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Conseil national
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AVALANCHE ACCIDENTS IN CANADA
I. A SELECTION OF CASE HISTORIES
OF ACCIDENTS, 1955 TO 1976
RNRr
by C.J. Stethem and P.A. Schaerer
$,.
DBR Paper No. 834
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Division of Building Research
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Price $1.50
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NATIONAL RESEARCH COUNCIL OF CANADA
D I V I S I O N OF BUILDING RESEARCH
AVALANCHE ACCIDENTS I N CANADA
I.
A SELECTION OF CASE H I S T O R I E S OF ACCIDENTS 1955 TO 1976
C . J . S t e t h e m and
P . A . Schaerer
DBR P a p e r N o . 834
of the
D i v i s i o n of B u i l d i n g R e s e a r c h
Ottawa
F e b r u a r y 19 79
AVALANCHE ACCIDENTS I N CANADA
I. A SELECTION OF CASE HISTORIES OF ACCIDENTS 1955 TO 1976
by
C . J . Stethem and P.A.
Schaerer
ABSTRACT
Case h i s t o r i e s are p r e s e n t e d of a v a l a n c h e a c c i d e n t s i n Canada t h a t
r e s u l t e d i n d e a t h , i n j u r y o r s e r i o u s d e s t r u c t i o n of p r o p e r t y i n t h e y e a r s
between 1955 and 1976. They c o n t a i n a d e s c r i p t i o n of t h e c i r c u m s t a n c e s
l e a d i n g t o t h e a c c i d e n t , t h e e v e n t , and t h e r e s c u e o p e r a t i o n , b u t t h e y
do n o t i n c l u d e a l l a c c i d e n t s owing t o i n s u f f i c i e n t i n f o r m a t i o n . Whenever
p o s s i b l e , weather observations a t t h e c l o s e s t c l i m a t o l o g i c a l s t a t i o n a r e
g i v e n f o r t h e day of each a c c i d e n t and t h o s e p r e c e d i n g i t . Compilation
of c a s e h i s t o r i e s w i l l c o n t i n u e and p u b l i c a t i o n of a second volume i s
anticipated.
ACCIDENTS
CAUSES
I. CHOIX DE CAS
par C . J .
PAR DES AVALANCHES AU CANADA
DOCUMENT^^
Stethem e t P.A.
D'ACCIDENTS DE 1955
1976
Schaerer
On p r 6 s e n t e d e s c a s document6s d l a c c i d e n t s c a u s g s p a r d e s a v a l a n c h e s
a u Canada q u i p r o v o q u s r e n t l a mort, d e s b l e s s u r e s o u d e g r a v e s dommages
On d g c r i t l e s
d e s b i e n s d e s pecsonnes, d e s annges 1955 2 1976.
c i r c o n s t a n c e s q u i mensrent 2 l ' a c c i d e n t comrne t e l , e t 1 1 0 p 6 r a t i o n de
s a u v e t a g e , m a i s t o u t l e s c a s n e s o n t p a s r a p p o r t 6 s 2 c a u s e d ' u n manque
d' i n f o r m a t i o n . L o r s q u l i l e s t p o s s i b l e , d e s o b s e r v a t i o n s s u r l e temps 2
l a S t a t i o n mi5ti5orologique l a p l u s proche s o n t donnges pour l e j o u r de
chaque a c c i d e n t e t pour l e s j o u r s q u i p r g c g d s r e n t . La c o m p i l a t i o n de c e s
c a s documentgs s e r a p o u r s u i v i e e t on p r g v o i t p u b l i e r un deuxisme volume.
FOREWORD
Knowledge i s g a i n e d from o u r m i s t a k e s and t h e m i s t a k e s o f o t h e r s .
I t was w i t h t h i s i n mind t h a t t h e D i v i s i o n o f B u i l d i n g Research o f t h e
National Research Council o f Canada a r r a n g e d f o r a c o l l e c t i o n o f c a s e
h i s t o r i e s of avalanche a c c i d e n t s r e s u l t i n g i n death, i n j u r y , o r s e r i o u s
destruction of property.
The a c c i d e n t h i s t o r i e s c o n t a i n e d i n t h i s r e p o r t were c o l l e c t e d by
M r . C h r i s Stethem, working on C o n t r a c t No. 032-502 w i t h t h e N a t i o n a l
Research C o u n c i l . M r . Stetham o b t a i n e d t h e i n f o r m a t i o n from p u b l i s h e d
r e p o r t s , from f i l e s o f a g e n c i e s , and t h r o u g h i n t e r v i e w s w i t h p e o p l e who
were e i t h e r e y e w i t n e s s e s o f t h e a c c i d e n t o r involved w i t h t h e r e s c u e
o p e r a t i o n . A s many t e c h n i c a l d e t a i l s a s p o s s i b l e a r e i n c l u d e d , b u t i n
some c a s e s i m p o r t a n t i n f o r m a t i o n , f o r example, t h e d e p t h o f b u r i a l o f a
v i c t i m , t h e number of p e o p l e i n v o l v e d i n t h e s e a r c h , o r t h e snow
c o n d i t i o n s r e s p o n s i b l e f o r t h e a v a l a n c h e , c o u l d n o t b e found.
The c o m p i l a t i o n o f c a s e h i s t o r i e s w i l l c o n t i n u e and t h e p u b l i c a t i o n
o f a second volume i s a n t i c i p a t e d , w i t h a d d i t i o n a l c a s e s from e a r l i e r
y e a r s , t o g e t h e r w i t h t h e a v a l a n c h e a c c i d e n t s s i n c e 1976. The a s s i s t a n c e
o f N a t i o n a l Parks p e r s o n n e l a n d o t h e r s i s g r a t e f u l l y acknowledged.
Ottawa
February 1979
C .B . Crawford
D i r e c t o r , DBR/NRC
ACKNOWLEDGEMENT
The National Research Council wishes t o e x p r e s s i t s thanks t o t h e
f o l lowing agencies and o r g a n i z a t i o n s t h a t have c o n t r i b u t e d i n f o r m a t i o n .
Atmospheric Environment S e r v i c e Canada
B r i t i s h Columbia M i n i s t r y o f Highways
and Pub 1i c Works (Highways)
B r i t i s h Columbia M i n i s t r y of Mines
Canadian Mountain Holidays
Canadian S k i P a t r o l System
Garibaldi L i f t s Ltd.
Metropol i t a n Toronto Pol i c e
Parks Canada
Red Mountain S k i Club
Royal Canadian Mounted P o l i c e
Whitewater S k i S o c i e t y
LIST OF THE ACCIDENTS
11 J u l y
1955
Mount Temple
Mountain c l i m b e r s k i l l e d
11 March
1956
Marmot Basin
Skier killed
17 March
1957
Richardson Ridge
Skier k i l led
23 November 1958
Bow summit
Skiers k i l l e d
30 January
1960
Toby Creek
Person on a road b u r i e d
23 May
1960
Mount Athabasca
Mountain climbers i n j u r e d
20 June
1960
Mount Athabasca
Mountain c l i m b e r i n j u r e d
30 December 1962
Mount Whaleback
Skier killed
28 A p r i l
Temple S k i Area
Skier buried
18 February 1965
Granduc Mine
Workmen k i l l e d , mine camp
destroyed
28 February 1965
Mount Norquay
Skier killed
28 December 1965
Kootenay Pass
Person on road k i l l e d
1963
8 January
1966
Rogers Pass
Workmen k i l l ed
30 January
1967
Mount Whi t e h o r n
Skier killed
16 March
1967
Koo tenay Pass
Person on road b u r i e d
Parker Ridge
Skier k i l l e d
9 December 1967
23 March
1969
Mount Hector
Skier killed
24 J a n u a r y
1970
Deception Pass
Skier buried
24 January
1970
Westcastle
Skier killed
1970
Deception Bay
Tank farm damaged
7 December 1970
Ruth-Vermont Mine
B u i l d i n g damaged
23 December 1971
G r a n i t e Mountain
Skier killed
24 December 1971
Flathead Valley
Persons on r o a d k i l l ed
Sc arborough
Tobogganers k i 11ed
Mount E d i t h Cave11
Mountain climbers k i l l e d
6 June
5 February 1972
19 February 1972
1 March
1972
Sunshine Area
Building destroyed, c a r s
buried
5 March
1972
Giant Mascot Mine
Persons on road k i l l e d
8 April
1972
W h i s t l e r Mountain
Skiers killed
23 A p r i l
1972
Apex Basin
Skier killed
W h i s t l e r Mountain
Skier buried
17 February 1973
9 December 1973
Bow Summit
Skier killed
16 January
1974
Ruth -Vernon t Mine
Buildings d e s t r o y e d
22 January
1974
North Route Cafe
Persons i n b u i l d i n g k i l l e d
17 February 1974
Mica Mountain
S k i e r k i 11ed
30 March
1974
Sunshine Area
Skier k i l l e d
16 March
1975
G r a n i t e Mountain
Skiers injured
16 March
1975
Red Mountain
Skier buried
14 J a n u a r y
1976
Cap S a n t 6
Tobogganer k i l l ed
16 January
1976
Kootenay Pass
Persons on road k i l l e d
23 March
1976
P a r a d i s e Basin
Skier killed
PREFACE
Avalanches u s u a l l y have n a t u r a l c a u s e s , b u t t h e y a r e sometinles
t r i g g e r e d b y t h e i r v i c t i m s and t h i s i s t r u e o f most s k i i n g
a v a l a n c h e a c c i d e n t s . The c a s e h i s t o r i e s p r e s e n t e d i n t h i s
p u b l i c a t i o n contain a d e s c r i p t i o n o f t h e circumstances leading t o
t h e a c c i d e n t , t h e e v e n t , and t h e r e s c u e o p e r a t i o n . They c o v e r t h e
y e a r s between 1955 and 1976, b u t do n o t i n c l u d e a l l t h e a v a l a n c h e
a c c i d e n t s t h a t have o c c u r r e d i n Canada d u r i n g t h a t p e r i o d owing t o
i n s u f f i c i e n t i n f o r m a t i o n . Numerous e n c o u n t e r s n o t r e c o r d e d h e r e
have o c c u r r e d e v e r y w i n t e r ; s k i e r s have been c a r r i e d down by
a v a l a n c h e s and escaped w i t h o u t i n j u r y , o r v e h i c l e s have been caught
on r o a d s , t h e i r o c c u p a n t s l e f t unharmed. Although t h e s e n e a r a c c i d e n t s would b e i n s t r u c t i v e , t h e y have been o m i t t e d b e c a u s e t h e y
were u s u a l l y n o t a d e q u a t e l y documented.
