CAIC: Colorado Avalanche Information Center

2011/01/17 - Colorado - "High Trail Cliffs," northeast of Berthoud Pass

Published 2011/01/30 by Spencer Logan - Forecaster, CAIC


Avalanche Details

  • Location: "High Trail Cliffs," northeast of Berthoud Pass
  • State: Colorado
  • Date: 2011/01/17
  • Time: 1:30 PM (Estimated)
  • Summary Description: 1 snowboarder (and dog) caught, buried, and killed
  • Primary Activity: Backcountry Tourer
  • Primary Travel Mode: Snowboard
  • Location Setting: Backcountry

Number

  • Caught: 1
  • Partially Buried, Non-Critical: 0
  • Partially Buried, Critical: 0
  • Fully Buried: 1
  • 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: I - New/Old Interface

Site

  • Slope Aspect: NW
  • Site Elevation: 11300 ft
  • Slope Angle: --
  • Slope Characteristic: --

Avalanche Comments

Snowfall and drifting snow obscured the avalanche crown and debris. The dimensions given are estimates from rescuers on scene. The avalanche ran in the “Fingers”, a couloir on the northeast edge of the “High Trail Cliffs,” starting on a northwest aspect around 11,300 feet. The avalanche was probably less than 2 feet deep, involving only the new snow, about 200 feet wide, and ran about 300 vertical feet. It was small relative to the avalanche path (R2), and capable of burying a person (D2).

The riders triggered the fatal avalanche at the beginning of a natural avalanche cycle. Over the next several days, many natural avalanches ran from east and southeast starting zones above tree line, but only a few triggered or natural avalanches ran on westerly aspects.

Weather Summary

Snowfall started around 0500 on January 17. The Berthoud Summit SNOTEL site, approximately 0.5 miles west of the accident site, recorded 0.9 inches of water equivalent and 16 inches of new snow by 1300. Recent westerly and northwesterly winds had drifted large amounts of snow near and above tree line. The CAIC’s Berthoud Pass weather station, approximately 0.75 miles west of the accident site, recorded sustained northwesterly winds between 20 and 40 miles per hour, with gusts to 80 miles per hour.

Snowpack Summary

Approximately 16 inches of snow fell in the 6 hours prior to the accident. This period of heavy snow rapidly loaded the northwest aspect where the avalanche occurred. The avalanche was probably a storm slab that broke either within the new snow layer or at the interface between the new snow and old snow surface. A persistent weak layer did exist within the snowpack at the time of this accident. However, an avalanche that broke down to this layer would have been a much larger slide.

Events Leading to the Avalanche

A pair of snowboarders and one dog pair left Berthoud Pass and headed northeast. They took a high traverse below the “High Trail Cliffs.” They intended to reach the tree-covered ridge between the Cliffs and the Mines avalanche paths, ride the ridge, and exit out the Sevenmile ski trail. They were near the northeast edge of the Cliffs when they triggered the avalanche. The time was shortly after 1300.

Rider 1 was about 50 feet ahead and slightly below Rider 2 and his dog. Rider 1 noticed that the slope “broke up” around him, a bit like a “moving carpet.” He turned straight down hill, outran the avalanche, and stopped at the trees. He saw no sign of Rider 2 or the dog, and assumed they had outrun the “small” avalanche and were in the trees below him. Rider 1 descended to Highway 40 hoping to catch up with his friend.

Accident Summary

Rider 2 was buried face down and head pointed downhill. His head was under about 18 inches of avalanche debris. His dog was buried next to him. It appeared that Rider 2 took a diagonal descent when the avalanche started. He was caught and buried at the toe edge of the debris and may have been very close to outrunning the avalanche.

Rescue Summary

Highway 40 over Berthoud Pass closed mid-morning Monday because of inclement weather and avalanche conditions. CAIC highway forecasters were helping evacuate riders from the Pass. A CAIC forecaster spoke with Rider 1 a few minutes after he reached the Highway. Rider 1 said the pair became separated, and he would wait for his friend.

