CAIC

Avalanche Details

Location: Waterfall Canyon, south of Ophir
State: Colorado
Date: 2024/01/22
Time: Unknown
Summary Description: 1 backcountry snowboarder caught, partially buried, and killed
Primary Activity: Backcountry Tourer
Primary Travel Mode: Snowboard
Location Setting: Backcountry

Number

Caught: 1
Partially Buried, Non-Critical: 1
Partially Buried, Critical: 0
Fully Buried: 0
Injured: 0
Killed: 1

Avalanche

Type: SS
Trigger: AR - Snowboarder
Trigger (subcode): u - An unintentional release
Size - Relative to Path: R2
Size - Destructive Force: D2
Sliding Surface: G - At Ground/Ice/Firm

Site

Slope Aspect: NW
Site Elevation: 11475 ft
Slope Angle: 40 °
Slope Characteristic: Sparse Trees,Gully/Couloir

Avalanche Comments

This was a soft slab avalanche, unintentionally triggered by a backcountry snowboarder. It was small in size relative to the path and produced enough destructive force to bury, injure, or kill a person. It broke on a layer of depth hoar buried 12 to 28 inches below the snowpack surface and ran to the ground in many places. (SS-ARu-R2-D2-G). The avalanche was 40 feet wide and ran 650 vertical feet. It started on a northwest-facing, sparsely treed slope that was 40 degrees in steepness. The avalanche ran over a bench feature lower in the path. It stepped down to the ground again in the steeper terrain below the bench.

Backcountry Avalanche Forecast

The Colorado Avalanche Information Center’s (CAIC) forecast for the area around Ophir for January 22, 2024, rated the avalanche danger at Considerable (Level 3 of 5) near and above treeline, and Moderate (Level 2 of 5) below treeline where the fatal avalanche occurred. The primary problem was Persistent Slab avalanches on west through northeast to southeast aspects at all elevations. The likelihood was Likely near and above treeline and Possible below treeline. The expected size was Small to Large (up to D2). The summary statement read:

You can trigger a large and dangerous avalanche on steep slopes. Avalanches triggered from lower-angled terrain could propagate uphill, creating a broader, more destructive slide. Wind-loaded, easterly facing slopes have the deepest snowpack, and the largest avalanches observed on these aspects.

Stick to low-angled slopes and avoid terrain traps. Know what terrain surrounds you and give slopes steeper than 30 degrees a wide buffer. Four to six inches of snow expected to fall in parts of the forecast area Sunday into Monday. This will freshen the snow surface but doesn't change the overall avalanche hazard.

Snowpack Summary

November 2023, December 2023, and the first weeks of January 2024 were dry and cold. The snowpack in the western San Juan Mountains was shallow and faceted. A storm started on January 11. Eighteen inches of snow and 1.8 inches of snow water equivalent were recorded at the Lizard Head Pass SNOTEL station, located two miles southwest of the avalanche site at 10200 feet. This was only the third storm of the season with 10 or more inches of snow. On January 22, the Lizard Head Pass SNOTEL site was at 76% of the seasonal median for snow water equivalent. Overnight temperatures were well below freezing. Winds were light and variable on January 21 and 22.

The snowpack on the slope that avalanched was shallow and composed almost entirely of faceted snow grains. There was a 14 cm thick layer of chained depth hoar in the middle of the snowpack that developed during the prolonged dry period. Snow from the January 11 storm formed a 12 cm thick, very soft slab (4F on the hand hardness scale) of decomposing storm snow grains. The avalanche broke below the slab and gouged to the ground in most places. While winds were strong during snowfall and temperatures just above freezing in the days preceding the accident, neither played a significant role in forming the slab from the January 11 storm.

Accident Summary

Rider 1 traveled alone on the day of the accident. There were no witnesses to the avalanche.

Rescue Summary

Friends reported Rider 1 overdue on the evening of January 22. San Miguel Search and Rescue (SMSAR) flew an unmanned ariel system (aka drone) but were unable to complete a thorough search before nightfall. A friend of Rider 1 followed his tracks up a well-used route to the top of a frequently skied slope. The friend saw a single set of tracks descending the slope. It was too dangerous to descend, so he returned to Ophir.

On the morning of January 23, Telluride Helitrax flew SMSAR members into the area. They located Rider 1’s body from the air. SMSAR recovered Rider 1 that morning. Search and rescue efforts were led by the San Miguel County Sheriff’s Office and supported by San Miguel Search and Rescue, Helitrax, and the Colorado Avalanche Information Center.

Comments

All of the fatal avalanche accidents we investigate are tragic events. We do our best to describe each accident to help the people involved and the community as a whole better understand them. We offer the following comments in the hope that they will help people avoid future avalanche accidents.

Investigators reconstructed the avalanche events from site evidence. Rider 1 was descending the slope and probably triggered the avalanche high in the starting zone. The avalanche flushed him through a sparsely treed gully. The avalanche entrained snow and gained mass as it flowed over a bench lower in the track.

Rider 1 was partially buried near the toe of the debris. His snowboard was broken and he sustained traumatic injuries during the avalanche. Rider 1 freed himself from the debris but did not dig out his backpack and left his snowboard. He began to walk downhill, towards Waterfall Creek and Ophir. Rescuers found his body 500 to 600 feet below the toe of the avalanche.

Rider 1 was traveling alone. While traveling in a group provides more resources and additional rescue options if something goes wrong, traveling in the backcountry solo is a personal choice. Rider 1 was an experienced backcountry snowboarder, with a high risk tolerance. He was comfortable traveling alone and did so regularly.

It is possible a partner or a satellite communication device could have changed the outcome of this accident. In other accidents in the Ophir area (March 24, 2020, December 31, 2022), communication with other groups allowed community members and rescue teams to respond quickly.

Examining the cause of death in Colorado avalanche accidents, Sheets et al. (2018) found that trauma accounts for 30% of avalanche deaths. In the case studies, the trauma was typically severe and “likely to cause death rapidly.” In this case, Rider 1’s injuries were not immediately life-threatening. A partner may have been able to provide first aid, and communication may have brought help on the day of the avalanche. Alone, Rider 1’s injuries and exposure to the elements during a cold winter night became a fatal combination.