Weather o b s e r v a t i o n s a t t h e c l o s e s t c l i m a t o l o g i c a l s t a t i o n a r e
g i v e n f o r t h e day of t h e a c c i d e n t and t h o s e p r e c e d i n g i t . Snowfall
and t e m p e r a t u r e a t t h e s e s t a t i o n s a r e a n i n d i c a t i o n o f t h e
c o n d i t i o n s a t t h e a c c i d e n t s i t e s , a l t h o u g h owing t o d i s t a n c e and
d i f f e r e n c e s i n e l e v a t i o n t h e y may n o t b e e x a c t l y t h e same.
Almost o n e - h a l f o f t h e a c c i d e n t s d e s c r i b e d i n t h i s p u b l i c a t i o n
o c c u r r e d i n N a t i o n a l P a r k s . One r e a s o n f o r t h i s i s t h e obvious one
t h a t s k i e r s and mountain c l i m b e r s t e n d t o c o n c e n t r a t e t h e r e .
Another f a c t o r i s t h e d e t a i l e d r e c o r d s t h a t a r e m a i n t a i n e d b y
w e l l - t r a i n e d and equipped P a r k s p e r s o n n e l a s p a r t o f t h e i r e f f o r t
t o i n c r e a s e s a f e t y c o n s c i o u s n e s s i n a v a l a n c h e t e r r a i n . These were
made a v a i l a b l e f o r t h e p r e s e n t s t u d y .
MOUNT TEMPLE, LAKE LOUISE, ALBERTA
11 J U L Y 1955
Seven mountain c l i m b e r s k i l l e d , two i n j u r e d
WEATHER
Observations a t Lake Louise Townsite, 1530 m ASL
Temperature
O
Date
Max
7 July
14.5
8 July
15.5
9 July
21
10 J u l y
22
11 J u l y
24.5
Precipitation
c
Min
m
11 J u l y was a warm, sunny day i n t h e Lake Louise a r e a .
ACCIDENT SUMMARY
A group of 24 teenage youths from a w i l d e r n e s s camp i n
United S t a t e s had camped a t Moraine Lake, i n t e n d i n g t o hike
t h e a r e a . On 11 J u l y 18 of them s t a r t e d climbing t h e south
Temple from a p o i n t j u s t below S e n t i n e l Pass on t h e Moraine
s i d e . A l l were inexperienced i n rock climbing.
the eastern
and climb i n
f a c e of Mount
Lake Valley
Half way t o t h e mountain t h e two group l e a d e r s and f i v e o t h e r s
decided t h a t t h e climb was t o o d i f f i c u l t f o r them and t h a t they would n o t
c o n t i n u e . The e l e v e n o t h e r boys proceeded, roped a t 5 - f t (1.5 m) i n t e r v a l s
on a 9 mm m a n i l a rope. A t approximately t h e 2750 m l e v e l they found t h a t
t h e r o u t e was t o o dangerous and s t a r t e d t o r e t u r n , b u t i n c r o s s i n g a snow
s l o p e they were caught by an avalanche and swept down. The time was
approximately 1600 h.
RESCUE
The rope t o both t h e l e a d and t a i l men broke a s t h e p a r t y was swept
down, and t h e two managed t o s t a y on t h e s u r f a c e u n i n j u r e d . I n a s t a t e
of shock, t h e y walked t o Moraine Lake Chalet where t h e y r e p o r t e d t h e
a c c i d e n t a t approximately 1730 h .
The manager of t h e C h a l e t immediately n o t i f i e d t h e National Park
Warden S e r v i c e , and an advance p a r t y o f two wardens and a d o c t o r l e f t
Moraine Lake C h a l e t a t 1910 h, a r r i v i n g a t t h e a c c i d e n t s i t e a t 2130 h.
A follow-up p a r t y o f 20 men l e f t a t 2145 h.
The advance p a r t y found t h r e e boys dead a s soon a s they a r r i v e d and
a t 2145 h two boys a l i v e w i t h s e v e r e m u l t i p l e i n j u r i e s . The f i v e were
found w i t h i n a 30 m a r e a . The follow-up p a r t y a r r i v e d a t 0030 h and
proceeded t o evacuate t h e i n j u r e d . Two a d d i t i o n a l v i c t i m s were found
dead a t 0300 h, 60 m above t h e o t h e r s . A t t h a t time most o f t h e followup p a r t y was withdrawn because t h e danger o f f u r t h e r avalanches loomed
and many p a r t y members were inexperienced. The remaining s e a r c h e r s
continued t o probe, and t h e l a s t two v i c t i m s were l o c a t e d , dead, s h o r t l y
b e f o r e dawn, 12 J u l y . A l l b o d i e s were removed t o Banff and o p e r a t i o n s
were concluded a t 1330 h.
AVALANCHE
The avalanche s t a r t e d i n wet, l o o s e snow, was about 10 m wide and
was caused by r a d i a t i o n from t h e sun. The p a r t y was caught a t about
2700 m and c a r r i e d about 200 m v e r t i c a l l y . The snowfield on which t h e y
were caught funneled i n t o a rock neck o f l e s s s t e e p t e r r a i n . A s a f e
rock and snow r o u t e e x i s t e d j u s t t o t h e west of t h i s a r e a .
COMMENT
This t r a g e d y was t h e r e s u l t o f i g n o r i n g b a s i c mountaineering r u l e s .
The c 1imbers had -1it t l e o r no mountaineering experience, were p o o r l y
d r e s s e d , and c a r r i e d inadequate equipment (one i c e axe and one 9 mm rope
f o r a p a r t y of 1 1 ) . I r r e s p o n s i b l e l e a d e r s h i p was d i s p l a y e d when t h e men
i n charge r e t u r n e d t o t h e camp and allowed t h e eleven boys t o continue
t h e climb. The p a r t y had n e i t h e r asked f o r a d v i c e n o r r e g i s t e r e d ,
although it appeared t o b e aware o f t h i s requirement i n a National Park.
T r a v e l l i n g on and below snowfields and snow g u l l i e s w i t h s o u t h e r n
exposure i n t h e a f t e r n o o n o f a sunny, warm day was a s e r i o u s mistake.
Climbs i n such t e r r a i n must b e made i n t h e e a r l y hours of t h e day,
b e f o r e t h e snow l o s e s s t r e n g t h and becomes u n s t a b l e under t h e i n f l u e n c e
of t h e sun.
F i g u r e 1 South f a c e of Mount Temple, showing l o c a t i o n o f avalanche
11 J u l y 1955 and a c c e s s r o u t e of r e s c u e p a r t y . Victims
were found a t lower end o f a v a l a n c h e . I t i s no,t known
e x a c t l y where t h e avalanche s t a r t e d o r where t h e p a r t y
was c a u g h t . (Photo c o u r t e s y Parks Canada)
MARMOT BASIN, JASPER, ALBERTA
11 MARCH 1956
One s k i e r k i l l e d
WEATHER
Heavy w i n t e r snowfall and high winds had been experienced i n t h e
Marmot Basin a r e a p r i o r t o 11 March. Recent snowfall and h i g h temperat u r e s were i n c r e a s i n g t h e hazard i n a r e a s t h a t had n o t a l r e a d y produced
avalanches.
ACCIDENT SUMMARY
A group of s k i e r s l e f t P o r t a l Creek a t 0930 h , 11 March, f o r a
d a y ' s h i k i n g and s k i i n g a t Marmot Basin. The group was informed by a
park warden a s t o which a r e a s i n t h e Basin were considered s a f e f o r
s k i i n g and which were dangerous and should be avoided. One bowl - l a t e r
t h e a c c i d e n t s i t e - was pointed o u t a s p a r t i c u l a r l y dangerous and had
been flagged a s such.
One couple, a f t e r s k i i n g a l l day i n t h e s a f e a r e a on t h e r i d g e t o
t h e r i g h t o f t h e bowl, decided t o h i k e f o r t h e l a s t r u n . A t 1530 h they
were observed t o swing l e f t from t h e t r a i l i n t o t h e rocky a r e a above and
b e s i d e t h e bowl. Leading by about 80 m and moving o u t o n t o t h e
avalanche s l o p e , t h e man shouted back t o h i s companion t o w a i t w h i l e h e
s k i t e s t e d t h e s l o p e . He then s k i e d p a r t way down and f e l l . A t t h i s ,
t h e snow cracked above him and a l a r g e avalanche engulfed him.
RESCUE
The a c c i d e n t was observed from t h e bottom and a r e s c u e p a r t y was
immediately o r g a n i z e d . A f t e r i n s t r u c t i n g a p a t r o l l e r t o b r i n g a d d i t i o n a l
f i r s t - a i d equipment, t h e park warden began t o climb w i t h a r e s c u e s l e d
k i t and s h o v e l . On t h e way up he met t h e companion of t h e v i c t i m who
indicated the last-seen point.
Upon a r r i v a l a t t h e a c c i d e n t s i t e a t 1555 h a s u r f a c e s e a r c h f o r
c l u e s was i n i t i a t e d and l i k e l y a r e a s were probed a t random w i t h t r a i l
markers which had been c o l l e c t e d on t h e way. The w i t n e s s was asked t o
a c t a s a look-out i n c a s e o t h e r avalanches should o c c u r .
