Avalanche Accidents in Canada. II. a Selection of Case Histories Of
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ANALYZED . ' r.. --. .- -. NATIONAL RESEARCH COUNCIL OF CANADA DIVISION OF BUILDING RESEARCH AVALANCHE ACCIDENTS IN CANADA 11. A SELECTION OF CASE HISTORIES OF ACCIDENTS 1943 TO 1978 b Y C.J. Stethem and P.A. Schaerer DBR Paper No. 926 of the Division of Building Research OTTAWA, July 1980 AVALANCHE ACCIDENTS IN CANADA 11. A SELECTION OF CASE HISTORIES OF ACCIDENTS 1943 TO 1978 by C.J. Stethem and P.A. Schaerer ABSTRACT Case histories are presented of avalanche accidents in Canada that resulted in death or injury. A first volume describing accidents between 1955 and 1976 was published earlier (NRCC 17292). The present publication contains cases from the winters 1976 to 1978 and a few selected ones from earlier years. They contain a description of the weather, snow conditions, circumstances leading to the accident, the event, and the rescue operation. ACCIDENTS CAUS~SPAR LES AVALANCHES AU CANADA 11. CHOIX DE CAS DOCUMENT~SD'ACCIDENTS DE 1943 1978 par C.J. Stethem and P.A. Schaerer Des cas dlaccidents caus6s par des avalanches au Canada ayant provoqug la mort ou des blessures sont pr6sentGs. Un premier volume dgcrit les accidents qui se sont produits entre 1955 et 1976 a 6t6 publigs plus t6t (NRCC 17292). Cette publication contient les cas des hivers de 1976 5 1978 et certains autres cas choisis dans le rgpgrtoire des ann6es pr6cGdentes. Les cas documenti% contiennent une description de la tempgrature, des conditions de la neige, des circonstances qui ont conduit 2 l'accident, l'accident comme tel, et 110p6ration de sauvetage. FOREWORD The objective of the avalanche research program of the Division of Building Resea~chof the National Research Council is to develop and make available information about snow avalanches and protection from them. In partial fulfillment of this objective, case histories of accidents were collected that either resulted in death, injury, or property damage or have educational value. A first volume describing 40 accidents between 1955 and 1976 was published earlier (NRCC 17292). The present publication contains the accident cases of the two winters between 1976 and 1978 and some additional ones from earlier years. The case histories presented in this report were collected by Mr. Chris Stethem, working on Contract OSS77-08171 with the National Research Council of Canada. Mr. Stethem obtained the information from published reports, from files of agencies and through interviews with persons who were either eyewitnesses to the accident or involved in the rescue operation. The reader will notice an increase in the amount of information concerning individual accidents towards the end of this report. The most recent cases are well documented with weather, snowpack and avalanche observations. This is a reflection of a growth in interest and knowledge of personnel working in avalanche areas, which in some part, is the result of education in which the National Research Council played an important role by developing avalanche course programs, assisting in instruction and through publications such as this one. The compilation of accident case histories will continue, and publication of a further volume containing the numerous accidents and destructive avalanches of February 1979 is anticipated. Furthermore it is planned to collect statistics about the numerous encounters that have not resulted in death, injury, or serious property damage. The assistance of individuals and agencies who make available information is gratefully acknowledged, and it is expected that the same co-operation will continue. Ottawa C.B. Crawford July 1980 Director, DBR/NRC ACKNOWLEDGEMENT The National Research Council wishes to express its thanks to the following agencies, organizations, and individuals who have contributed information. Apex Alpine Recreations Ltd. Atmospheric Environment Service Canada British Columbia Ministry of Transportation and Highways British Columbia Ministry of Lands, Parks and Housing British Columbia Ministry of the Attorney-General Canadian Mountain Holidays Canadian National Railways Garibaldi Lifts Limited Ocean Falls Corporation Parks Canada Suret6 de Quebec Workers Compensation Board of British Columbia B. Geisler W. Jenkins W. Kleinschrot R. Neville C. Sadleir LIST OF THE ACCIDENTS 11 February Kwinitsa Workmen killed, Construction camp destroyed 23 February Fraser Canyon Person on road killed 14 January Fraser Canyon Workman killed 27 March Seymour Inlet Workman killed 23 February Woodbury Creek Person on road killed 24 March McGillivray Pass Skiers killed 7 April Torbit Mine Workman killed 19 July Mt. Garibaldi Mountain climber killed 21 January Silver Star Skier killed 13 January Ocean Falls Persons in buildings killed, buildings destroyed 11 August Mt. St. Elias Mountain climbers killed 14 March Nine Mile Mountain Snowmobile operator killed 13 February Westcastle Workman