About an hour later, Rider 1 accepted a ride from the CAIC forecaster to the top of the Pass. He made two runs through the area looking for his friend. The CAIC forecaster picked him up after the second lap. At that time, Rider 1 mentioned that there had been a “small” avalanche. The CAIC forecaster suggested Rider 1 call 911 and notify them of the missing Rider 2.

At 15:10 Rider 1 called 911 to report his missing friend. Grand County Search and Rescue (SAR) mobilized and had hasty teams in the field by 17:30. They suspected avalanche, but included the possibility of a lost or injured rider. One team went up the Sevenmile trail. Another hasty team came in from Berthoud Pass, after the Colorado Department of Transportation (CDOT) plowed a single lane to the Pass for SAR access. Searchers checked tree wells and did a hasty search (including beacons) of avalanche debris that that night.

SAR returned to the scene on Tuesday January 18. A small group of community members equipped with avalanche safety gear, many friends of the victim, offered to help. In an unusual move, SAR incorporated the outside help. Additional snow and wind drifting obscured the avalanche debris, and SAR were unable to determine an exact search area when arrived below the High Cliffs. They used probes to feel out the approximate edges of the debris. A coarse probe line worked much of the search area on Tuesday. Winter Park Ski Area provided a RECCO receiver to search the debris.

SAR returned to the field on Wednesday. The community volunteers swelled to almost 50 people, and Alpine Rescue, Winter Park Ski Patrol, and Powder Addiction provided trained searchers. Probing resumed, and they found the victim mid-morning near the edge of search area.

Comments

The riders made several decisions, deliberate or otherwise, that led to a tragic outcome. They chose to ride without avalanche safety equipment, ventured into avalanche terrain, and did not use safe travel techniques for moving through avalanche terrain. However, many people make similar decisions with little consequence, especially at busy roadside areas like Berthoud Pass. Rider 2 was probably close to outrunning the avalanche when it caught him. A second faster, a few feet further on, and maybe it would have been a scary escape and not a tragic event. The line between the two outcomes can be very narrow.

Neither rider was carrying avalanche safety equipment. Rider 2 left his in the car because Rider 1 did not have a beacon, shovel or probe. Rider 2 did own, but was not wearing, clothes with RECCO reflectors.

Avalanche safety equipment is not a magic shield that prevents avalanche fatalities. About half of the people who are recovered from avalanche debris with beacons are found dead. However, venturing into avalanche terrain without safety gear is like removing the seatbelts and airbags from a car. There is no safety margin if a crash happens. In this case, only one rider—Rider 2—had avalanche safety equipment. Even if he realized his partner was buried, Rider 1 was unable to search. The outcome of the avalanche would have been the same, but the search and rescue time, and exposure of the rescue workers, could have been cut from three days to one afternoon.

Backcountry travel without avalanche safety equipment requires careful route finding to avoid all avalanche terrain. Rider 1 told rescuers that the pair felt safety equipment was unnecessary because “they only rode in the trees.” There are plenty of areas that are not exposed to avalanches around Berthoud Pass, but the High Trail Cliffs and Trees regularly produce avalanches. From the Pass, it is hard to reach the ridge between the Cliffs and Mines without traversing through avalanche terrain. Treed areas do not guarantee safety from avalanches, either.

On the morning of January 17, the CAIC forecast was for danger “will rise to HIGH (Level 4) on N-NE-E-SE aspects near and above treeline. The danger is CONSIDERABLE (Level 3) below treeline on N-E-S aspects and near and above treeline on S aspects. It is MODERATE (Level 2) on all other aspects and elevations. Snowfall is forecast to ramp upwards today. Expect an increase in avalanche activity.” An Avalanche Watch was upgraded to a Warning that afternoon.

The High Trail Cliffs are near treeline, though low in elevation, with northwesterly aspects. The riders were in terrain with a MODERATE (Level 2) rating. A MODERATE danger means “human-triggered avalanches are possible,” and “small avalanches may occur in specific areas.” Unfortunately, they traversed across rapidly loaded, obvious avalanche terrain and triggered an avalanche. In Colorado, more avalanche fatalities occur on slopes with a MODERATE danger than other danger ratings.

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