Random probing was continued u n t i l 1625 h, when probe l i n e s were
s e t up n e a r t h e t o p o f t h e d e p o s i t i o n a r e a . The s e a r c h e r s worked i n t h e
g e n e r a l f a l l l i n e from t h e l a s t - s e e n p o i n t . Reinforcements s t a r t e d t o
a r r i v e a t 1800 h and another probe l i n e was s e t up a d j a c e n t t o t h e
previous one, b u t working up t h e d e b r i s . A f t e r probing o v e r a d i s t a n c e
of about 60 m, probe c o n t a c t was made. The r e s c u e r s dug down and found
f i r s t a s k i and then t h e v i c t i m b u r i e d under approximately 2.5 m of
snow a t 1935 h.
AVALANCHE
This was a l a r g e d r y s l a b avalanche t r i g g e r e d by t h e weight o f t h e
s k i e r and perhaps t h e c u t t i n g e f f e c t of h i s t r a v e r s e . The small bowl
h e l d a concave s l o p e , which was i n t h e l e e of t h e p r e v a i l i n g wind. The
maximum depth o f f r a c t u r e was 1 m and t h e depth of t h e d e p o s i t e d
avalanche snow ranged between 4 and 6 m.
COMMENT
The avalanche occurred i n a known danger a r e a about which t h e v i c t i m ,
a n experienced mountaineer, was f u l l y aware. The d e s i r e t o make a f r e s h
t r a c k i n powder snow overcame c a u t i o n w i t h t r a g i c r e s u l t s .
-
PREVAILING
WIND
E SLOPE
FOLLOW-UP
Figure 2
PARTY
Sketch o f avalanche a t Marmot Basin, 11 March 1956
RICHARDSON RIDGE, LAKE LOUISE, ALBERTA
1 7 MARCH 1957
One s k i e r k i l l e d
Observations a t Lake Louise Townsite. 1530 m ASL
Temper a t u r e
OC
Date
Max
Min
1 3 March
1
-27
14 March
1
-25.5
15 March
3.5
-14.5
16 March
6.5
-19.5
17 March
6
-
5.5
High day temperatures had p r e v a i l e d f o r about t h r e e weeks. About
80 cm of new snow had f a l l e n i n t h e Temple Lodge a r e a over t h e previous
week.
ACCIDENT SUMRY
The a c c i d e n t was n o t observed. A s k i e r , t r a v e l l i n g a l o n e , had
presumably l e f t Temple Lodge on 1 7 March. Tracks i n d i c a t e d t h a t h e s k i e d
up C o r r a l Creek and about 1 . 5 km from Temple Lodge proceeded t o climb an
o l d avalanche p a t h a t t h e end o f Richardson Ridge. Presumably he was
caught by t h e avalanche w h i l e climbing.
RESCUE
The s k i e r was r e p o r t e d missing t o t h e Park Warden S e r v i c e a t 0945 h
on 18 March. A t 0955 h an advance s e a r c h p a r t y l e f t Temple Lodge and,
following t h e t r a c k s , a r r i v e d a t 1030 h a t a f r e s h avalanche d e p o s i t
where t h e t r a c k s disappeared. Follow-up p a r t i e s a r r i v e d a s h o r t time
l a t e r and a f u l l s e a r c h of t h e avalanche was made. The v i c t i m was found
b u r i e d about 20 m from t h e t o e o f t h e avalanche d e p o s i t a t approximately
1600 h . The p r o b a b l e cause o f d e a t h was s u f f o c a t i o n .
AVALANCHE DATA
High temperature a t t h e south-facing s l o p e on a sunny, warm day
appears t o have been t h e p r i n c i p a l cause of t h e avalanche. I t was a
l a r g e , f u l l - d e p t h avalanche t h a t involved b o t h o l d and new snow l a y e r s .
The avalanche p a t h h a s a s o u t h - e a s t e r l y a s p e c t and i s i n t h e l e e of t h e
p r e v a i l i n g wind. The s t a r t i n g zone has an i n c l i n e of about 40 deg and
is s l i g h t l y concave, w i t h a bench below o f 20 deg i n c l i n e . The deposited
avalanche snow had components of hard and s o f t snow and covered an a r e a
about 120 m by 120 m.
COMMENT
The s k i e r made t h e mistake o f climbing alone i n hazardous t e r r a i n .
Anyone a l o n e has very l i t t l e chance o f being rescued if b u r i e d i n an
avalanche.
BOW SUMMIT, BANFF NATIONAL PARK, ALBERTA
23 NOVEMBER 1958
Two s k i e r s k i l l e d
A snow cover more than 30 cm deep, d e p o s i t e d i n e a r l y October, had
s e t t l e d and formed a hard c r u s t . Unusually heavy snowfall followed i n
November w i t h 30 cm o f new snow i n t h e f o u r days p r i o r t o t h e 23rd.
Conditions were considered t o b e w i n d i e r than u s u a l f o r t h a t time o f
y e a r . On 23 November t h e wind was from t h e n o r t h a t 15 km/h and t h e
temperature was -8OC.
ACCIDENT SUMMARY
A t 1315 h on 23 November a park warden on s k i p a t r o l a t Peyto P o i n t
parking l o t observed a n avalanche on t h e r i d g e t o t h e north-west o f
Mount Thompson. He d i d n o t s e e anyone involved, b u t he and a n o t h e r
warden climbed on s k i s w i t h s k i n s t o t h e s i t e f o r a f u r t h e r r o u t i n e
check.
RESCUE
A t t h e s i t e t h e wardens could n o t observe any t r a c k s , and a h a s t y
s e a r c h of t h e avalanche d e p o s i t gave no i n d i c a t i o n of anyone being
b u r i e d . Two s k i e r s approached, however, and s a i d they thought two
f r i e n d s might have been i n t h e a r e a .
A second h a s t y s e a r c h w i t h random probing was c a r r i e d o u t and
w i t h i n 5 min a v i c t i m was l o c a t e d approximately 1.2 m below t h e s u r f a c e .
A t 1355 h t h e v i c t i m was dug o u t ; he was unconscious and n o t b r e a t h i n g ,
and a r t i f i c i a l r e s p i r a t i o n was commenced. A t 1400 h t h e warden i n
charge s e n t f o r f u r t h e r a s s i s t a n c e and equipment. A p a r t y of 20
v o l u n t e e r s a r r i v e d 15 min l a t e r and was organized i n t o probe l i n e s . The
a r t i f i c i a l r e s p i r a t i o n on t h e v i c t i m was continued u n t i l 1500 h w i t h no
success.
A t 1610 h t h e body o f t h e second v i c t i m was l o c a t e d 1.8 m below t h e
s u r f a c e . He showed no s i g n s o f l i f e and a r t i f i c i a l r e s p i r a t i o n proved
o f no a v a i l ,
AVALANCHE
The avalanche was caused by a combination of new snow, wind, and
poor bonding o f t h e new snow on t h e c r u s t . I t was a d r y s l a b avalanche
t h a t s t a r t e d a t approximately 2430 m ASL. The f r a c t u r e v a r i e d from 75
t o 85 cm i n depth and t h e bed s u r f a c e was t h e hard c r u s t . The s l o p e has
a g r a d i e n t o f 40 deg n e a r t h e f r a c t u r e l i n e and a NE a s p e c t .
COMMENT
S k i e r s f r e q u e n t l y u s e t h e a r e a a t t h e beginning o f t h e w i n t e r
because enough snow f o r s k i i n g can u s u a l l y b e found t h e r e b e f o r e o t h e r
s k i a r e a s open.
The n o r t h e r n edge o f t h e s l o p e was flagged, marking i t a s an
avalanche a r e a . I t i s n o t known whether t h e two v i c t i m s were beyond t h e
f l a g s o r n o t when t h e avalanche occurred, f o r t h e avalanche was l a r g e r
t h a n u s u a l and wiped o u t t h e f l a g s . S k i t r a c k s w i t h a climbing switchback t r a v e r s e and s k i n s on t h e s k i s o f t h e v i c t i m s i n d i c a t e t h a t t h e y
were climbing when t h e a c c i d e n t o c c u r r e d . Probably t h e y had e n t e r e d t h e
s l o p e t o f i n d deep snow because winds had b a r e d t h e rock on t h e normal
ridge route.
Obviously t h e two s k i e r s had n o t r e a l i z e d t h a t t h e snow was i n an
u n s t a b l e c o n d i t i o n . T h e i r r o u t e , a s t e e p s l o p e a t t h e l e e s i d e of t h e
r i d g e , was p o o r l y chosen. The r i d g e should have been used f o r climbing
and f o r downhill s k i i n g .
Remarkable i s t h e r a p i d d i s c o v e r y o f t h e f i r s t v i c t i m owing t o t h e
a l e r t n e s s and i n i t i a t i v e o f t h e p a r k wardens. I t i s u n f o r t u n a t e t h a t
h t h e f i r s t v i c t i m was
i n s p i t e o f b e i n g b u r i e d f o r l i t t l e more than
n o t found a 1i v e
.
Figure 3 ( a )
View o f a v a l a n c h e , Bow Summit,
23 November 1958,
(Photo c o u r t e s y Parks Canada)
2nd
Figure 3 ( b )
PROBE
L l NE
@
VICTIMS F O U N D
X X
W A R N I NG
--- V I C T I M S S
K I TRA C K S
FLAGS
Sketch of avalanche, Bow Summit, 23 November 1958
TOBY CREEK, INVERMERE, B .C
.
30 JANUARY 1960
One person b u r i e d
WEATHER
Heavy snow f a 11s were f o l lowed by unseasonably high temperatures on
Saturday, 30 January, r e a c h i n g a maximum o f 1 0 ' ~w i t h a n o v e r n i g h t
minimum o f Z°C.
