CAIC: Colorado Avalanche Information Center

2013/01/27 - Colorado - Kendall Mountain southeast of Silverton

Published 2013/02/09 by Scott Toepfer - Forecaster, CAIC


Avalanche Details

  • Location: Kendall Mountain southeast of Silverton
  • State: Colorado
  • Date: 2013/01/27
  • Time: 1:00 PM (Estimated)
  • Summary Description: 1 skier caught and buried/critical while ascending.
  • Primary Activity: Backcountry Tourer
  • Primary Travel Mode: Ski
  • Location Setting: Backcountry

Number

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

Avalanche

  • Type: SS
  • Trigger: AS - Skier
  • Trigger (subcode): u - An unintentional release
  • Size - Relative to Path: R3
  • Size - Destructive Force: D2
  • Sliding Surface: G - At Ground/Ice/Firm

Site

  • Slope Aspect: NE
  • Site Elevation: 10800 ft
  • Slope Angle: --
  • Slope Characteristic: Planar Slope

Avalanche Comments

The avalanche was most likely triggered from the toe, or bottom, of the avalanche path.

Weather Summary

Saturday's storm dropped 10 to 15 inches of dense snow across the zone, with the southern side of the North San Juan zone picking up the higher amounts. The nearby 13,065 foot Kendall Mountain CAIC/CDOT weather station showed a trend of south to southeast winds at 10 to 20 mph with gusts into the 30's for the 24 hours prior to the avalanche. On Sunday the 27th temperatures had risen only 3°Ffrom a morning low of 17°F  to 20°F at the time of the avalanche.

At the time of the avalanche skies were broken to overcast with occasional snow flurries.

Snowpack Summary

No formal snow pit examinations were done after the avalanche due to the storm cycle and resultant increase in avalanche danger following the event.
Rider 1 and Rider 2 did several hasty pits on similar aspects near where the avalanche started just prior to the avalanche release. The first set of tests found generally unresponsive results with Compression tests where the snowpack was an estimated meter deep. Columns basically crumbled with hard hits from the shoulder.
The second set of tests were done when cracks opened in the snow along their track. Two hasty Compression tests failed at the ground during isolation. There was a Q1 shear at the old snow, new snow interface when the block tipped over. The new snow was still quite soft, easily just fist hard. The lower snowpack was facets and depth hoar.

Events Leading to the Avalanche

On Sunday January 27, a group of four riders planned a tour into Swansea Gulch on Kendall Mountain east of Silverton. The four riders started at the Lackawanna Trailhead at 9,400 feet at the base of 13,066 foot Kendall Mountain, just east of Silverton at about noon. The group used two snowmobiles to access an elevation of about 10,600 feet in Swansea Gulch on the northern side of Kendall Mountain. The group parked the two sleds and began to climb south and east on skis and splitboards. At times Rider 1 and Rider 2 would set two separate up tracks. Along their tracks they did a few hasty pits on glacial moraine features with similar aspects to the overall northeast facing Swansea Gulch. Both Rider 1 and Rider 2 felt the snowpack was trending less stable as they continued their ascent, especially in areas that had a more shallow overall snowpack. Both Riders 1 and 2 felt that by staying in terrain with denser timber and a deeper overall snowpack they would have a better chance of avoiding an avalanche. Rider 1 and 2 called Rider 3 and 4 to come up and join them at a bench in Swansea Gulch above a local feature called "The Rabbit Ears". From this bench the group noted a fairly large fresh soft slab that had run out of another terrain feature called the "Coyote Tooth". This path is on a northeast aspect, several hundred vertical feet above the group. All four riders discussed the avalanche and their location on the mountain. At this point the group decided to traverse into the denser timber on the climbers right, or west, side of the gulch.  Rider 1 chose to go first and traversed west towards the timber. Just as Rider 1 was getting into the less dense timber at the edge of the forest they collapsed through the upper snowpack and into the deeper layers of depth hoar. As Rider 1 struggled to get their skis out of the deep snow Riders 2 through 4 began to yell "Avalanche" and Rider 1 looked uphill and saw the avalanche running downhill out of the sparse timber on the hill side above and to their left.  Rider 1 struggled to kick their skis out the hole but they were quickly bull-dozed over by the moving avalanche.

Accident Summary

When Rider 1 was hit by the heavy and dense debris they knew immediately that they were going for a ride. At that moment Rider 1 pulled the cord on their airbag and fought to spin around and get their head uphill.  Despite fighting as hard as possible Rider 1 was unable to get their head uphill and was swept a short distance down slope.  During the avalanche Rider 1 felt trapped and immersed in wet concrete and powerless to do anything to change their position.
Rider 1 came to a stop about 50 vertical feet down slope from where they were originally caught.



Rescue Summary

When the avalanche stopped Rider 1 was buried an estimated 12 to 18 inches deep at the head, head downhill, on their side. Rider 1's feet were upslope, about 3 feet deep (Neither ski had released in the avalanche) at about a 45 degree angle to the slope. Rider 2 estimated Rider 1's deployed airbag was about a foot to a foot and a half under the snow surface. Fortunately Rider 1, at the last second, was able to push a hand to the surface. Rider 1 remembers vigorously waving this hand to try to open an air channel, but their hand was not visible to the rest of the group at that time.

As soon as the avalanche began to run, Rider's 2, 3, and 4 changed  beacons from transmit to receive. Rider 2 looked for any sign of hang fire, and seeing none, began a primary beacon search. Within seconds Rider 2 had a signal and as the signal gained strength Rider 2 saw Rider 1's hand waving at the surface of the debris. Rider 2 went straight to Rider 1's hand and started digging with gloved hands. It only took a few more seconds to get to Rider 1's face. As Rider 2 began to dig down Rider's 3 and 4 arrived and started to dig with shovels. Rider 1 was breathing and conscious when uncovered.
Rider 2 estimated it took only 2 to 3 minutes from the time of the avalanche to when they uncovered Rider 1's airway.  After about 15 minutes the group descended back to their parked sleds under their own power. There were no reported injuries from the avalanche.


Comments

All riders had their climbing skins on. They were on a slight descent to avoid avalanche terrain above in order to gain denser forest. The group was spread out when Rider 1 collapsed through the old snowpack. 

It is most likely that Rider 1 triggered the avalanche when they broke through to the ground in old faceted snow.

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