A skier who ducked a patrol closure January 3 was caught in the first in-bounds avalanche at Marmot Basin in seven years.
The incident took place on Party Slope, a rocky terrain feature on the upper mountain which, because of the unpredictable nature of the snowpack, released a class two slide even after technicians performed avalanche control work on the slope.
“The control work that day was aggressive,” said Marmot Basin’s Director of Public Safety, Kerry MacDonald. “[But] the snowpack this season across the Rockies is very weak at its base.”
That day, avalanche control staff at Marmot Basin were dealing with 32 cm of new snow, plus an additional six centimeters before the Knob Chair opened.
That type of aggressive loading on a weak snowpack is “like building your house on top of marbles,” MacDonald said.
In that regard, forecasting avalanches on Party Slope, with its large rock outcrops acting as anchor points and yet containing unpredictable trigger points all throughout the feature, was made even more challenging.
“We know that at the top it’s thin and weak and below the ridge crest it’s very rocky. It’s a great hazard to riders.”
And although a patrol sign said as much, at 3:10 p.m. a group of four skiers crested the ridge above Party Slope.
The first skier descended, rode through the rocky section and made a left turn. That’s when the slope released.
“He was carried for about 15 metres and ended up on the side of the slide,” MacDonald said.
Buried up to his waist and unhurt, the skier was able to free himself and walk down. The rest of his group met him at the bottom.
Meanwhile, ski patrol was calling “code white.” One patroller had witnessed the incident from the Eagle Ridge chair; another off-duty patroller was able to communicate to the involved party and determine there was only one victim.
Within five minutes several ski patrollers were on scene; in less than five more minutes a Canadian Avalanche Rescue Dog Association team showed up to do a final sweep.
“For an organized response it was exceptionally fast,” MacDonald said.
The last in bounds avalanche at Marmot Basin took place in 2006, in Knob Bowl.
“We work very hard to mitigate avalanche hazards and other hazards,” MacDonald said. “But there are inherent risks you accept as a rider to participate in this activity.”