ACCIDENT SUWRY
A b u l l d o z e r was c l e a r i n g an avalanche on t h e Toby Creek Road
17 m i l e s northwest of Invermere, B.C., one highway employee a c t i n g a s
flagman and avalanche lookout. Suddenly a n o t h e r avalanche came down
The machine o p e r a t o r saw t h e avalanche
from t h e " L i t t l e Dragon S l i d e
b u t was unable t o warn t h e flagman. The o p e r a t o r escaped unharmed, b u t
t h e flagman disappeared i n t h e snow. The time was approximately 1300 h .
."
RESCUE
The machine o p e r a t o r c o n t a c t e d t h e RCMP i n Invermere and o t h e r highway personnel i n t h e a r e a , t h e n commenced a s e a r c h of t h e d e p o s i t s .
Within an hour about 40 men were s e a r c h i n g a t random w i t h s h o v e l s .
Kootenay National Park s e a r c h and r e s c u e personnel were c a l l e d by t h e
RCMP and equipped w i t h probes and s h o v e l s . They were joined by a doctor
i n Invermere. A s they proceeded up t h e Toby Creek Road a n o t h e r
avalanche came down between t h e i r t r u c k and t h e d o c t o r ' s c a r .
When t h e National Parks s t a f f a r r i v e d some s e a r c h e r s were organized
i n a probe l i n e n e a r t h e l a s t - s e e n p o i n t and some were d e l e g a t e d t o a
random s e a r c h o f t h e d e p o s i t s . More probes were r e q u e s t e d from Invermere.
Once it was thought a shout had been heard n e a r t h e l a s t - s e e n p o i n t , b u t
t h e a r e a was searched f o r o v e r an hour t o no a v a i l .
Probing continued u n t i l 1930 h when t h e r e s c u e r s were c a l l e d off
because o f t h e h a z a r d from f u r t h e r avalanches i n t h e d a r k n e s s . L i t t l e
hope was h e l d o f f i n d i n g t h e v i c t i m a l i v e . A t daybreak on 31 January
probing was resumed and t h e whole a r e a had been probed by 1215 h . A s t h e
avalanche h a z a r d was a g a i n mounting t h e chance o f f i n d i n g t h e man a l i v e
was weighed a g a i n s t t h e danger t o r e s c u e r s from f u r t h e r s l i d e s , and i t
was decided t o c a l l t h e men o f f .
%o b u l l d o z e r s began t o remove t h e snow from t h e road, and i t was
hoped t h a t t h e body might b e found. A f t e r n e a r l y a n hour t h e machine on
t h e west s i d e o f t h e avalanche uncovered a h o l e from which a n arm waved
f e e b l y . The flagman was hauled o u t a l i v e , exhausted and s u f f e r i n g from
f r o s t b i t e . H i s wet c l o t h e s were changed and h e was s e n t t o t h e h o s p i t a l
i n Invermere. The time of recovery was 1430 h, 31 January.
AVALANCHE
Heavy snow f a 1 1 followed by above-freezing temperatures l e d t o t h e
formation o f a wet avalanche. The d e p o s i t was e s t i m a t e d t o b e 6 t o 12 m
deep i n p l a c e s .
COMMENT
A t t h e time t h e avalanche occurred t h e flagman was s t a n d i n g n e a r a
bank c u t i n previous snow removal o p e r a t i o n s . T h i s probably p r o t e c t e d
him and prevented h i s b e i n g swept from t h e road, b u t i t a l s o l e d t o an
extremely deep b u r i a l , deeper t h a n t h e 3 m probing rods. An a i r passage
from t h e s u r f a c e n e a r t h e old bank a s s i s t e d i n t h e man's s u r v i v a l . The
c a l l heard d u r i n g t h e s e a r c h may w e l l have been t h e v i c t i m ' s . Another
f a c t o r favourab l e t o s u r v i v a l was t h e v i c t i m 1s heavy c l o t h i n g , which
maintained body h e a t .
During t h e s e a r c h t h e v i c t i m ' s dog was brought i n , b u t he was
u n s u c c e s s f u l because he was u n t r a i n e d and confused by t h e l a r g e number
of r e s c u e r s
.
MOUNT ATHABASCA, JASPER NATIONAL PARK, ALBERTA
23 MAY 1960
Tho climbers i n j u r e d
WEATHER
About 60 cm o f new snow f e l l i n t h e a r e a o f t h e Columbia I c e f i e l d s
during t h e two days p r i o r t o 23 May. Everyone a t t h e C h a l e t was s t r o n g l y
advised a g a i n s t s k i i n g o r climbing i n t h e a r e a because of a high
avalanche hazard. A s t r o n g SE wind w i t h f r e e z i n g temperatures o v e r n i g h t
had formed numerous s l a b s , and sun and above-freezing temperatures on
23 May f u r t h e r i n c r e a s e d t h e hazard.
ACC I DENT SUMMARY
Three climbers, aware o f t h e dangers, decided t o a t t e m p t t o climb
Mount Athabasca by t h e NW f a c e . Deep s o f t snow made movement v e r y slow
and d i f f i c u l t . Unable t o climb w i t h s k i s t h e y l e f t them on t h e g l a c i e r
and walked s t r a i g h t up a s t e e p g u l l y on t h e NW f a c e . The p a r t y was
approaching an e l e v a t i o n o f 2650 m when t h e l e a d e r t r i g g e r e d an
avalanche. A l l t h r e e climbers were caught and c a r r i e d down t o about t h e
2430 m e l e v a t i o n where a l l were a t l e a s t p a r t l y b u r i e d .
RESCUE
One man was a b l e t o d i g himself o u t and a i d h i s companions; one had
a n i n j u r e d f o o t , t h e o t h e r a broken femur. The u n i n j u r e d member t h e n
l e f t f o r h e l p and a r r i v e d a t t h e I c e f i e l d C h a l e t a t 1300 h , 4 h a f t e r
t h e a c c i d e n t . By 1330 h t h e National Parks Alpine S p e c i a l i s t a t t h e
C h a l e t l e f t , w i t h s k i s , f o r t h e a c c i d e n t s i t e , r e a c h i n g i t a t 1530 h .
A f t e r a d m i n i s t e r i n g f i r s t - a i d , he assembled a s l e d u s i n g h i s own s k i s
and loaded t h e more b a d l y i n j u r e d v i c t i m on i t .
The u n i n j u r e d p a r t y member had been i n s t r u c t e d t o remain a t t h e
C h a l e t t o d i r e c t t h e follow-up column t o t h e s i t e . I n s p i t e of t h i s h e
l e f t and climbed back t o t h e avalanche a l o n e . The assembled follow-up
column, t h e r e f o r e , d i d not know where t o go, h e s i t a t e d , b u t f i n a l l y found
t h e t r a c k s and followed them, meeting t h e r e t u r n i n g Alpine S p e c i a l i s t a t
1700 h . Together t h e y moved t h e v i c t i m s t o an ambulance a t t h e road.
AVALANCHE
T h i s was a s l a b avalanche, s t a r t e d on a w e s t - f a c i n g l e e s l o p e j u s t
above t h e g u l l y , w i t h a f r a c t u r e over 100 m wide. The s t a r t i n g zone
has a n average g r a d i e n t o f approximately 50 deg and s t e e p c l i f f s . The
p a r t y was c a r r i e d down over 200 m v e r t i c a l d i s t a n c e i n a g u l l y .
COMMENT
Recent snowfall and s t r o n g wind had obviously formed u n s t a b l e snow,
and under t h e s e c o n d i t i o n s climbing a s t e e p s l o p e on t h e l e e s i d e o f a
mountain was extremely hazardous. P r o t r u d i n g rooks i n t h e g u l l y u s u a l l y
i n c r e a s e t h e r i s k o f i n j u r y t o anyone caught i n an avalanche, and t h e
p a r t y was lucky t o e s c a p e w i t h r e l a t i v e l y l i t t l e harm.
The unauthorized d e p a r t u r e o f t h e w i t n e s s from t h e C h a l e t b e f o r e
t h e follow-up p a r t y was assembled could have had s e r i o u s consequences if
t h e v i c t i m s had been b u r i e d o r c r i t i c a l l y i n j u r e d .
MOUNT ATHABASCA, JASPER NATIONAL PARK, ALBERTA
20 J U N E 1960
One climber i n j u r e d
About 30 cm o f new snow had r e c e n t l y f a l l e n on Mount Athabasca
w i t h some wind a c t i o n . On 20 J u n e winds were calm, t h e sky was o v e r c a s t
and l i g h t r a i n was f a l l i n g a t high temperatures. High avalanche hazard
prevailed i n the area.
ACCIDENT SUMMARY
Two v e r y experienced climbers decided t o climb t h e summit of Mount
Athabasca o v e r t h e SE r i d g e on 20 June i n s p i t e o f b e i n g advised of t h e
h i g h avalanche hazard. When they reached about t h e 2900 m l e v e l an
avalanche came down from t h e g u l l y above, pushed them off t h e r i d g e ,
and c a r r i e d them about 300 m v e r t i c a l l y o v e r s t e e p t e r r a i n and c l i f f s .
RESCUE
The a c c i d e n t occurred a t approximately 1100 h and was r e p o r t e d a t
1700 h. The N a t i o n a l Parks Alpine S p e c i a l i s t a t t h e I c e f i e l d s C h a l e t
l e f t f o r t h e scene a t 1730 h and found t h e v i c t i m s on t h e lower p a r t of
t h e SE r i d g e a t 1930 h . One v i c t i m had s u s t a i n e d an open c h e s t wound
and broken r i b s , b u t h i s companion had rendered f i r s t a i d and most of
t h e b l e e d i n g had stopped. The v i c t i m was taken t o t h e road by toboggan
and s e n t by ambulance t o h o s p i t a l i n Banff.
AVALANCHE
This avalanche was a s l a b type, r e l e a s i n g n a t u r a l l y from a g u l l y
above t h e c l i m b e r s 1 r o u t e .
