By G.D. Maxwell
"It’s a simple equation. The more time you spend in the field, the greater your chances of being caught up in an avalanche."
The field the speaker was referring to was snowy mountains. The audience he was speaking to consisted of a handful of snow scientists, a couple of "guests" and a whole lot of people lucky enough to spend enough time in the field to call it their office – Canadian Mountain Holidays (CMH) heliskiing guides.
Chris Stetham, who was speaking, knows what he’s talking about. He’s spent a lot of time in the field himself. Most of it has been as a trainer, teaching people the art and science of deciphering snow packs. Of unlocking their secrets and making informed decisions – decisions with life and death hanging in the balance – based on what they reveal.
He’s spent a lot more field time researching snow that’s moved. Avalanches. Some have been benign, leaving only silence and a changed landscape in their wake. Some have been deadly, leaving torn bodies, shattered lives and unanswered questions. When he investigates a deadly avalanche, Chris tries to answer the ones he can, the How it Happened and Why it Happened questions. He prefers to leave the unanswerable ones, like Why Were They There, to others.
I have a feeling one of the questions Chris was trying to answer that day last December was what the heck I was doing in the audience. The answer, if not the circumstances, is the same one so many people who narrowly miss being swept up in an avalanche generally give: Just lucky, I guess.
Lucky enough to be invited to sit in on a week’s training and find out for myself what some of these people, who remember the horrific toll avalanches took last winter, think about heading back out into their field to spend endless days skiing untracked – and uncontrolled – powder in some of the most magnificent and rugged mountainscapes British Columbia has to offer. Lucky enough to get a glimpse of what it takes to keep the biggest heliskiing operation as safe as people can make it and still give their customers the thrill of a lifetime. Yeah, it’s a dirty job, but someone’s got to do it.
But what I was thinking about when Chris posited his simple equation was this: If he’s right, why aren’t these guys dead? What I learned about what they know shed some light on the answer to that question.
A Winter of Discontent
Last winter wasn’t the deadliest winter for avalanche deaths in B.C. history. In 1910, avalanches rolling down onto the Canadian Pacific line at Rogers Pass took the lives of 62 people. In 1965, 35 loggers and miners on the north coast were killed in two separate slides.
But the 24 people who were killed last season grabbed the attention of a country in ways avalanche deaths never have before.
On January 20 th , Ruedi Beglinger was lead guiding a group of 21 skiers and snowboarders touring on the Durrand Glacier in the Selkirk Mountains near Revelstoke. Ruedi, the owner of Selkirk Mountain Experience, was treating his guests to a fine morning of deep powder. Everything was textbook at 10:44. At 10:45, all hell broke loose.
A wall of snow some 30 metres wide and 100 metres long fractured and ran. The backcountry travelers were moving upslope in two groups. The 13 forming the lower group were buried. By the time they were located and dug out, seven were dead, including snowboarder Craig Kelly.
While the usual media frenzy with its inane questions about why anyone in his or her right mind would want to risk backcountry travel into avalanche terrain – mountains – followed, the controversy didn’t last long. The void between the public’s comprehension and the acceptance of avalanche risk by those who ski in the backcountry was underscored when a number of the same group were back on the slopes within two days, determined to finish their trip.
Since they were all adults and ostensibly appreciated the risks they were exposing themselves to, the furore over the unlucky skiers’ deaths would have followed its usual course – a coroner’s inquest, a report, deafening silence.
But last winter wasn’t a usual winter. During October, November and much of December, it seemed the season of 2002/03 was shaping up to be the season that never was. Unseasonably warm weather through November left rain falling at high elevations. On the 22 nd of November, a province-wide storm brought up to 5.5 millimetres of rain and left a nasty, icy layer on the sparse snow that remained and, in many place, on the ground and rock itself. Everything that accumulated after that – including a surface hoar layer at Christmas and another one January 20 th – was just a time bomb waiting for something or someone to light the fuse.
From the date of the Durrand slide to the first of February, 126 centimetres of snow fell on top of an already unconsolidated snow pack in the Rogers Pass area.
"We need your help, please."
The Connaught Creek drainage in Glacier National Park draws backcountry skiers on a winter weekend like watermelon draws flies on a warm summer’s day. Saturday, February 1 st , wasn’t much of an exception. Among the skiers who skinned up and headed into the valley – on a trail that can see upwards of 200 skiers on a busy weekend – were Rich Marshall and Abby Watkins, professional mountain guides from Golden on a busman’s holiday.
The avalanche information bulletin posted by Park staff advised travelers the avalanche danger rating was "moderate" below treeline and "considerable" at treeline and in the alpine. It also warned of the different weak layers in the snow pack and included this prescient language:
"Natural avalanche activity in the past 24 hours has been relatively small with a few size 2 avalanches noted from steeper terrain. The possibility of a human triggering avalanches at the surface hoar layer remains as does the potential for a triggered event to step down to one of the deeper instabilities."
