Analysis of the Durrand Glacier Avalanche Accident

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Durrand Avalanche Report page 21 3. At the accident scene, there were initially only seven survivors available to carry out the rescue. There is no record of whether all of the rescuers had proper dedicated avalanches probes and shovels, and whether they were able to efficiently use their avalanche transceivers to locate the buried victims. Some reports suggest that some of the rescuers only had ski poles to use as probes, and small, less effective plastic shovels. There is also some indication that the rescuers coming down the couloir initially walked over the first two fully buried victims without picking up a transceiver signal, which suggests that they may not have been effectively using their avalanche transceivers at this time. One client claims that the group received only an hour and a half of transceiver and rescue practice when they arrived at the chalet. It is also not known what brand of transceivers were being used, and whether they were all in good working order. 4. Of the 13 skiers who were caught in the slide, six survived and seven died. There is some inconsistency about how many people were totally buried; most likely eight were fully buried, and five were partially buried. Only one of the eight skiers who were totally buried survived; he was found 280 centimetres down after 30 minutes. According to Larry Stanier’s report to the Coroner, those who died were buried from 130 to 280 cm deep. T. Textbook advice on how to travel safely in avalanche terrain 1. Numerous avalanche books describe weather, snowpack and terrain features likely to increase avalanche risk, and also how to travel with relative safety in avalanche country. The most common edicts noted are as follows: (a) Before heading out into the backcountry, check and heed the advice in Public Avalanche Bulletins, and from other information sources. (b) Be aware of how smooth the underlying ground is on a potential avalanche slope (assess ground roughness), and what depth of snow may create an avalanche hazard. (c) Track the history of the winter snowpack so that potentially unstable layers, or conditions that might cause unusual avalanche activity, can be recognized and managed. (d) Be extra cautious about avalanche hazard immediately after a storm, especially if more than 25 cm of snow has fallen in a short period of time, strong winds have been present, temperatures are rising, or other unusual weather or snowpack conditions have occurred. (e) In winter, be extra cautious of lingering hazard during cold conditions, or on colder, shaded slopes where processes that create unstable snow crystals, or retard the stabilization of new snow, may be present. (f) Be aware of exposures, especially in spring and summer, where the effects caused by increasing temperatures or radiation may destabilize the snow and increase avalanche hazard. (g) Be aware of wind loaded lee slope areas where winds have caused larger amounts of denser snow to accumulate. Lee slope build-up may occur below ridges, or any place on a slope where the presence of undulating terrain, such as a couloir, causes snow to accumulate. Copyright: no part of this report may be reproduced without the written permission of the author.
Durrand Avalanche Report page 22 (h) Be extra cautious in areas where stresses in the snow may be greater, such as steep slopes (especially those greater than about 30°), convex slopes, and wind-loaded slopes. (i) Be sure to consider not only whether a slope may slide, but also what would happen if it does. Gullies, large slopes, slopes above cliffs, crevasses, flat valley bottoms, narrow valleys, bodies of water, and other terrain traps, must be treated with extra caution. (j) Before deciding on whether or not to cross a potential avalanche slope, consider the remoteness of the location, weather, time of day, strength of the party, and similar factors that may influence how effective an avalanche rescue would be. Consider also whether safer alternative routes are available, and whether the party should turn around, rather than risk being avalanched. (k) If a slope that may avalanche must be crossed, complete additional snow stability assessments, check safety equipment, do up clothing, ensure that a minimum number of people at a time are exposed to the hazard, take advantage of islands of relative safety, move as quickly as it is safely possible to do so, and be prepared to carry out an avalanche rescue. (l) When touring up a valley, try and stay outside of the 25° avalanche shadow zone below a potential avalanche slope. (m) Complete regular transceiver practices, including ones with multiple burials. Ensure that a touring group knows how to carry out an efficient avalanche rescue if a slide occurs. U. Police statements on the accident 1. After the accident, on January 21, 2003, the Royal Canadian Mounted Police in Revelstoke held a press conference at which they made the following statements: (a) The avalanche had occurred at approximately 10 am (another press release stated that the avalanche had occurred shortly before 11 am). (b) The accident site was approximately 55 km northeast of Revelstoke. Measurements with a global positioning system (GPS) indicate the accident site is about 35 km north northeast of Revelstoke. The Coroner’s Inquiry report describes it as being 25 km north of Revelstoke. (c) The avalanche was 300 feet (91 m) long, and 75 to 100 feet (23 to 30 m) wide. Information in Larry Stanier’s report to the Coroner indicates that the avalanche was a total of 360 metres long, 65 metres wide at the crown, and 185 metres wide in the deposition area. (d) That “there is nothing in the initial investigation at this time to lead investigators to believe that this is nothing more than a tragic accident.” This statement was made while investigators were still in the field gathering data, and before any analysis of the accident had even been started. Copyright: no part of this report may be reproduced without the written permission of the author.
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Analysis of the Durrand Glacier Avalanche Accident

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