COMMENT
The a c c i d e n t occurred i n t h e same a r e a and under circumstances
s i m i l a r t o t h o s e of t h e a c c i d e n t on 23 May 1960.
MOUNT WHALEBACK, YOHO NATIONAL PARK, B .C
.
30 DECEMBER 1962
One s k i e r k i l l e d
WEATHER
On 30 December it was snowing h e a v i l y i n t h e Yoho Valley, w i t h low
cloud obscuring t h e peaks.
ACCIDENT SUMMARY
A group o f 14 u n i v e r s i t y s t u d e n t s had s k i e d t o t h e Twin F a l l s C h a l e t
i n t h e Yoho Valley on 28 December. They planned t o go s k i t o u r i n g i n t h e
a r e a while s t a y i n g a t t h e C h a l e t , had d i s c u s s e d t h e avalanche c o n d i t i o n s
w i t h t h e park wardens, and were w e l l equipped.
On 30 December t h e group was s c a t t e r e d a l o n g a climbing t r a v e r s e on
t h e NE s l o p e of Mount Whaleback - f o u r about t h e 2100 m l e v e l , seven
around 2000 m, and t h r e e i n between. A t approximately 1200 h an
avalanche swept down from t h e clouds, e n g u l f i n g t h e p a r t y .
RESCUE
A l l 14 s k i e r s found themselves a t l e a s t p a r t l y b u r i e d when t h e
avalanche came t o a s t o p . A f t e r 20 min o f d i g g i n g each o t h e r o u t i t was
determined t h a t one s k i e r ( a woman) was missing. Many of t h e group
were i n shock, b u t t h e l e a d e r managed t o o r g a n i z e probing with s k i p o l e s
and t h e missing s k i e r was discovered a f t e r 30 t o 40 min. She was b u r i e d
under 1 m of packed avalanche snow, unconscious, and n o t b r e a t h i n g a t
t h e time o f d i s c o v e r y . A r t i f i c i a l r e s p i r a t i o n was a p p l i e d f o r an hour
and a h a l f without s u c c e s s . The v i c t i m was l a t e r determined t o have
d i e d of s u f f o c a t i o n .
One member of t h e p a r t y l e f t t h e n e x t morning w i t h word of t h e
a c c i d e n t and park wardens and RCMP o f f i c e r s a r r i v e d a t t h e Chalet on
New Year's Eve w i t h e x t r a snowshoes t o r e p l a c e equipment l o s t i n t h e
avalanche. On 1 January they d e p a r t e d w i t h t h e body o f t h e v i c t i m . The
remainder of t h e group l e f t t h e a r e a on 2 January.
AVALANCHE
The avalanche s t a r t e d a t approximately 2500 m on a NE s l o p e and
caught t h e s k i e r s a t approximately 2100 m . I t was probably t r i g g e r e d by
overloading from w i n d - d r i f t e d snow. The s t a r t i n g zone has an i n c l i n e of
approximately 35 deg and t h e lower s c r e e s l o p e s where t h e p a r t y was
caught one of about 30 deg.
T h i s was probably a medium s i z e , dry-snow avalanche. I n 1972 a
very l a r g e avalanche on t h e same s l o p e r a n much f u r t h e r and wiped o u t a
b r i d g e a t Twin F a l l s .
COMMENT
The group was e v i d e n t l y climbing t h e avalanche p a t h a t t h e time of
t h e a c c i d e n t and had not followed b a s i c s a f e t y measures, which r e q u i r e
t h a t a minimum number o f p a r t y members should be i n t h e path of a n
avalanche s i m u l t a n e o u s l y . Such p r e c a u t i o n s must b e adhered t o more
s t r i c t l y d u r i n g hazardous p e r i o d s such a s storms w i t h l i m i t e d v i s i b i l i t y .
TEMPLE SKI AREA, LAKE LOUISE, ALBERTA
28 APRIL 1963
One s k i e r b u r i e d
WEATHER
Observations a t Lake Louise Townsite, 1530 m ASL
Temperature
Precipitation
O c
Date
Max
Min
23 A p r i l
5.5
-
24 A p r i l
9.5
-2
25 A p r i l
13.5
-5
26 A p r i l
16.5
-3.5
27 A p r i l
13.5
-4.5
mm
9
2.5
On 28 A p r i l t h e weather was warm and calm and s e v e r a l new avalanches
were observed i n t h e Temple s k i a r e a .
ACC I DENT SUMMARY
A s two s k i e r s were t r a v e r s i n g t h e west s l o p e o f Larch Ski H i l l , t h e
second s k i e r n e a r t h e t o p , a n avalanche r e l e a s e d and caught him. The
v i c t i m ' s companion was c l e a r o f t h e avalanche and immediately r e p o r t e d
t h e a c c i d e n t t o t h e S k i P a t r o l . The time was 1155 h .
RESCUE
An advance p a r t y l e d by a s k i patrolman was d i s p a t c h e d a t 1205 h and
a r r i v e d a t t h e s i t e a t 1215 h . The w i t n e s s accompanied t h i s p a r t y and
i n d i c a t e d t h e p o i n t a t which h e had l a s t seen t h e v i c t i m . A follow-up
p a r t y o f 45 v o l u n t e e r s was d i s p a t c h e d a t 1230 h and a r r i v e d a t t h e scene
a t 1255 h.
A group o f park wardens t r a v e l l i n g from Banff by c a r i n t e r c e p t e d a
r a d i o c a l l concerning t h e avalanche a c c i d e n t and a l s o proceeded
immediately t o t h e s i t e . When t h e y a r r i v e d t h e d e p o s i t a r e a had been
probed twice, and a t h i r d probe and t r e n c h i n g p a t t e r n had been s t a r t e d .
The warden i n charge decided t h a t t h e w i t n e s s ' s r e p o r t must b e i n c o r r e c t
and ordered a s e a r c h above t h e l a s t - s e e n p o i n t . When t h e r e s c u e r s worked
up t h e s l o p e and reached s c a t t e r e d small avalanche d e p o s i t s , t h e y heard
a c r y f o r h e l p . Answering and moving i n t h e d i r e c t i o n of t h e c r y a
warden came upon t h e v i c t i m l i g h t l y b u r i e d i n a t r e e w e l l w i t h j u s t h i s
h a i r showing. The b u r i e d s k i e r was 180 m upslope from t h e l a s t - s e e n p o i n t
i n d i c a t e d by t h e w i t n e s s . He was f r e e d a t 1540 h and t r a n s p o r t e d on a
toboggan t o t h e Temple Chalet f o r f u r t h e r f i r s t a i d . He was l a t e r
r e l e a s e d w i t h no s i g n i f i c a n t i n j u r i e s .
AVALANCHE
The avalanche was caused by a l o s s o f s t r e n g t h i n t h e snowcover a s a
r e s u l t of continuous h i g h temperatures. I t s t a r t e d a s a wet f u l l - d e p t h
s l a b a t a n a l t i t u d e o f 2180 m, j u s t below t h e t r e e l i n e on a n o r t h e a s t
s l o p e of 25 t o 30 deg. The ground was broken s h a l e w i t h small ledges and
s c a t t e r e d t r e e s . I t had been covered by about 75 cm of snow, which was
n e a r l y a l l removed by t h e avalanche.
COMMENT
The a r e a where t h e avalanche occurred was r a r e l y s k i e d , was known a s
an avalanche s l o p e and posted a s such.
The b u r i e d v i c t i m could h e a r t h e r e s c u e r s working below him, b u t
only when a r e s c u e r was c l o s e t o him could he make himself h e a r d . The
confusion o f t h e eye w i t n e s s about t h e l a s t - s e e n p o i n t could have l e d t o
tragedy, b u t f o r t u n a t e l y t h e v i c t i m was n o t b u r i e d deeply and a l l ended
w e l l . The c a s e i l l u s t r a t e s t h e f a c t t h a t eye w i t n e s s r e p o r t s must b e
assessed with caution.
Figure 4
Temple s k i a r e a , 28 A p r i l 1963. View o f
avalanche from t h e s i d e
o Last-seen p o i n t i n d i c a t e d by r e t u r n i n g
eyewitness
x Missing s k i e r found
(Courtesy Parks Canada)
Figure 5
Temple s k i a r e a , 28 A p r i l 1963. View from
the front.
Avalanche snow was 4 t o 5 m
deep (Courtesy Parks Canada)
GRANDUC MINE, STEWART, B.C.
18 FEBRUARY 1965
Twenty-six workmen k i l l e d ; twenty workmen i n j u r e d ,
destroyed
buildings
WEATHER
Observations a t Stewart, 45 m ASL
Precipitation
mm
Temperature
OC
Date
Max
Min
11 February
3
-10
12 February
1.5
-
13 February
1.5
-12
14 February
2
- 10
15 February
3
16 February
2
17 February
3
18 February
2
-
3
7
4.5
5
4.5
I n December 1964 t h e c l i m a t e s t a t i o n s a t S t e w a r t , B . C . , Ketchikan,
Alaska, and Cape Annette,Alaska, recorded temperatures 5.5 C deg below
normal and p r e c i p i t a t i o n 35 p e r c e n t below normal. Between 13 and 31
December o n l y 1 2 mm o f p r e c i p i t a t i o n were recorded a t S t e w a r t , with overn i g h t temperatures r a n g i n g down t o -25OC. Both t h e p r e c i p i t a t i o n and t h e
temperature remained low i n t h e f i r s t week o f January.
I n February heavy s n o w f a l l s followed t h e e a r l y c o l d d r y weather.
For s e v e r a l days p r i o r t o 18 February a g r e a t s u b - a r c t i c storm raged and
an e s t i m a t e d 4 . 3 m o f snow f e l l a t t h e Granduc Mine.
ACC I DENT SUMMARY
.
