Eleven skiers and four guides who were caught in a deadly avalanche after leaving their remote cabin near Donner Peak appeared to have chosen a route out of the wilderness where terrain was considered more dangerous than a longer, slower exit route, interviews and documents show.
Nine members of the group have been confirmed or suspected dead, including six female friends from the Bay Area, Tahoe and Idaho, and three employees of Blackbird Mountain Guides.
Based on where the disaster occurred, it appears the group left Frog Lake Lodge just before noon Tuesday and headed northwest along the Green Mountain Trailhead route, which ends on the north side of Interstate 80 across from North Mountain Resort. It was unclear where the tour guides and customers parked their vehicles.
The route traverses slopes as steep as 60 degrees and is rated “Complex” or “Level 3” on the avalanche terrain exposure scale, the second most dangerous score below “Extreme,” according to the Truckee Donner Land Trust, which owns the ski lodges. The scale, called ATES, was developed by Parks Canada and is widely used in the United States
Documents and maps show that east of the cabin is a longer, flatter route to Johnson Canyon, rated “easy” or “Class 1” on the land trust website. The lowest level is “Level 0,” which describes “no known avalanche exposure.”
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The avalanche, about 100 yards wide, occurred near the start of their trip out of Frog Lake, where they had enjoyed three days of backcountry skiing before a huge storm hit.
The Nevada County Sheriff’s Office said it is investigating why the group decided to risk the extreme weather rather than stay in the cabin and whether criminal negligence was a factor in the tragedy. On Thursday, the state’s workplace safety agency, the California Occupational Safety and Health Administration (Cal/OSHA), said it had launched a separate investigation into Blackbird Mountain Guides as authorities attempted to recover the bodies of victims amid the ongoing storm.
The family of the deceased issued a statement on Tuesday saying they had “many unanswered questions.”
“Eight close friends planned a two-night, professionally guided backcountry cabin trip to Frog Lake Lodge outside of Truckee, California,” the statement said. “The trip was organized in advance. They were all experienced backcountry skiers with a deep respect for the mountains. They were trained and prepared for backcountry travel and trusted their professional guides on this trip. They were fully equipped with avalanche safety equipment.”
Neither the tour guide company nor the nonprofit land trust immediately responded to questions about the route sent by The Chronicle.
Zeb Blais, founder of Blackbird Mountain Guides, said in a statement, “Field guides are communicating with senior guides at our base to discuss conditions and plan routes based on conditions. We are still learning what happened. It is too early to draw conclusions, but the investigation is ongoing.”
Jim Zellers, a frequent visitor to Frog Lake, said in an interview that given the limited information available, it’s unclear whether the guides made the mistake of choosing the westward route. The backcountry snowboarder said that ideally, someone experiencing such severe weather would stay in a cabin and wait, but added that there may be extenuating circumstances.
Which exit to choose depends on a variety of factors, including the direction of the storm, guests’ conditions and familiarity with the route, he said.
“You can’t start judging,” said Zellers, who has visited the cabins about 40 times and helped build some of the furniture. “It’s a scary place. Those of us with more experience are just sad, and those with less experience are judging.”
He noted that while the Johnson Canyon route has less avalanche risk, it can be more difficult to navigate, especially in whiteout conditions and if the guide is not used to traveling in that direction.
The land trust that rents the cabins has a page on its website dedicated to winter trails. “All routes listed in this guide involve some degree of avalanche danger,” the website warns.
It advises skiers to check each route’s avalanche terrain exposure rating and monitor daily avalanche forecasts. The Sierra Avalanche Center issued an avalanche warning around 5 a.m. the day the group left the cabin.
From the cabin, the Green Mountain Trailhead is three and a half miles away, with an ascent of 1,100 feet and a descent of 1,500 feet. In the first section near the “gap” there is avalanche terrain on both sides.
“Some avalanche terrain is often affected by wind, with large cornices on the ridge,” the trust explains. The next section is below the Frog Lake escarpment and includes a number of avalanche paths. “Appropriate avalanche conditions must be present to traverse this terrain,” the trust said.
This trail can also take hikers to the Donner Peak Rest Area at the end of the return trip, but the dangerous sections are the same.
Another option is to head east on the 4.5-mile Johnson Canyon route. The trust said skiers would encounter some slopes on the first stage of the descent, but explained these were not as steep and consistent as the route to the west.
“Isolated pockets of avalanche terrain may be encountered through this section, but with careful route finding, most avalanche terrain can be avoided with limited exposure,” the trust writes. The site adds that much of the final stage of the route is below treeline and in “low-angle terrain.”
According to the American Avalanche Association, the simple Class 1 designation means “exposure to low angle or predominantly forested terrain.” “Some forest clearings may involve escape zones for rare avalanches and may contain terrain traps. There are many options for reducing or eliminating exposure.”
Meanwhile, the complex Class 3 designation refers to “exposure to multiple overlapping avalanche paths or large expanses of steep, open terrain. Continuous exposure to overhead hazards. Numerous avalanche initiation zones and terrain traps with few options to reduce exposure.”
This article was originally published on Skiers caught in deadly Tahoe avalanche appear to have chosen route rated most dangerous.