AVALANCHE

Alberta, Rocky Mountains, Mount Thompson

On Sunday, February 22, 1981, a party of three set out to climb Mount Thompson from the Peyto Glacier, using the Peter Whyte Hut as a base. One party member left ahead of the other two and crossed in a northeasterly direction onto the northwest ridge of Mount Thompson. He reached the rocks, climbed through broken cliffs onto the ridge and then to the summit where he was to meet the others. The other two travelled east from the hut into a large steep bowl, intending to ascend snow slopes to a broken cliff and then proceed to the ridge to join their partner.

The lone party member waited at the rendezvous site for some time and then began to descend the route to be taken by the other two. Approximately halfway down he was caught in a slab avalanche and was carried approximately 150 vertical meters. He was buried and resurfaced a couple of times on the way down but he was able to dig himself out when the slide stopped. He observed that since morning two avalanches had come down into the bowl. Returning to the hut, he waited until approximately 2:00 p.m.; he then skied out to the Banff-Jasper Highway for help, arriving at Lake Louise at approximately 9:30 p.m.

The following morning a warden rescue team was flown to the site at first light. A search dog located both victims in less than five minutes. They were found roped together, lying on their backs under one to one and a half meters of snow, with their heads downhill. They were at the very toe of the slide, within two meters of undisturbed snow. The avalanche was approximately 200 meters wide, 200 meters long, and 30-60 cm deep on a slope of 30-35°. (Source: C. Israelson, Banff National Park)

Analysis

The bowl is very steep, a huge snow bowl broken only by a few rocks and small cliff bands. In the Canadian Rockies, it is almost never safe to enter this type of terrain in the winter.

This was the third fatal avalanche accident to occur in the area that weekend. The snow- pack was critically unstable and the National Park Service (NPS) was advertising a high- to-extreme avalanche hazard. On their approach to the hut, the party had observed the aftermath of several recent avalanches.

For some reason, the two men were roped together, although they were not on or near any terrain requiring a rope for safety. The rope was found to be stretched very tightly between the two and probably hampered their efforts to fight to the surface as the avalanche moved down the slope. Without the rope dragging them down, they might have been able to avoid total burial. (Source: C. Israelson, Banff National Park)