Connaught Creek runs from west to east towards Rogers Pass. From the trailhead at the highway, it’s about 6 kilometres to Balu Pass. The valley drains high mountains on either side and while giving a sense of spaciousness, you don’t so much walk through it as you wear it. Looking up at the mountains on either side, what you see are numerous natural avalanche paths.
Around mid-morning, Rich and Abby passed a school group from Calgary. The 14 Grade-10 students, two teachers and a chaperon were sensibly paired up and spaced out 10 to 15 metres, a standard precaution for a large group traveling in avalanche country.
Not long after passing the students, Rich and Abby skied up into a stand of trees on the north side of the trail towards Hospital Gully and stopped for a snack and warm drink. As they drank, they watched the students wend their way up valley some hundred metres below their position.
Eric Dafoe was in attendance at the CMH training last December. Eric’s the senior Park warden at Rogers Pass and explained what happened next. Nearly a year after the incident, no one’s certain what exactly lit the fuse on that February morning. Visual inspections conducted by helicopter, when the weather cleared enough to safely fly a couple of days later, revealed a medium-size chunk of cornice missing from the ridge below the peak of Cheops Mountain. Best guess speculation is that it might have broken off, dropped down high in a chute on a 45º slope and propagated a fault along one of the shallower weaknesses in the snow pack.
Whatever the precipitating event was, what happened next still leaves Eric misty-eyed and a bit numb whenever he talks about it. According to Bruce Allen’s technical report, commissioned by the B.C. Coroners Service, the avalanche ran down a wind-loaded gully on the northwest aspect of Cheops below the cornice. In addition to being in the lee of the prevailing winds, the gully was also cross-loaded from the west. The snow fractured for a distance of 100 metres. Additional fracture lines propagated diagonally – and into the deeper instabilities – down the ridge to the west of the gully for another 183 metres. Average depth of the fracture was 2 metres.
Picking up speed and volume, the snow stepped down to the ice layer of November. Seconds after hearing a loud "crack", Rich Marshall was on his feet yelling to the students below, "AVALANCHE! AVALANCHE! AVALANCHE!" By the time most of them spotted it, the air blast was already hitting them. They didn’t have a chance.
Bruce Allen measured the distance from the highest fracture line to the runout on the valley floor at about 800 metres, eight-tenths of a kilometre. The incline – 45º more or less – didn’t appreciably decrease until the base of Cheops met the valley below.
The wall of snow hit the valley floor at nearly 180 kilometres per hour.
The top of the avalanche (west end) filled the valley floor and ran some 40 metres up the other side of the slope into the trees at the bottom of Hospital Gully, leaving a deposition of two metres. Snow carried on the wind blast dusted Rich and Abby still higher upslope. The volume of snow sliding off Cheops and the momentum was great enough that the centre of the avalanche ran up the opposite side of the valley and turned down valley where it ran another 400 metres before coming to a silent stop.
The total deposit in Connaught Creek Valley was 740 metres long and averaged 85 metres wide. Average depth was 2.5 metres and maximum depth, 5 metres.
There’s no way to know how many people would have died had Rich and Abby not stopped for tea when they did. Chances are pretty good the toll would have been much greater than it eventually was since they managed to methodically dig out five students.
That’s because the two of them were trained mountain guides. They’d done the study, gained the experience, knew the drill. They’d bridged the gap between knowledge and application. And this was most certainly application.
They skied down to the top end of the avalanche where they could see the exposed arm of one of the group. As luck would have it, the partially buried skier was Andrew Nicholson, one of the teachers guiding the group. They freed him enough to allow him to dig himself out and proceeded in an orderly way down the debris field. They dug where they saw signs – gloves, hats, poles – and where they got positive hits on their avalanche transceivers, now set to receive the multiple signals coming from beneath the snow.
They worked fast but methodically, digging just deep enough, through snow that had set up like cement, to uncover the faces of four students who had been near the front of the group, then moving on.
Andrew Nicholson, having freed himself, dug a satellite phone out of his pack and called the Rogers Pass warden’s office. "We need help, please!", he cried into the phone. It was 11:50 a.m., five minutes into the drama.
Dale Roth, the other teacher, the chaperone and two students were at the back of the group. They were carried down valley nearly 200 metres and partially buried. They managed to free themselves and started working up the debris field, searching for missing students.
Forty minutes after Cheops slid, 10 more rescuers were on the scene, then 30, then 40. Being in the heart of B.C.’s adventure travel country, mountain guides flew in from nearby heli operations almost immediately, including Ruedi Beglinger.
It was all over within an hour and 20 minutes. Seven students weren’t reached before they suffocated in their icy prisons. Everyone who’s studied the event knows that number would likely have been 12 if fate hadn’t put Rich and Abby close enough to see something they wish they’d never seen.
