It’s one of North America’s most volatile mountain passes and it’s Robb Andersen’s job to make sure public safety is the first priority. A day in the life of this Kootenay Pass avalanche forecaster is  one of snow

It’s one of North America’s most volatile mountain passes and it’s Robb Andersen’s job to make sure public safety is the first priority. A day in the life of this Kootenay Pass avalanche forecaster is one of snow

Bringing down a mountain: a day in the life of an avalanche tech

  • Feb. 17, 2011 3:00 p.m.

The air at the top of the Kootenay Pass is choked with white fog, punctuated with a thin but constant stream of snow. Though forecasts have called for fair weather and clear skies, they haven’t shown up since Robb Andersen began his day at 7 a.m.

No matter. From his well-insulated office more than 1,700 metres up the mountain, Andersen has control of an arsenal. Twenty-two gas powered guns wait only for his signal. Each has the potential to bring about an avalanche.

In the last month, Andersen and his team have used them to bring down the mountainside more than two dozen times. When necessary, they’ve supplemented them by chucking 25 kg bags of explosives out the side of a helicopter.

For most people, Andersen’s day job is the stuff of action movies. For this avalanche technician, it’s just another day at the Ministry of Transportation.


Born in Banff to a family of avid skiers, Andersen says working in the mountains was inevitable.

“I’ve been in a mountain environment my whole life,” he says. “I’ve been a skier since I was a little kid. It’s in my history.”

In the early 90s Kootenay powder lured him west, and what was originally intended to be a short gig as a ski patroller at Whitewater turned into a full time job. By the time a job opened up on the team at Kootenay Pass, he’d become a ski forecaster and worked with avalanches for more than a decade.

Today, he’s the manager of the a five-man forecasting team responsible for monitoring and controlling the avalanche hazard on the highest pass in the country that’s open year-round. While his office is tucked out of sight of the highway, one knows he’s at work by the piles of snow and debris pushed to the side of the roads and the two hour closures that can turn driving the pass in winter from a time saver to a good time to clean out the glove compartment. Twice.

Though the stretch of Highway 3 Andersen now oversees was built in the 50s and 60s, “they weren’t thinking avalanche problem,” he says. “They didn’t do any work up here in the winter, and every spring they’d come up and go ‘wow, there’s a lot of snow at the gate.’”

All that changed in 1976, when three people were killed by an avalanche while driving the western half of the pass. In the same year, another slide took out a cafe in Terrace, and the province launched its first three avalanche control centres, including one at Kootenay Pass.


There are several things that make the pass difficult to keep clear and safe in winter, but they all seem to boil down to location and snow.

“It only takes about 20 cm of snow — depending on conditions, let’s say 15 to 30 cm of new snow — and we have to close the highway and do avalanche control. That’s a big enough snowfall for us to have an avalanche problem to effect the highway,” says Andersen.

On a typical January day, 20 cm of snow can pile up in as little as four hours. When storms hit the pass — as one did at the beginning of February — Andersen can spend days at a time in the office, grabbing two to four hours of sleep a night between monitoring, reviewing weather data and driving the highway to assess conditions firsthand.

The weather also makes “heli-bombing” at best a weekly activity. Most days the visibilty’s simply too bad to fly, or drop explosives with the kind of necessary accuracy.

As for location, were this stretch of Highway 3 to be built today, it seems unlikely it would end up in the same spot.

“They built the highway right in the middle of the avalanche track,” Andersen explains.

“If they’d put the highway on the other side of the valley, I wouldn’t even have a job, because there are no avalanche paths on the other side of the valley… They just put it on the south side because that’s where it catches the sun. That was the thinking about it.”

Even a mile down the mountain would make a difference, he adds. With the road so far up, small avalanches have the potential to do far more damage.


Andersen’s days begin in the weather plot, a roped off patch of snow the size of an ambitious backyard garden. While most avalanche control sites rely on computerized weather information, the relatively small size of the Pass allows the team to maintain one of the few manual observation plots in the province.

Here, Andersen and assistant forecaster Mark Talbot check the air temperature (about -12 on this day), the density of the snowpack and the latest snowfall. Talbot descends into a pit dug in the snow to carve a fresh block of white out of its side, which is tilted on a platform to see how the latest powder is bonding with the lower layers of the snowpack. Similar tests take place on the mountainside itself.

Despite the foggy conditions, Andersen says it’s looking like a decent day from an avalanche control perspective. Only a few new centimetres of snow have piled up so far, “and if we do get any avalanches, they’re going to be very small.”

The rest of the day is dedicated to monitoring, driving and — if necessary, firing off a selection of 22 canons that make up the Gazex System.

“The Gazex system is awesome,” says Anderson. “It’s super reliable and we can shoot it 24/7… If we didn’t have the Gazex and we had the weather like we had today, where we can’t fly, we’d just have to close the road and wait.”

Unlike heli-bombing, which require up-close explosive deployment, the Gazex is remotely controlled from a laptop. To fire, all Andersen has to do is “punch in the firing codes and hit return.” A mix of propane and oxygen flow into the mountainside guns, which is triggered by a 1,300 volt spark.

“It’s kind of like lighting a barbeque with the lid down after you’ve let the gas build up,” Andersen says.

While one forecaster fires the canons another is out on the road, under the avalanche, ensuring the blast has done its job. And while driving is, in Andersen’s opinion, the most dangerous part of the job, there’s clearly a rush to standing in the path of all that falling snow.

“I love starting avalanches,” he says, with a chuckle and a shake of his head.

“Avalanche forecasting is not an exact science, there is some variability there. A lot of it depends on the weather. So when you do get the results you’re expecting, it’s very satisfying. And it’s really neat to watch.”

There’s another benefit to the job as well. As the fog finally starts to clear in the early afternoon, Andersen heads out past a line of stopped cars to check on the progress of the road maitenance crew, which clears up both the avalanche debris he creates and the day-to-day snow on the road.

Though the snow is still trickling down, pockets of pale blue have started to appear in the sky and the pass is almost blindingly bright. Standing at the side of the highway, Andersen looks down the mountain and grins.

“It sure is a good office,” he says.