The Granduc Mine i s 30 km northwest o f S t e w a r t , B .C , n e a r t h e
Alaska b o r d e r ; t h e Leduc Camp o f t h e mine was l o c a t e d on a moraine a t t h e
j u n c t i o n o f t h e North and South Forks o f t h e Leduc G l a c i e r and was
a c c e s s i b l e only over g l a c i e r covered t e r r a i n .
A t 0957 h on 18 February an avalanche d e s t r o y e d t h e s o u t h e r n p o r t i o n
of t h e camp and t h e b u i l d i n g s surrounding t h e mine p o r t a l , n o t q u i t e
blocking t h e p o r t a l . I n t h e camp p r o p e r t h e r e were f o u r bunkhouses, a
r e c r e a t i o n h a l l , warehouse, f i r s t - a i d b u i l d i n g and temporary h o s p i t a l ,
a small h e l i c o p t e r hangar w i t h workshop, and t e n s m a l l e r b u i l d i n g s .
A f t e r t h e avalanche only t h e bunkhouses, mine o f f i c e , warehouse, t h e
f i r s t - a i d b u i l d i n g / h o s p i t a l were l e f t i n t a c t . Between t h e camp and t h e
p o r t a l , and a t t h e p o r t a l i t s e l f , t h e r e were a l a r g e power-house, a l a r g e
workshop and new and o l d d r y b u i l d i n g s . A l l were demolished.
There were 154 men i n t h e Leduc Camp ; 68 o f them were caught i n t h e
avalanche. The o t h e r s were i n b u i l d i n g s t h a t were untouched o r were
working i n s a f e a r e a s o u t s i d e ; 21 men were working underground. The men
caught i n t h e avalanche were s h o v e l l i n g r o o f s , b u l l d o z i n g pathways,
digging o u t equipment and working on c o n s t r u c t i o n and machinery i n t h e
a r e a o-f t h e mine p o r t a l . One o f them was E i n a r Myllyla who was a l o n e i n
t h e c a r p e n t r y shop.
RESCUE
The avalanche d e s t r o y e d t h e power-plant, b u t w i t h i n minutes
a u x i l i a r y power was connected t o t h e r a d i o t r a n s m i t t e r and a d i s t r e s s
s i g n a l was s e n t t o t h e S t e w a r t mine o f f i c e . S u r v i v o r s , f o r t u n a t e l y
i n c l u d i n g a d o c t o r and a f i r s t - a i d a t t e n d a n t , commenced r e s c u e o p e r a t i o n s
immediately. A t t h e time of t h e d i s a s t e r 15 men were working o u t s i d e t h e
p o r t a l and a l l were b u r i e d . The mine s h i f t b o s s , who had f o r t u n a t e l y
been on t h e s u r f a c e j u s t b e f o r e , knew t h e approximate p o s i t i o n s o f a l l
t h e s e men and s e t t h e underground crew working i n t h e hope of uncovering
s u r v i v o r s . A l l 15 were found f a i r l y quickly; s i x were a l i v e , b u t n i n e
were dead on recovery.
A s most s u r v i v o r s i n t h e r e s t o f t h e camp were i n varying s t a t e s o f
shock and i n j u r y , t h e r e s c u e work was slow. Lack of proper equipment and
t h e ongoing storm hampered o p e r a t i o n s . Using b a r e hands, s h o v e l s and
makeshift equipment, 41 men were saved t h a t day, t h e l a s t one t o come o u t
a l i v e 5 1/2 h a f t e r t h e s l i d e .
The d i s t r e s s s i g n a l t o S t e w a r t was heard by t h e Alaska S t a t e P o l i c e
who immediately n o t i f i e d t h e RCMP i n P r i n c e Rupert. Mine o f f i c i a l s i n
S t e w a r t had o p e r a t i o n s w e l l under way, a r r a n g i n g f o r a h e l i c o p t e r b a s e
t o b e s e t u p and ground r e s c u e t o b e i n i t i a t e d . A s normal a i r a c c e s s t o
t h e mine from Stewart was s t i l l impossible, a h e l i c o p t e r b a s e was s e t up
a t t h e mouth o f t h e Chikamin River on t h e Alaska s i d e . Meanwhile ground
r e s c u e teams had l e f t by snowcat from t h e n e a r e s t road camp; although i t
would t a k e t h r e e days t o cover t h e rugged 55 km, t h i s might b e t h e o n l y
means of r e s c u e i f t h e a r e a remained c l o s e d by a i r .
The news was almost immediately i n t h e hands o f t h e p r e s s and
brought a i d from many q u a r t e r s o f B r i t i s h Columbia and Alaska. By 1700 h
o p e r a t i o n s a t t h e camp had become more organized : communications w i t h
Chikamin were e s t a b l i s h e d and a h e l i c o p t e r pad was bulldozed o u t o f t h e
d e b r i s i n f r o n t o f t h e wrecked mess h a l l . Unknown t o a l l , E i n a r Myllyla
l a y 3 m below t h e pad i n an i c y p r i s o n , conscious o f o p e r a t i o n s above him.
On 19 February t h e f i r s t h e l i c o p t e r was a b l e t o reach t h e camp from
t h e Chikamin River b a s e , a f t e r spending t h e n i g h t on a g l a c i e r between
t h e two s i t e s , f o r c e d down by weather. F u r t h e r machines brought
a d d i t i o n a l t r a i n e d r e s c u e personnel and t r a i n e d r e s c u e dogs. An
evacuation s h u t t l e t o Chikamin and Ketchikan was e s t a b l i s h e d .
The s e a r c h f o r s u r v i v o r s was g r e a t l y hampered by t h e mass of
wreckage i n t h e snow. Rescue dogs were confused by t h e maze of human
s c e n t s . Probing turned up o n l y more s c a t t e r e d m a t e r i a l . Poor
v i s i b i l i t y , snow, fog, and wind c o n t i n u a l l y hampered o p e r a t i o n s . For two
days, between f i t f u l comas, Myllyla could h e a r h e l i c o p t e r s landing and
t a k i n g o f f above him. F i n a l l y , on 21 February, a f t e r abandoning hope o f
f i n d i n g f u r t h e r s u r v i v o r s , c a r e f u l t r e n c h i n g o f t h e d e b r i s began w i t h
b u l l d o z e r s s h e a r i n g o f f o n l y a few i n c h e s a t a time. S p o t t e r s rode t h e
b l a d e t o watch f o r b o d i e s .
On t h a t a f t e r n o o n , while work p r o g r e s s e d i n t h e a r e a of t h e
h e l i c o p t e r pad, a l a r g e s e c t i o n o f snow sheared away, r e v e a l i n g a
b l i n k i n g Myllyla, who looked up a t a s t o n i s h e d s p o t t e r s saying "Don't move
me, I t h i n k my l e g s a r e frozen." He had been b u r i e d f o r 3 days, 6 h . He
was immediately t a k e n t o Ketchikan where a team o f d o c t o r s saved a l l b u t
t h e t o e s o f one f o o t and some f i n g e r s . The l a s t body was recovered by
mine personnel on 18 J u n e - l e a v i n g 26 dead and 20 i n j u r e d .
AVALANCHE
The d e t a i l s concerning t h i s avalanche a r e r a t h e r sketchy.
Montgomery Atwater, t h e e x p e r t flown i n a t t h e time of t h e d i s a s t e r ,
d e s c r i b e d t h e s t a r t i n g zone on Granduc Mountain a f t e r t h e avalanche
occurrence a s having "hardly enough snow t o c o v e r t h e brush ." H i s
a n a l y s i s o f t h e s i t u a t i o n was a s f o l l o w s :
"Abnormally low temperatures i n e a r l y w i n t e r were
accompanied by high winds which may have c r e a t e d uns t a b l e hard s l a b c o n d i t i o n s . I n February e x c e p t i o n a l l y
heavy storms d e p o s i t e d l a r g e q u a n t i t i e s o f snow on t h e
u n s t a b l e b a s e , u n t i l it f i n a l l y c o l l a p s e d y i e l d i n g a
l a r g e climax avalanche f a l l i n g some 2500 v e r t i c a l f e e t
onto t h e camp."
The p r e v a i l i n g winds i n t h e a r e a a r e u s u a l l y west o r southwest,
s c o u r i n g t h e s l o p e s a t Granduc Mountain. I n t h i s c a s e a n e a s t wind may
have loaded t h e s t a r t i n g zone w i t h deep snow.
COMMENT
The Granduc d i s a s t e r i s t h e l a r g e s t o f i t s t y p e t o have occurred i n
Canada s i n c e t h e Rogers Pass d i s a s t e r of 1910. The r e s c u e o p e r a t i o n ,
i n v o l v i n g so many d i v e r s i f i e d i n t e r n a t i o n a l groups, can only b e p r a i s e d
a s a massive e f f o r t on t h e p a r t o f many. Adverse weather c o n d i t i o n s and
geographic f a c t o r s o f t e r r a i n and l o c a t i o n made a l l o p e r a t i o n s most
difficult.
Winter observations o f Granduc Mountain had not been made p r i o r t o
t h e w i n t e r o f 1965 and no previous avalanche occurrences had been
observed t h a t w i n t e r . The camp was l o c a t e d on a moraine forming a
promontory, with t h e ad j a c e n t depression providing a n a t u r a l , probably
unplanned, avalanche c a t c h e r . A s t h e camp grew it p r o l i f e r a t e d down from
t h e moraine, exposing more and more b u i l d i n g s . Furthermore, t h e mine
p o r t a l was i n t h e t r a c k o f l a r g e avalanches. Avalanche c o n t r o l was not
a p p l i e d here p r i o r t o t h e d i s a s t e r , b u t a l a r g e - s c a l e program was l a t e r
introduced f o r t h e p r o t e c t i o n o f t h e camps and access road. During t h e
rescue o p e r a t i o n h e l i c o p t e r bombing a t Granduc Mountain was c a r r i e d o u t
by M. Atwater, probably t h e f i r s t time t h i s c o n t r o l method was used.
B I B L IOGRAPHY
1)
Atwater, M.M.