injured 11 June Mt. Fisher Mountain climbers injured 11 December Sunshine Village Skier buried 12 December Chancellor Peak Mountain climbers killed 28 December Tadoussac Snowmobile operator killed 15 February Parker Ridge Skier killed 16 March Diana Lake Skier killed 17 March Bugaboo Skiers killed 19 March Bow Peak Mountain climber killed 21 March Apex Mountain Skier killed 27 March Quartz Ridge Skier killed 30 March Lake Louise Skier killed 7 September Mt. Athabasca Mountain climbers injured 9 October President's Col Mountain climber killed 8 March Whistler Mountain Skiers buried PREFACE The list of accidents described in this publication is a reflection of the change in activities in the mountains of Western Canada and the shift in the type of involvements with avalanches. In the years before 1960 avalanche accidents occurred mainly on roads and in work areas such as construction, mining and logging, but when recreation in the mountains became more popular the number of acctdents involving skiers and mountain climbers increased. On the average seven people per year have died in avalanches in Canada between 1970 and 1978, the period when accurate records were maintained. With 13 deaths the winter of 1976-1977 was above average, and all 13 persons were involved in recreational activities. Three important conclusions can be drawn from features common to several cases. 1. The time for survival of persons completely encased in the snow is very short. This means that live rescue depends on the quick action of the accident witnesses who must immediately search likely areas of burial. Obviously rescue transceivers and probes assist greatly in locating buried victims, and shovels carried by the rescuers are essential for a quick recovery. 2. Several persons on roads and on skis have died when a second avalanche ran after the first one. For this reason danger from later avalanches and proper safety measures must be considered in rescue and snow removal operations. 3. Some skiers were caught in avalanches on slopes that had been treated with artillery fire a short time before. When a deep slab instability exists such slopes may be considered safe only when avalanches were actually observed and the unstable snow removed. KWINITSA, SKEENA RIVER VALLEY, B.C. 11 FEBRUARY 1943 Three men killed, eleven injured, several buildings destroyed WEATHER Observations at Terrace Airport, 60 m ASL Temperature Precipitation Oc Date Max Min mm 7 February 4.5 3.0 45 8 February 3.5 0.5 30 9 February 4.0 -0.5 5.5 10 February 0.5 -6.5 11 February 0 -3.5 2.5 Experience has shown that warm moisture laden fronts usually arrive earlier and deposit more snow at the accident site than at Terrace. On 12 and 13 February a total of 51 mm of precipitation was recorded at Terrace Airport. SITUATION The accident site was at McLean Point on the shore of the Skeena River 85 km west of Terrace. A construction camp to house workmen building the highway from Terrace to Prince Rupert was located beside the railway tracks in the runout zone of a large avalanche gully. In the early winter of 1942-43 officials of the Canadian National Railway visited the camp and warned the superintendent of the avalanche danger. In January 1943 an avalanche descended the gully and blocked about 30 m of the railway track but did not reach the camp. A railroad engineer again visited the camp and told of a snowshed that had been destroyed at the same site about 10 years earlier. By early February the avalanche hazard had become the central topic of discussion among the 200 men working in the camp. During the second week of February a storm raged in the area. Most of the precipitation fell as rain at the lower elevations, but on the night of 10 February snow was deposited at the camp. ACCIDENT SUMMARY At about 0730 h on 11 February most of the men had finished break- fast and were preparing to leave for work, when suddenly a rumbling was heard. An avalanche swept down the gully and struck the camp carrying away two small bunkhouses and the first aid shack. Several men were caught. One of them who had been standing by a 14-ton locomotive was crushed by the moving snow and debris, and another one close-by was swept away and buried. Those who escaped the avalanche aided the injured, moving them to the remaining bunkhouses and then, because other avalanches seemed imminent, to the patrolmen's shack at Telegraph Point, 2 km west. Other survivors remained behind and searched for those still missing. As the injured men were being moved a second slide struck, and destroyed the two remaining bunkhouses. Several men were partially buried and some were carried into the river. Only the office at the east end of the camp and the commissary at the west end remained standing. About twenty minutes later, when the remaining men were moving to safety, a third avalanche struck destroying the office. RESCUE A westbound passenger train arrived at the site about one and one half hours after the first avalanche.