- Location: Schuykill Ridge, Birthday Bowl. Near Crested Butte
- State: Colorado
- Date: 2014/12/18
- Summary Description: 1 skier caught and injured
- Primary Activity: Backcountry Tourer
- Primary Travel Mode: Ski
- Location Setting: Backcountry
- Caught: 1
- Partially Buried, Non-Critical: 0
- Partially Buried, Critical: 0
- Fully Buried: 0
- Injured: 1
- Killed: 0
- Type: SS
- Trigger: AS - Skier
- Trigger (subcode): u - An unintentional release
- Size - Relative to Path: R1
- Size - Destructive Force: D2
- Sliding Surface: O - Within Old Snow
- Slope Aspect: NE
- Site Elevation: 11300 ft
- Slope Angle: 41 °
- Slope Characteristic: Convex Slope,Planar Slope
The avalanche was a soft slab, unintentionally triggered by a skier (SS-ASu-R1D2-O). It was small relative to what the path could produce, and destructive enough to bury and kill a person. It broke in old snow 1 to 2 feet deep, was about 25 feet wide, and ran approximately 550 vertical feet. It started on an north-northeast aspect near treeline, on steep treed slope right below ridgeline, and then ran into a more open and confined gully.
The Crested Butte area received snow in mid October and early November. Most of this snow melted, except for high-elevation north-facing terrain. The first significant snow event to bury the surviving early season snow arrived on Nov. 12th, and from Nov. 12th-15th dropped between 15 to 32 inches of snow and nearly 3” SWE (snow water equivalent). A week-long period of mild days and cold nights followed this storm. A multiple day storm event bean Nov. 22ndm tand dropped 15-20” snow and almost 2” SWE. After Nov. 22nd the Elk Mountains saw very little precipitation for three weeks. On December 13th, a winter storm dropped around 18" of new snow to the Schuykill area over a few day period. The weather was dry, cool, and mostly calm during the 2 days prior to the accident.
The snowpack was weak and consisted of three prominent weak layer interfaces corresponding to the main storm events. Periods of dry weather in between storm events led to the development of crusts on low elevation and sunny slopes, near surface facets on shady slopes, and depth hoar at the bottom snowpack in most locations. On December 13th, a winter storm dropped around 18" of new snow that fell on extremely weak 2mm near surface facets and various degrees of melt freeze crust on all but the most sheltered, north facing terrain. This December 13th interface would turn out to be the culprit of a small natural avalanche cycle in the area, as well as the bed surface in this December 18th Schuykill Ridge avalanche incident.
Events Leading to the Avalanche
A party of 2 (Skier 1 and Skier 2) very experienced backcountry skiers set out for a short tour to Schuykill Ridge. This was familiar terrain that they had skied numerous times before. They had been reading the avalanche forecasts in the days prior to the accident and knew the avalanche problem was weak facets underlying a slab of varying hardness and thickness. The pair stuck to the standard skin track ascending through moderately dense trees, poling and probing the snow a few times as they ascended. Once at the top of the ridge, the pair transitioned to downhill ski mode.
Skier 1 dropped into the steep north-facing slope around 1:45pm, planning on taking two hard turns before committing to fall-line skiing. On the first right hand turn, the slope fractured several feet above Skier 1, and picked up speed quickly. Skier 2 yelled, and Skier 1 almost skied out of the slide before getting pushed over and losing control. Shortly after becoming caught, Skier 1 was carried into a tree, breaking a leg on impact. Skier 2 watched Skier 1 for a few seconds before losing visual contact.
About 1/3 of the way down the slope, Skier 1 self-arrested with the uninjured leg, digging it into the bed surface near a large stump, and allowing the remaining moving snow to wash down-slope. After stopping, Skier 1 yelled back up Skier 2 that he was okay, but had a broken leg. Afraid of sending more snow down on Skier 1, Skier 2 gingerly made their way down on the faceted and slightly crusty bed surface mixed with rocks, dirt and rocks. Despite the tricky descent, Skier 2 reached Skier 1 in under 5 minutes.
Once on scene, Skier 2 performed a quick size up of the scene, informal head to toe exam, and ruled out any other serious injuries. Skier 2 placed a cell phone call to 911 at 2:00pm, and handed the phone to Skier 1, while they retrieved a ski and attempted to splint the injured leg. Once the 911 call was placed, the pair began to move downhill, with Skier 1 sliding on their bottom. Farther down-slope, Skier 1 used a ski to aid sliding in the deep faceted snow. The pair descended an estimated 1300 vertical feet to the bench where the medical helicopter was able to land at 4:02pm. The helicopter departed around 4:19 pm and Skier 1 was flown to definitive medical care.
This accident illustrates that a small avalanche can result in serious consequences. The skiers involved in the accident did a tremendous job descending and extricating themselves to a landing zone suitable for the helicopter. The pilots also did a difficult job flying in and landing in less than ideal conditions. Had the helicopter not been able to land, extricating Skier 1 would have been much more involved and taken considerably longer.
Figure 10: Fracture line profile. Schuykill Ridge 12.19.14