2)
Province o f B r i t i s h Columbia. Annual Report o f t h e Minister of
Mines and Petroleum Resources f o r 1965, V i c t o r i a , B . C .
The Avalanche Hunters, McRae Smith, 1968.
O U T L I N E OF
+tLANCHE
P
/
AREA OF AVALANCHE
I N V O L V E D AT LEAST
O N E SQUARE MILE
MlNE
A
WORKINGS
/
LEDUC
GLAC IER
A
S O U T H /F O R K
I
Figure 6
Plan o f Leduc Camp, Granduc Mine (not t o s c a l e ) .
( B r i t i s h Columbia Department of Mines and
Petroleum Resources, Annual Report, 1965)
GRANDUC
MOUNTAIN
AVALANCHE STARTED
7 5 0 m ABOVE PORTAL.-
/
O
EL t o 9 4 m
I /
I
I
II
1/
L
II
EL 9 4 2 m O M l N E
I ] WORKINGS
MlNE
PORTAL
'I
It
\
I1
Figure 7
Avalanche p r o f i l e , Granduc Mine (not t o s c a l e ) .
( B r i t i s h Columbia Department of Mines and
Petroleum Resources, Annual Report, 1965)
MOUNT NORQUAY, BANFF, ALBERTA
28 FEBRUARY 1965
One s k i e r k i l l e d
WEATHER
Observations a t Banff Townsite. 1655 m ASL
Date
Temperature
"C
Max
M in
24 February
0.5
-10
25 February
6.1
26 February
3.5
-
New Snow
Precipitation
cm
rnm
3.5
T
4.5
6.8
27 February
-4
-13
28 February
-5.5
-18.5
21.1
1.3
The mean maximum temperature a t Banff t o w n s i t e f o r December 1964 was
-10.4OC, t h e minimum -19.S°C.
These temperatures f a l l considerably below
t h e 1949-70 means: maximum -8. S°C, minimum -13. O°C. T o t a l p r e c i p i t a t i o n
i n December 1964 and i n January 1965 was considerably below t h e 1949-70
mean.
ACCIDENT SUMMARY
Two s k i e r s , b o t h e x p e r t s , were s k i i n g from t h e M t . Norquay c h a i r l i f t
i n t o a g u l l y n o r t h of t h e Lone Pine Run. The l e a d e r t r i g g e r e d an
avalanche and h i s companion saw him disappear i n t h e moving snow. The
time was 1230 h.
RESCUE
The w i t n e s s climbed back t o t h e p a t r o l hut a t t h e t o p of M t . Norquay
where he r e p o r t e d t h e a c c i d e n t a t 1235 h. Rescue o p e r a t i o n s were
immediately s t a r t e d .
A two-man s e a r c h p a r t y a r r i v e d a t t h e s i t e a t 1250 h. The l e a d e r , a
park warden, assessed t h e d e b r i s , determined t h e most l i k e l y l o c a t i o n of
b u r i a l and d i r e c t e d t h e 16-man follow-up p a r t y t o t h e bottom end of t h e
avalanche where probing was s t a r t e d i n t h r e e l i n e s . Guards were posted
and an escape r o u t e was planned owing t o t h e extreme avalanche hazard.
A t 1430 h t h e v i c t i m was l o c a t e d approximately 100 m from t h e t o e of
t h e avalanche, b u r i e d under 2 m of snow. A s soon a s h i s head was
uncovered mouth-to-mouth r e s u s c i t a t i o n was s t a r t e d and continued while
h i s body was uncovered. The v i c t i m was t r a n s p o r t e d by toboggan t o a
f i r s t - a i d s t a t i o n 400 m away where a doctor continued a r t i f i c i a l
r e s p i r a t i o n u n t i l 1550 h with no p o s i t i v e r e s u l t s . The v i c t i m was
determined t o have died by s u f f o c a t i o n .
AVALANCHE DATA
New snow on a weak b a s e of depth hoar was t h e cause of t h i s dry
s l a b avalanche, w i t h a f r a c t u r e 450 m wide. I t r e l e a s e d a t an a l t i t u d e
of approximately 2100 m on a 35 deg s l o p e w i t h an e a s t e r l y a s p e c t . The
moving snow was channelled and t h e avalanche d e p o s i t v a r i e d i n depth
from 3 t o 6 m.
COMMENT
The s l o p e where t h e avalanche occurred was o u t s i d e t h e s k i run, was
posted a s an avalanche a r e a , and known a s such t o l o c a l s k i e r s . I t had
been n e i t h e r s k i e d b e f o r e nor s t a b i l i z e d by o t h e r means. I t would
appear t h a t t h e v i c t i m could not r e s i s t t h e temptation of s k i i n g t h e new
snow on t h e undisturbed slope, and t h a t b y doing so he t r i g g e r e d t h e
avalanche.
Figure 8
Avalanche, Mount Norquay, 28 February 1965
a)
b)
Deposition zone and t r a c k o f avalanche
F r a c t u r e and bed s u r f a c e of avalanche
(Courtesy Parks Canada)
KOOTENAY PASS, CRESTON, B .C
.
28 DECEMBER 1965
One c a r b u r i e d and one person k i l l e d
WEATHER
Observations a t Kootenay Pass Summit, 1770 m ASL
Date
Tempera t u r e
OC
Max
Min
New Snow
cm
24 December
-4.5
-11
30.5
25 December
-5
-18.5
40.5
26 December
-6
-12.5
5
27 December
-3.5
-11
24
28December
-3.5
- 5.5
56
Heavy snowfall a t t h e Kootenay Pass on 24 December and on t h e
morning o f 25 December t a p e r e d o f f i n t o l i g h t i n t e r m i t t e n t snowfall w i t h
c o o l e r temperatures on t h e 26th. Heavy snowfall resumed on 27 December
and continued throughout t h e day, causing s e v e r a l avalanches t h a t reached
t h e road and r e q u i r e d s h o r t c l o s u r e s f o r clean-up.
ACCIDENT SUMMARY
About 0430 h, 28 December, t h e Kootenay Pass highway foreman was
n o t i f i e d by a snowplow o p e r a t o r t h a t an avalanche was blocking t h e highway 4 . 3 km e a s t o f t h e summit a t e l e v a t i o n 1500 m. The foreman proceeded
immediately t o t h e s c e n e and found t h a t s e v e r a l small dry avalanches had
combined t o cover t h e highway t o a depth o f about 2 m. Walking o v e r t h e
d e p o s i t e d snow from t h e west s i d e t h e foreman n o t e d a l i g h t coming from a
h o l e i n t h e snow and on c l o s e r i n v e s t i g a t i o n discovered a sedan c a r . The
c a r was covered by about 50 cm o f avalanche snow; a man was i n s i d e ,
slumped over t h e wheel.
RESCUE
A member of t h e highways crew e n t e r e d t h e c a r v i a t h e h o l e i n t h e
snow and t h e open passenger window t o attempt t o r o u s e t h e d r i v e r . He
was unable t o do s o ; no s i g n s o f l i f e were e v i d e n t and r i g o r m o r t i s had
s t a r t e d t o s e t i n . The f a n o f t h e c a r h e a t e r was blowing, t h e i g n i t i o n
s w i t c h t u r n e d on, b u t t h e engine was not running. The time was about
0445 h .
The RCMP and a d o c t o r were immediately c a l l e d t o t h e scene, w h i l e
highways personnel conducted a s e a r c h f o r a p o s s i b l e c a r passenger.
Although i t seemed probable t h a t t h e d r i v e r had opened t h e passenger
window and pushed a h o l e up through t h e snow, a companion could have done
t h i s and made h i s escape. The snow on t h e road was probed, b u t no f u r t h e r
v i c t i m s were found. The occupant of t h e c a r was o f f i c i a l l y pronounced
dead and removed from t h e scene a t 0800 h . Carbon-monoxide poisoning was
l a t e r determined a s t h e cause o f d e a t h .
AVALANCHE
S e v e r a l avalanches had s t a r t e d from d i f f e r e n t l o c a t i o n s on a l a r g e
open rock b l u f f 450 m above t h e road. The s t a r t i n g zone had an
approximate g r a d i e n t of 40 t o 45 deg, w i t h a s o u t h - e a s t a s p e c t . The
avalanches covered about 200 m o f t h e highway w i t h a n average depth o f
2 m. The avalanche d e p o s i t was l o o s e and d r y and d i d n o t damage t h e
automobile
.
COMMENT
The truck-plow had l e f t t h e summit on a n e a s t e r l y run a t about
0300 h , and d i d n o t meet any t r a f f i c . From t h e amount o f new snow on
t h e avalanche d e p o s i t it was probable t h a t t h e avalanches had run s h o r t l y
a f t e r t h e plow had p a s s e d . The v i c t i m , a l s o t r a v e l l i n g e a s t , must have
been caught s h o r t l y a f t e r 0300 h. He was unhurt, a p p a r e n t l y decided t o
w a i t f o r h e l p , and kept t h e engine running i n o r d e r t o keep warm.
The c a r was equipped w i t h h o t c o f f e e , food, and b l a n k e t s , i n d i c a t i n g
preparedness f o r w i n t e r d r i v i n g . Although a n a i r h o l e had been punched
through t h e avalanche snow, it was i n s u f f i c i e n t t o allow t h e heavy exhaust
gases t o escape, and t h e v i c t i m was overcome by carbon monoxide. I t may
b e concluded t h a t a most important measure when one i s i n a c a r and b u r i e d
i n snow i s t o t u r n o f f t h e engine immediately.
ROGERS PASS, B .C.
8 JANUARY 1966
%o workmen on road k i l l e d
WEATHER
Observations a t Rogers Pass, 1307 m ASL
Temperature
O
Date
Time
Max
c
Min
New Snow
Depth
cm
Water
Equivalent
mm
Tot a1
Snow
Depth
cm
Wind
km/ h
Recorded Average h o u r l y Wind on 8 January a t MacDonald, West Shoulder,
1930 m ASL
Time
Direction
Speed
km/ h
16
6.5
1.5
8
1.5
8
21
120
120
96
120
Note:
The maximum c a p a c i t y o f t h e r e c o r d e r
i s 120 h / h .
