2021/12/11 - Washington - Silver Basin, closed portion of Crystal Mountain ski resort

Published 2022/01/16 by Andy Harrington and Dallas Glass - Northwest Avalanche Center

Conditions in the Silver Basin area were still considered early season at the time of the accident. Silver Basin is within the Crystal Mountain Ski Resort operating boundary, but this terrain was not yet opened, patrolled, nor mitigated for avalanches due to lack of snow cover. On Sunday, 12/12/21, the snow depth in a representative location of Silver Basin was found to be 162cm with a generally right-side-up snow profile. A layer of 1mm rounding facets was found at 32cm but cannot be confirmed as the weak layer responsible for this accident. This layer was above a knife-hard melt-freeze crust formed and buried on 12/8. The slope that failed was observed to be wind-loaded.

On the morning of December 11, a group of six ski tourers arrived together in the Crystal Mountain parking lot to ski in the Silver Basin area. The party took the approved uptrack through the open resort toward Silver Basin. As they left the confines of the operating ski resort, they broke trail and continued up into the basin instead of trending left toward the backcountry terrain away from the resort. The group decided to take a break on a knoll below the headwall of Silver Basin. At this point, some members of the party reported feeling uneasy about ascending the headwall toward the ridgeline. A brief discussion occurred and they decided to continue. 

As the team ascended the headwall via a long traverse, they continued to break trail and about 250 vertical feet below the ridgeline they saw cracking and “felt the snow change”. They turned back across the slope to the north, intending to find a place to transition for the ski down. At this point, all six members were close together when the slope avalanched. The entire party was caught, carried, and deposited in two groups of three. 

The upper three members of the group came to rest approximately 200 vertical feet below the trigger point. Of this group, skiers 1 (not critical) and 3 (critical) were partially buried, while skier 2 was fully buried.

The other three members of the group were deposited approximately 350 vertical feet below the trigger point. Of this group, skiers 4 and 5 were fully buried, while skier 6 was partially buried (not critical). Skier 4 was swept through a tree island and over a small cliff during the descent.

Because the party was deposited into two separate groups, the ensuing rescue occurred in two stages. In the upper party, skiers 1 and 3 were able to free themselves, locate each other and begin searching for skier 2. Skier 3 called 911 and was patched through to Crystal Mountain Ski Patrol who assisted via telephone with best practices during a rescue. Skier 2 was located by skier 1’s transceiver and probe within minutes. Skier 2 was less than a foot below the surface, was quickly excavated and found to not be breathing, but did have a pulse. After clearing the snow from his face and rolling the skier over, skier 2 began breathing and was left to recover as skier 1 and 3 searched for other members of the party. 

Simultaneously, rescue efforts were underway with the lower group. A nearby party of two had witnessed the accident. Witness 1 stayed in a safe zone and called 911 while witness 2 rushed to assist with the rescue. Skier 6 was able to self extricate and immediately began a transceiver search, quickly locating skier 5, who was fully buried, but had a large air pocket. Witness 2 confirmed verbally that skier 5 had an airway and then directed his attention toward finding other members of the involved party. Witness 2 located skier 4 by using a visual clue of a backpack hanging in a tree and then focussing his beacon search fall line from the backpack. Skier 4 was found fully buried about a foot below the surface and upon extraction deemed to have obvious trauma, no pulse, and was not breathing. After clearing the airway of snow, CPR was performed by witness 2 where a soft thorax was noted. Witness 2 terminated CPR after a few minutes, thinking that 3 other individuals were still missing. At this time, skier 6 had gotten skier 5 to the surface, who was unharmed. Witness 2 started to proceed uphill where verbal contact with the upper party was established and it was determined that all involved individuals were accounted for and unharmed. Skier 4 was presumed dead by the group due to obvious trauma and lack of responsiveness to CPR.

At this point, a decision was made to exit the scene to a safer location and all individuals, apart from skier 4, descended toward the treeline to regroup. Around this time, volunteers and Crystal Mountain Ski Patrol arrived at the accident site. The scene was evaluated and Crystal Mountain Ski Patrol recovered skier 4 while the involved parties were escorted back toward Crystal Mountain Resort to debrief. 

NWAC staff and Crystal Mountain Ski Patrol returned the following day, Sunday December 12, 2021 to conduct an accident investigation and take additional photos. Stormy weather on the day of the investigation limited access to the crown and hampered information gathering. 

Silver Basin is within the Crystal Mountain ski area boundary and during full operations is regularly mitigated for avalanches by the Crystal Mountain Ski Patrol. On the day of the accident, a significant winter storm was set to impact the region. Due to low snow coverage prior to this storm, Crystal Mountain Resort was not running at full capacity, thus Silver Basin contained backcountry conditions at the time of the accident. Physical signs enroute to Silver Basin and information on the resort’s website disclosed the resort’s uphill travel policy, avalanche mitigation plans, and terrain closures. A special statement in the NWAC avalanche forecast conveyed that you could encounter backcountry snowpacks in pre-season ski area terrain. The group involved in the incident did not check in with Crystal Patrol on the day of the accident but they were aware that an uphill travel policy existed.

One member of the party frequently traveled in Silver Basin while others were not as familiar with the area. Some members of the group reported deferring to the more experienced friend for decision-making about terrain choices. This may have been a factor in the decision to climb the final headwall where the avalanche occurred. Members of the group reported feeling uneasy about the decision after noticing blowing snow and generally stormy conditions but did not speak up about their concerns. Despite the one member’s knowledge of the terrain, the obtained GPS track shows that the party traveled under multiple larger avalanche paths as they ascended.

Witnesses reported that as the party ascended the headwall, they were bunched very closely together, almost tip to tail. Just before the avalanche occurred, the group reportedly noticed changing conditions and made the decision to abandon their ascent to the ridge. They attempted to find a location to transition and descend when the avalanche occurred. Traveling closely together was likely a factor in all six members being caught in the avalanche. Had they been more spaced out, it is possible that only a few members would have been in harm’s way.

The small tree island and cliff played a key role in this fatality. The avalanche deposited the party into two groups and Skier 4 was unfortunately swept through this terrain trap. A medical examiner determined that multiple blunt force injuries were the cause of the fatality. In the same group, skiers 5 and 6 missed the knoll and came to rest near the toe of the debris unharmed.

As part of the interview process with NWAC forecasters post-incident, the group relayed that they had not thoroughly discussed the forecast hazard expected that day against their planned travel route/objective in Silver Basin. They were drawn to the area based on relatively good early season coverage, expected storm totals, and familiarity with the terrain.

NWAC report