Tuesday, Jan. 11, 2005 | 11:05 a.m.
The huge avalanche that fatally swept a 13-year-old Las Vegas boy off a ski-resort chairlift above an open run was not your typical avalanche, experts said.
It was unusual first and foremost because of where it struck. Less than one-tenth of one percent of avalanche fatalities -- one in 1,000 -- occurs on an open ski run or a highway.
In general, avalanches generally do not strike without warning and are relatively controllable within confined areas, according to Drew Hardesty, an avalanche forecaster with the U.S. Forest Service's Utah Avalanche Center.
"Ski areas are knocking avalanches down, so there's not as much danger," he said.
The lethal slide was also extraordinarily large -- it is thought to have been at least 10 feet deep.
On the five-point scale by which avalanches are measured, where 2 would bury a person and 5 "would destroy a Swiss village," an avalanche more than eight feet deep would likely be at least a 4.5, Hardesty said. The average avalanche is one- to two-feet deep.
"This is certainly a classic case of unusual weather conditions producing unusual avalanches," Hardesty said. "It's very unusual to see them this deep."
Mount Charleston was still under avalanche advisory Monday night, with Metro Police advising residents to leave the area.
Experienced back-country recreationists -- those who ski, snowboard, snowmobile, snowshoe or climb outside ski-area boundaries -- customarily take avalanche precautions. But those at ski areas usually assume they are safe, and for the most part they're right, said Ed Adams, an avalanche expert at Montana State University.
"In a ski area, where avalanches are constantly being controlled, or along highways, you can do a good job of monitoring and controlling them," Adams said.
"Generally, they (ski resorts) try to place lifts so they aren't exposed (to avalanches)," Adams said. "If that's not possible, they generally try to put up some sort of protection."
At this point, officials said they do not believe any negligence on the part of the Las Vegas Ski and Snowboard Resort caused the death of Allen Hutchison, a snowboarder who was an eighth grader at Sig Rogich Middle School in Summerlin.
Although the boy suffered blunt-force injuries, the cause of death was suffocation, the Clark County Coroner's Office said.
Avalanche victims who aren't killed on impact generally die because exhaled carbon dioxide builds up around them and poisons them, not because they run out of oxygen to breathe. After two hours, 80 percent of those buried in the snow die.
Thus far, officials do not believe the avalanche could have been foreseen and the death prevented.
"This was something completely unexpected, not something they would have been able to prevent," said Robbie McAboy, the Forest Service's recreational staff officer for the Spring Mountain area.
"The chute this avalanche came from was not one that looked like an avalanche would come from it," she said.
A team of Forest Service experts from across the West, in conjunction with resort personnel, is to begin investigating the incident today, McAboy said.
The investigators will take a thorough look at what caused the avalanche, how rescuers responded to it and whether the area as a whole is totally safe, she said. But based on regular inspections, the resort is believed to have been in compliance with the permit that allowed it to operate a ski facility on National Forest land, McAboy said.
The investigators hope to be finished in as little as two days and the area could reopen as soon as Wednesday, McAboy said. But if any areas are found to be dangerous, the resort will remain closed until it can be made safe, she said.
The resort's general manager, Brian Strait, said while the company is extremely saddened by the boy's death, he stood behind the decision allowing the resort to open and stay open on Sunday.
"Based on our hazard analysis, we determined it was safe to open," he said. The danger was monitored throughout the day as well, he said.
"When you're dealing with the forces of Mother Nature -- and we're dealing with an avalanche of unprecedented magnitude -- there was no way for any of us to predict that that was going to occur at 3:30 (Sunday) afternoon," Strait said.
The boy was the 12th person to be killed by an avalanche in North America this winter and the first in Nevada. No one has ever died in an avalanche at the Las Vegas Ski and Snowboard Resort since it opened 40 years ago, officials said.
The last avalanche death in Nevada was in the Reno-Lake Tahoe area in 2003, according to the Colorado Avalanche Information Center.
Young Allen was not the first to be claimed by the extraordinary storm system currently sweeping the Southwest. In two separate avalanches in Utah on Saturday, a snowboarder and a snowmobiler were killed.
In southern California over the weekend, at least nine people were killed by flooding and landslides, the Associated Press reported.
Avalanches happen because snow piles up in layers, like a layer cake tilted at a steep angle. Given a little nudge or a little pressure, the top layer may slide off if the icing between the layers isn't strong enough.
Almost all avalanches happen at a slope of 35 to 45 degrees. Many are triggered by wind that picks up snow on one side of the mountain and deposits it on the other.
But the image of snow crashing down from above on someone who just happens to be in its path is a myth, experts say. Among lethal avalanches, 90 percent are caused by the victim or someone accompanying the victim. The person's weight, though tiny in comparison to the mass of snow, becomes the straw that breaks the camel's back.
In confined spaces such as ski areas or the sides of highways, avalanches can be controlled for the most part by monitoring terrain, weather conditions and snowpack, then detonating explosives in potentially unstable areas to defuse potential avalanches, said Rod Newcomb, director of the American Avalanche Institute in Jackson, Wyo.
"(Avalanche) forecasting is an art in the backcountry, but in a ski area it's more of a science," Newcomb said. That's because more data is available and the boundaries, and most routes down the mountain, are defined, he said.
Strait said his resort did everything that could be done.
"Avalanche control measures and snowpack analysis were conducted Sunday morning in known avalanche paths," Strait said. The area under the chairlift was known to have potential for avalanches, but previously only small, nondangerous ones, he said.
On Sunday morning, eight rounds were fired from an avalanche control gun and four hand rounds of explosives were discharged, according to a statement from the company.
But nothing moved, the company said.
That's a tricky situation, Newcomb said. In most cases, it means that the snow is so stable that nothing will dislodge it. But it could mean that the snow, destabilized from the explosive blasts, is just waiting for the weight of a skier, or the next gust of snowy wind, to set it off.
"Thowing the explosive may weaken it to the point that the third or fourth skier could trigger it, but it's more likely that that means it's stable enough -- unless it's still being loaded with new snow," Newcomb said.
In the backcountry, electromagnetic beacons and other equipment can reduce the risk, Newcomb said. But most patrons of ski resorts aren't thinking that way.
"The ski area mentality is, when you buy a ticket you assume the slopes are safe," he said. "Then it depends on the ski patrol's training and how quickly they can get there and set up a probe line."
The probe line consists of patrollers who push poles into the snow and sweep from side to side, then advance in a line. According to the company, an 18-person probe line was in place on top of the mountain "within minutes of the slide."
Three Metro search and rescue dogs arrived about two hours later and eventually helped find the boy after almost seven hours. The resort does not have any dogs on staff, Strait said.
Dogs don't do much good when someone is completely buried as they can only pick up smells that make it to the surface, Newcomb said.
The probers try to cover as much ground as quickly as they can, knowing that time is short. "Statistically, a person completely buried has a 50 percent chance of living past the first 25 minutes," Newcomb noted.
The resort is owned by Powdr Corp., which owns five other resorts -- including Utah's Park City Mountain Resort -- in Utah, California and Oregon.
Powdr bought the Las Vegas Ski and Snowboard Resort in November 2003 and has plans to expand it. Currently, the small area has three lifts and 11 runs.
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