Lessons learned from Beehive Basin incident
By Emily Wolfe Explore Big Sky Managing Editor
Walk around in the mountains in southwest Montana right now, and you’ll likely hear and feel “whumphs” in the snowpack, the classic sign of a buried layer of surface hoar collapsing.
Formed during the January dry spell, this weak layer is widespread across the region. When it collapses, if the slope is steep enough, it avalanches. This can occur on relatively small slide paths, and even in the trees.
This is what happened on Feb. 16 when three Bozeman skiers triggered and were caught in an avalanche on a west-facing slope in Beehive Basin, north of Big Sky.
Having skied there before, the group was planning to gain the ridge between Beehive and Middle basins. When they realized they’d missed the standard skin track, which was buried beneath new, windblown snow, they began breaking trail up through the trees on their right, aiming to meet up with it.
“After a while, we realized this was not the right way,” said Rodrigo, age 37, and one of the members of the party who asked to be identified by his first name only. “We [were already] pretty high, but we figured we could make it to the ridge instead of turning around.”
Behind him were another friend who wanted to remain anonymous, age 40, and Rodrigo’s wife Melanie, age 35.
Speaking to Explore Big Sky via telephone on Feb. 17, Rodrigo said he hadn’t seen any signs of instability – shooting cracks, whumphs or other avalanches – although his two partners had seen a small, shallow slide cross their skin track that they didn’t consider a significant sign.
By the time they’d climbed to around 8,700 feet, the slope was getting fairly steep, Rodrigo said. “I heard a “whumph” and was going to turn back and say, ‘It’s sketchy,’” he recalled, “but that was the avalanche.”
It carried him about 10 feet before he grabbed a tree. Snow gushed past, but left him uninjured. When it was over, Rodrigo shouted his companions’ names. The other man had also been pushed into a patch of trees, and was also uninjured. They couldn’t see or hear Melanie so they took their skis off and started a beacon search downhill.
Eventually they heard her voice and found her about 150 feet downslope, buried up to her neck.
They dug her out at 12:45 p.m., but found she couldn’t put weight on her right leg, an injury she sustained from being swept into a tree. Without cell phones, they couldn’t call for a rescue, so Rodrigo skied out until he encountered another party, which called 911. Big Sky Search and Rescue responded with seven SAR team members, getting her to the trailhead by 4:30 p.m., where an ambulance was waiting.
The avalanche released 100 feet above Rodrigo and broke 50 feet wide, 18-24 inches deep and ran 300 feet vertical, according to a follow-up report by Gallatin National Forest Avalanche Center Director Doug Chabot. The slope angle was 36 degrees at the trigger point and 40 degrees at the crown. The debris pile was approximately six to eight feet deep and 40 feet wide.
He and Melanie have been skiing in the backcountry for five years and had taken an avalanche awareness course at MSU, he said. They had checked the avalanche report that morning and knew the danger level was rated considerable on wind-loaded slopes.
Rodrigo said he hopes others can learn from their story.
Because they had been walking through the trees, he said, they didn’t realize they’d entered an avalanche path. Also, he noted, westerly slopes aren’t typically wind loaded, although this one was.
“Yes, they were in the trees, but they were in an avalanche path,” Chabot told EBS after his investigation. One of the indicators he pointed out was that many of the trees were flagged, meaning they were missing uphill branches, having been broken by past avalanches.
“If you’re at the bottom of the slope and you see flagged trees, look uphill because that’s avalanche terrain up there. The same held [true] with this.”
Chabot also said the perception of trees as “anchors” for a slope is often misconstrued.
“If you can ski, zip around in the trees making turns, and it’s a steep slope, in the right conditions that will slide. It’s one of those things where you have to kind of see it to believe it.”
Avalanches – both human triggered and natural – have been reported throughout the Gallatin National Forest Avalanche Center’s advisory area so far in February. They have occurred up Taylor Fork, at Bacon Rind, and at Quake Lake, as well as in Cooke City where residents saw a natural slide run into town and deposit debris in their back yards, according to the Feb. 18 avalanche advisory.
With storms continuing to pummel the area with new snow and wind, the danger level is likely to remain elevated in most mountain ranges, Chabot said.
The sheriff’s office, which oversees the Gallatin County Search and Rescue teams including Big Sky’s, recommends each member of a backcountry party carry a cell phone as part of their rescue kit; however, these should be turned off at all times, because they can interfere with an avalanche transceiver’s search function.
Find the current avalanche advisory at mtavalanche.com.