried him to the bottom of the ravine where he was buried. You've got to know if the snow you are on is stable. If you hear noise and settling you better get out of there. Natural occurring avalanches come and release by themselves all of the time. Ninety percent of victims killed are done so in a slide that they triggered themselves. They will see a natural slide that has occurred and climb up the slope right next to it and you can't do that. You've got to be aware of where you are and your surroundings at all times. This season alone in North American there have been 40 avalanche deaths.
"This past week there was approximately six inches of new snow in the canyon. We have our field staff up there checking and collecting data to update the advisory every week. There are so many users in that canyon...the vehicles line up along the sides of the roads and there are hundreds of people up there each weekend. We want them to be able to play in the snow, but to do it safely and responsibly. We've had a pretty big season with numerous natural slides. We had a lot of snow over the holidays and then a big dry spell in January and February. The snow deteriorates and is weak and then when you get fresh snowfall the underlying snow can't hold it and it slides. In the public domain we don't do any control work on avalanches. All we can do is advise people of the dangers.
"Another thing is important for people to realize is that it doesn't take a big slide to bury and kill you. A small slope of snow on a hill 50 feet tall can slide and bury you and it doesn't take that much. A slide 75 feet wide with snow one-two feet deep can take you for a ride and bury you. Most are not huge catastrophic events. The snowpack tells a history of the winter, like how warm its been and if there have been a lot of thaws which tend to deteriorate the snow stability. Then you get some heavy wet snow on top of this and it leads to the unstable snowpack. You never know how much weight this unstable snowpack can hold. You need to know what the signs of instability are so it's good if you're out in the back country a lot to take one of our training classes. You've got to know that the first sign is natural occurrences of slides in the area, if you see a natural slide do not climb up the slope next to it.
"We will be finished with our advisories for this year around the middle of April. This is the fourth year we have been doing the avalanche advisory. The snowmobile hotline number is 1-800-648-7433 and snowmobilers can call that number for current avalanche conditions or check our website," said Trenbeath.