Avalanche Account

AVALANCHE!

by Carol Swanton

On the 10th of February I was participating in the field portion of the National Avalanche School's program at Galena Summit, just north of Sun Valley, Idaho. We were a group of 8 back country skiers led by Doug Abromeit, Ketchum's National Forest Service avalanche forecaster.

It was a phenomenally gorgeous, cloudless sunny day (by Northwest standards!) following the week of bone chilling cold temperatures and then a few days of precipitation. Avalanche hazard was rated pretty high. We set out from about the 8900 foot level just south of Galena Summit on Titus Ridge, where the Forest Service maintains a weather station. The mission was to enhance our avalanche analysis skills - we dug snow pits, did shovel shear tests, performed Rutschblock tests and just plain looked at and felt the snow to determine the snowpack layers.

That day and the prior, Friday, we found a pretty recurrent weak layer at about 15 inches. We stopped at a couple of places to do some ski cutting and slope testing on belay, choosing what appeared to be benign slopes - relatively short and terminating in a cluster of trees. One of these spots was at about 9700' just above Titus Lake on a slope with a north east aspect at around 2 pm.

I had watched most of the other members of the group demonstrate and practice the technique and had belayed someone else down a slope. Now it was my turn. We had just watched Jan Thompson, our very own Cascade Nordic, go down the same slope and report that all was well. I put on the climbing harness, adjusted the figure 8 knot and started down the slope. To my right was a small cross loaded gully and about 20' down the about 30 degree slope, it became convex and sloped off more steeply. I reached that point uneventfully and glanced back up at the other members of the group to announce I would take another step down and then be on my way up. It was getting a bit boring!

Most of the group had dispersed to another location to practice burying 'dead men' for use as belay anchors, so I saw maybe 3 or 4 folks above me. I stepped down with my left leg and immediately sunk down another 6" or so while hearing at the same time an ominous "Woomph". I looked up the hill to my belayer, who had assumed a very compact and efficient position. He was surrounded by the rest of the group who, apparently, had felt the ground drop even at their somewhat farther distance. All were clinging to trees and had eyes like saucers staring down toward me. I watched a fracture begin a few feet below and to the right of me on the little gully. I watched as the fracture propagated across to my left, up the hill at an angle and across the top of the bowl next to me for about 500'. The whole hill let loose as a brittle slab with about a 5' crown face and cascaded down the slope leaving a huge deposition sitting in front of the lake, which, according to my topo map, was at about 8900'. My comments on the matter at the time are all pretty much unprintable.

We spent a sobering rest of the afternoon analyzing the bed surface and crown face. Our avalanche had slid on a deep layer of depth hoar put down during the cold dry period immediately before Christmas. This was a layer I seem to recall seeing in our pit as being very small. Doug has promised to send each member of the group his snow pit analysis from this avalanche. We also watched some skiers in the distance huddle together at the top of the same ridge until they finally sent out one skier to the slope on which they had been skiing to perform some snowpack tests. We elected to return to our automobiles along the same ridge we had come in on. I think I probably got a vivid first hand lesson on the effects of stored elastic energy in a snowpack and the group dynamics of route selection.

On a sadder note, there was another avalanche that same day on Paradise Peak in the Smoky Mountains, several miles south west of Galena Summit where a guide for Sun Valley Heli-Ski and member of the Sun Valley Ski patrol, James Ray Otteson, died. This, despite the fact that he was recovered within 15 minutes under about 4' of snow, thanks to his rescue beacon. He was at about 9200' on a west facing slope.

Many of us at Hyak think of avalanches as something that could probably never happen to us. Statistically, Washington is second in terms of avalanche fatalities, behind Colorado. With our increasing back country responsibilities, avalanche training is something our patrol needs to give some serious thought to.

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