Terrain is the Problem; Terrain is the Solution
It wasn’t until sometime late in the third day that I finally began to understand what was going on at guide training. Partly because it wasn’t at all what I was expecting, partly because I was star-struck. Not by the guides, by the people there presenting and leading discussions.
The first evening a scholarly looking, bespectacled man stood at the front of the group and began talking about fracture propagation and resistance in weak snowpack layers. He was proposing a new classification system for describing the way a column of snow breaks off and slides during a field compression test. It was dry stuff.
But when Bruce Jamieson talks, people listen. Bruce runs the University of Calgary’s Avalanche Research Program. I’d been reading his stuff since Anton Horvath, one of Whistler’s avalanche forecasters, inferred he’d be willing to waste his time talking to me about avalanches a number of years ago but it might be a good idea if I knew a bit about the subject first. Bruce’s many papers and monographs were a good place to start.
Anton also recommended The Avalanche Handbook by David McClung and Peter Schaerer. It’s been the avalanche text for people who want to both travel and return from snowy backcountry for the last 30 years.
So naturally I was pretty wowed when a bald, nebbishy looking guy stood up and started speaking on the application of fractal geometry in guiding. Fractal geometry? Fractal geometry had barely been "discovered" in 1970 when Dave McClung wrote his book and here he was, in the flesh, reminding us all that Euclid, for all his insight, had only scratched the surface.
And Peter Schaerer, looking every bit like everyone’s wizened grandfather, was sitting in the front row nodding his head in agreement!
I’m pretty sure there were maybe only a dozen people in the room who had ever heard of fractal geometry and I’m equally sure there were only three who understood the math Dave was scratching out on the overhead projector.
One of those three was, well, indescribable is probably the best description. If Tim Burton, the film director, were to decide to remake Heidi , he might cast this guy as Grandpa. His face was ringed by wild, grey hair. It was hard to know for sure where his head hair left off and his beard hair began. The whole wreath stood out perpendicularly from his head as though he were his own static electricity generator.
Speaking mainly in Swiss German with occasional forays into English, Werner Munter would have been fascinating had he been presenting a wine list. What he was presenting though was his 3x3 Reduction Method for determining slope stability and making Go-No Go decisions. His method is de rigueur in the European alpine community but has met with considerable resistance in North America, where he’s better known in the climbing community for his Munter hitch belay method.
The parade went on all week. Manuel Genswein, who probably knows more about using avalanche transceivers than anyone in the world, attended from Switzerland to instruct in efficient search techniques for multiple burials. To drive his points home, he conducted timed field tests with five buried, remote-controlled "victims" arrayed across a field 50x50 metres. Humbling.
Bruce Jamieson explained part of what was going on to me. "Avalanches are very complex phenomena. We’re a long way from understanding them. We’re making small steps towards improving the prediction of avalanches but they are still a poorly understood phenomena because of things like spatial variability. Being here, presenting to a group of people who live the phenomenon every day, strengthens our research because they’re quick to question the application of what we’re doing and through this exchange of ideas, we’re able to essentially field test what we’re doing in the lab.
"I think of a guide’s head, a forecaster’s head, as a very powerful, associative processor. All these bits of uncertain information that come in about the snowpack, they get through their skis, they get from the information exchange they get from their neighbours, they get from weather forecasts. Their inability to describe, to articulate that process is quite fascinating and yet, it works. There are very good decisions made by these people.
"It is humbling to be in a science where the best methodology has difficulty improving on these guys’ intuitive knowledge."
Intuitive, associative, whatever you call it, it is impressive to watch in action. Standing in a snowpit, watching the guides and Chris Stetham work the layers, I keep pestering them, not about what they’re finding, I’m finding the same thing. But about what it means . How their findings get translated into where they go and what they consider safe. It’s frustrating that they all seem so inarticulate about the meaning of what they see.
But maybe understandable. Decisions made in the field factor in a lot more information than snow observations. They embrace the whole weather history of the area since snow began to fly, recent storms, real-time weather, recent and historical slides, the "feel" of the snow and a guide’s gut, for lack of a better word.
And that – not the hokey-pokey – is what it’s all about. Snow doesn’t care what you know or who made the mistake. Snow’s not impressed with how smart you are or how many successful trips you’ve taken into the backcountry. Snow’s indifferent to the advances we’ve made, the insights we’ve gained into the science of snow, weather, physics and avalanche modeling. When the conditions are right – and there are so many right combinations – snow lets go.
So if you want to play safe in the backcountry, it’s good to know as much as you can about snow. It’s even better to be with someone who’s in it every day, all winter long. Ross Cloutier summed it up in his report to Strathcona Tweedsmuir School. "Local knowledge plays an important role in outdoor leadership decision making. A guide who works in a specific location throughout an entire season (or many seasons) and who knows the terrain intimately should be able to make more accurate decisions than a guide who is in an area for the first time (or occasionally)."
Play carefully out there.
