07-08 Accidents

View of both slide from road.

Topo map of slide area

Skiers descended skiers left of the slide path with no incident. At approximatly 9,800' the avalanche was triggered, propagated above the skiers to the steeper part of the start zone, 40*, and released. Subject 1 was swept approx. 400 vertical feet and buried with head and 1 hand exposed. Subject 2 was to the side of the slide and grabbed onto a tree and was partially buried. Each skier lost 1 ski and poles. A dog was not recovered. The initial ski tracks were left intact. A sympathectic release to the skiers right was much larger and entrained more snow than the initial slide. Subjects had skied similar neighboring terrain the previous day without incident, as well as previously that day. They had checked the avalanche report and discussed the hazard. Their thought process led them to believe they were away from the most loaded portion of the start zone, and protected by the treed ridge above them. The avalanche was triggered from below, propagating above the skiers. The initial slide was 50m wide running 1,400 vertical feet with an average crown depth of 2 feet and an alpha angle of 35*. The secondary release was much larger, approx 200m wide running 1,400 vertical feet with an avarage crown depth of 3 feet with some areas close to 5 feet and an alpha angle of 35* with the max angle in the start zone 42*.
Each subject was able to free themselves and make out to the road and their car on their own. 911 was called by a witness across the valley but search and rescue was not deployed.

Fracture line profile

Looking down the skier triggered slide

Spot of 2nd partially buried skier and sympathetic slide

Looking up at skier triggered slide

Crown of sympathetic slide. Slope angle 42 degrees.

Pit profile of crown and failure layers

Looking up path