CAIC: Colorado Avalanche Information Center

2010/12/05 - Colorado - Dry Gulch-East of Eisenhower Tunnel

Published 2010/12/31 by Scott Toepfer - Forecaster, CAIC


Avalanche Details

  • Location: Dry Gulch-East of Eisenhower Tunnel
  • State: Colorado
  • Date: 2010/12/05
  • Time: 11:30 AM (Estimated)
  • Summary Description: 2 skiers caught, 1 partially buried, 1 buried and killed
  • Primary Activity: Backcountry Tourer
  • Primary Travel Mode: Ski
  • Location Setting: Backcountry

Number

  • Caught: 2
  • Partially Buried, Non-Critical: 1
  • Partially Buried, Critical: 0
  • Fully Buried: 1
  • Injured: 1
  • Killed: 1

Avalanche

  • Type: HS
  • Trigger: AS - Skier
  • Trigger (subcode): u - An unintentional release
  • Size - Relative to Path: R3
  • Size - Destructive Force: D3
  • Sliding Surface: O - Within Old Snow

Site

  • Slope Aspect: N
  • Site Elevation: 11600 ft
  • Slope Angle: 35 °
  • Slope Characteristic: Gully/Couloir

Avalanche Comments

A good example of a cross loaded slope. The western flank ran along a ridge with numerous spruce trees and krumholtz islands which acted as a snow fence. This allowed the western flank to accumulate the deepest snow deposits. Strong and persistent westerly winds in this area allowed deposits on the bed surface to grow to the deepest depths along the western flank. The eastern flank feathered out into rocky terrain with minimal snow coverage which was mostly faceted snow and depth hoar.

Weather Summary

The nearby Loveland Pass weather station from 10 am to 3 pm on 12/5/2010: Temperatures rising from 21F to 23F. Winds were from the west-southwest 10 to 16 mph with a high gust of 31 mph at 3 pm. At nearby Berthoud pass from noon to 3 PM: Temperature a steady 19F. Winds were stronger from the west-northwest 28 to 39 mph with a peak gust of 44 mph.

Snowpack Summary

The crown profile showed a crown height varying from 30 cm to 125 cm in depth. A thin fist hard faceted layer was sandwiched between a one finger hard bed surface and a one finger hard wind slab. The slab stepped to the ground about 25 vertical feet below the crown.

Events Leading to the Avalanche

Subject 1 had some background with the Dry Gulch area. They had ski patrolled at Loveland Basin for a few years and this was one of the areas Subject 1 had explored. Subject 1 checked the avalanche advisory on Saturday, Subject 2 had checked it Sunday morning. They were both regular users of the avalanche forecast. Both members of the party broke trail up the eastern or climbers left side of the north-northeast aspect slope. They had looked at a few other lines but either did not like the terrain or there were other groups in the vicinity. Once they got to treeline they moved a little further west to look at a different line around a treed ridge. This path was well scoured from wind and did not have much snow coverage. Both decided to return to the original route. At the top both parties made a plan and reviewed potential safe spots. Subject 1 made a ski cut across the top of the path heading east, across a convex wind roll. Subject 1 stopped at an apex of their up track and turned to signal Subject 2 that it felt ok and they could descend to the pre-determined safe spot. At this pre-determined safe spot, Subject 2 stopped and turned to watch Subject 1 begin their descent a little further to skiers right of Subject 2's line and close to the center of the path. This area had a shallower snowpack depth when compared to the further west line taken by Subject 2. As Subject 1 descended to just about even with Subject 2, Subject 2 heard a loud boom and watched the slab buckle and break into refrigerator sized blocks.

Accident Summary

Subject 2 was caught in the slide and quickly lost site of his friend and also tried to escape further into the treed ridge to the west, but did not make it before being swept up in the debris. Subject 2 quickly lost both skis (AT set-up) and began to tumble down slope with the slab. At some point Subject 2 found himself under the snow with his head uphill. He had an Avalung which was partially in his mouth when he came to. He had a small air pocket and was able to move an arm and begin digging his way out of the debris. Subject 2 did not know if he was completely buried, as he was somewhat dazed after being swept through multiple small Sub-alpine fir and Engleman spruce saplings. Upon escaping the debris Subject 2 called for Subject 1 with no response, and not knowing whether Subject 1 was above or below began a beacon search uphill first.

Rescue Summary

Finding no signal going uphill Subject 2 started to search downhill, constantly yelling and hoping for a response. Subject 2 got a faint signal, which they lost but quickly regained and bracketed down to a lowest signal distance of 2 meters. This is where Subject 2 pulled out their shovel and probe. After 2-3 probes Subject 2 had a strike and began to dig. Subject 1 was buried an estimated 2-3 feet deep at the head. Subject 1 was buried with their head down-slope and on their side. The Avalung pack had been stripped from the shoulders but was still attached at the waist belt and the mouth piece was no longer available to use. After clearing the airway and starting CPR Subject 2 continued to yell for help, and maybe 15 minutes later an off duty Emergency Room Physician arrived on scene.

Comments

Subject 2 estimates it took 10 to 15 minutes to pinpoint, probe and begin excavation to Subject 1 after digging himself out (Subject 2 burial time is unknown). The probe strike hit Subject 1's arm and it only took a few shovel digs to get to the shoulder and then the top of the head. Then another 5 to 10 minutes more to excavate Subject 1 far enough to start adequate CPR. And then another 2-3 minutes to get Subject 1 into position to perform CPR. Subject 2 does not have a clear recall on the time elapsed from the start of the slide until he dug himself out of the debris. Approximately one half hour elapsed from the beginning of the search before Subject 1 was excavated and full CPR began.

Media

Images

Snowpits

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Figure 14: Fracture line profile observed on December 6th above the crown face on the east side.