I t was e s t i m a t e d t h a t
t h e windspeed exceeded t h i s l e v e l by
a c o n s i d e r a b l e amount on t h e morning
o f 8 January.
Between 27 December and 8 January 166 cm o f new snow f e l l i n t h e
Rogers Pass a r e a a t low temperatures. These u n u s u a l l y low temperatures
caused t h e snowpack t o remain l o o s e and u n s e t t l e d .
The MacDonald West Shoulder a r e a was s t a b i l i z e d by a r t i l l e r y on
2 January, 6 January, and a g a i n a t 2000 h , 7 January. During t h e l a s t
shoot a n avalanche was observed t o come h a l f way down t h e a l l u v i a l fan
of p a t h No. 4. Rumbling was heard a s a r e s u l t o f a round f i r e d i n t o
p a t h No. 3, b u t no avalanche was observed owing t o l i m i t e d v i s i b i l i t y .
At0800 h on 8 January t h e windspeed changed from between 8 and 24
km/h t o speeds i n excess o f 120 km/h. An unprecedented accumulation of
wind- t r a n s p o r t e d snow i n t h e avalanche s t a r t i n g zones and i n c r e a s i n g
temperatures caused t h e hazard t o r i s e q u i c k l y . The Trans-Canada Highway was c l o s e d a t t h e g a t e s o f t h e National Park a t 0850 h .
ACCIDENT SUMMARY
A t 0900 h a n a t u r a l avalanche o c c u r r e d a t MacDonald West Shoulder,
p a t h No. 4, followed a t 0910 h by an avalanche i n p a t h No. 3 . Each
covered t h e highway f o r a l e n g t h g r e a t e r t h a n 100 m. The avalanche
hazard a n a l y s t c o n s i d e r e d t h a t t r a f f i c t r a v e l l i n g i n s i d e t h e park g a t e s
would n o t have had time t o c l e a r t h e a r e a , and t h a t someone could have
been caught i n t h e avalanches, p a r t i c u l a r l y i n p a t h No. 3 . Because t h e
u n s t a b l e snow had been removed from t h e s t a r t i n g zones o f p a t h s No. 3 and
4 t h e a r e a below was r e a s o n a b l y s a f e , and a probing p a r t y was o r g a n i z e d
and d i s p a t c h e d t o p a t h No. 3 a t 0920 h. A l l personnel were warned o f t h e
extreme hazard from t h e a d j a c e n t p a t h s No. 1 and 2, a s well a s from t h e
Cheops p a t h No. 2 a c r o s s t h e v a l l e y . An avalanche look-out was p o s t e d .
A f r o n t - e n d l o a d e r and a D-6 b u l l d o z e r began t o remove t h e d e p o s i t e d
snow from p a t h No. 3 . The o p e r a t o r s were made aware of t h e extreme
danger from f u r t h e r s l i d e s , b u t t h e y continued t o work. A t 1053 h a
r e l e a s e was observed i n t h e b a s i n above p a t h No. 2 and a warning c a l l
given. The probe team immediately r a n t o s a f e t y , b u t t h e machine
o p e r a t o r s could n o t r e a c t s o q u i c k l y and were caught when t h e avalanche
h i t t h e road and lapped over t h e avalanche d e p o s i t i n path No. 3 .
RESCUE
The probe team on s i t e s t a r t e d a n immediate s e a r c h f o r t h e o p e r a t o r s .
The l o a d e r had been c a r r i e d t o t h e edge o f t h e road and turned o v e r , one
wheel j u s t showing above t h e snow; t h e b u l l d o z e r was completely b u r i e d .
A f t e r about 2 i h t h e l o a d e r o p e r a t o r was recovered, dead. The body was
removed and t h e s e a r c h continued f o r t h e o t h e r o p e r a t o r .
Snow and high winds continued and by 1450 h r e g e n e r a t i o n i n t h e
r e l e a s e a r e a s c r e a t e d such a hazard t h a t t h e r e s c u e teams were withdrawn.
Because t h e avalanche blocked a c c e s s t o t h e f i r i n g p o s i t i o n s , t h e gun had
t o b e dragged a c r o s s t h e d e p o s i t s . S t a b i l i z a t i o n by a r t i l l e r y was, t h e r e f o r e , a slow and dangerous p r o c e s s . By 1825 h g u n f i r e had been used, and
t h e a r e a was considered s a f e . e n o u g h t o allow r e s c u e o p e r a t i o n s t o b e
resumed. The t r a c t o r o p e r a t o r ' s body was recovered a t 1945 h . H i s
machine was s t i l l u p r i g h t , b u t was 30 m o f f t h e r o a d .
With t h e ongoing storm t h e hazard remained extreme and o p e r a t i o n s
were c l o s e d down f o r t h e n i g h t . Shooting began t h e f o l l o w i n g morning and
t h e highway was opened i n t h e evening.
AVALANCHE
Unconsolidated deep snow, extremely s t r o n g wind, and a r i s i n g
temperature were t h e f a c t o r s t h a t caused t h e d r y s l a b avalanche, which
s t a r t e d a t an e l e v a t i o n o f 2700 m and r a n t o t h e highway a t 1310 m . The
snow i n p a t h s No. 1 and 2 f r a c t u r e d simultaneously o v e r a t o t a l width of
450 m and a depth o f between 1 and 5 m. The avalanche covered 300 m of
t h e highway and 20 m o f t h e p r e v i o u s l y d e p o s i t e d snow i n p a t h No. 3.
Trees 50 t o 60 y e a r s o l d between p a t h s No. 2 and 3 were t o r n o u t .
Records o f avalanche occurrences a t Rogers Pass s i n c e 1953 do n o t
l i s t a n avalanche o f s i m i l a r s i z e a t t h i s s i t e , although s m a l l e r
avalanches have reached t h e highway on t h e average o f once i n two y e a r s .
The avalanche c o n t r o l s t a f f on t h e s p o t e s t i m a t e d 1i min a s t h e time
between t h e s t a r t o f t h e avalanche and i t s a r r i v a l a t t h e highway. This
would correspond t o an average speed o f 100 km/h. The average i n c l i n e o f
t h e avalanche t r a c k i s 31 deg.
COMMENTS
The a c c i d e n t i s a reminder o f t h e h a z a r d o f f u r t h e r avalanches,
p a r t i c u l a r l y i n a d j a c e n t p a t h s , when a n avalanche has covered a road.
The p o s s i b i l i t y o f a d d i t i o n a l avalanches must always b e considered b e f o r e
snow removal o p e r a t i o n s a r e c a r r i e d o u t . A d d i t i o n a l avalanches can
endanger n o t o n l y t h e maintenance s t a f f b u t a l s o t r a f f i c t h a t i s sometimes stopped i n f r o n t o f avalanche d e p o s i t s .
MOUNT WH ITEHORN, LAKE LOUISE, ALBERTA
30 JANUARY 1967
One s k i e r k i l l e d , one i n j u r e d
WEATHER
Observations a t Lake Louise Townsite, 1530 m ASL
Temperature
O
Date
c
Max
M in
Snowfall
cm
26Jan
-5.5
-20.5
27Jan
-3
-
28 J a n
1
- 8.5
10
29 J a n
1.5
-12.2
T
30 J a n
1
- 10
9.5
T o t a l Snow Depth
cm
96.5
7.5
10
101.5
109
106.5
117
The avalanche hazard was considered t o b e high owing t o wind, which had
produced a s l a b c o n d i t i o n above t h e t r e e l i n e , and t o high temperatures i n
t h e afternoon..
ACCIDENT SUMMARY
A group of t h r e e s k i e r s , a mountain guide, a s k i patrolman, and
another l o c a l r e s i d e n t , l e f t t h e t o p of Eagle C h a i r t o s k i t h e powder snow
a t t h e Ptarmigan Ridge. The group t r a v e r s e d a s l o p e marked w i t h s i g n s
'Avalanche A r e a t by following t h e t r a c k s o f many o t h e r s who had d e f i e d
t h e warning.
The l e a d s k i e r t e s t e d a s h o r t s t e e p s l o p e w i t h no r e s u l t s , then a l l
t h r e e continued t h e t r a v e r s e i n t o t h e a r e a of t h e Ptarmigan Chutes,
p a s s i n g o l d t r a c k s made during t h e previous weekend. The second chute
was chosen f o r downhill s k i i n g .
The patrolman l e d o f f , s k i e d about 50 m downslope, t h e n stopped.
The guide passed him and continued down a n o t h e r 100 m. The t h i r d s k i e r
t h e n s t a r t e d down and t h e patrolman recommenced h i s run, stopping a g a i n
by some small t r e e s where h e t u r n e d t o s e e an avalanche coming down t h e
c h u t e . The t h i r d s k i e r shouted a warning, b u t both t h e patrolman and
t h e guide were caught by t h e fast-moving snow. The patrolman grabbed a
t r e e , b u t i t broke under t h e impact o f t h e avalanche and he was c a r r i e d
f u r t h e r down w i t h t h e snow. He saw h i s companion being f l i p p e d i n t o t h e
a i r b e s i d e him. A second wave o f snow engulfed t h e patrolman, b u t he was
a b l e t o s t a y on t o p by swimming and was f r e e when t h e s l i d e came t o r e s t ,
s u f f e r i n g o n l y a n i n j u r e d shoulder. The t h i r d s k i e r had escaped t h e
avalanche, b u t t h e g u i d e was nowhere t o b e s e e n . The time of t h e a c c i d e n t
was 1435 h.
RESCUE
Another s k i e r who happened t o b e n e a r t h e a c c i d e n t s i t e immediately
s k i e d o u t f o r help. He shouted t o t h o s e on t h e c h a i r l i f t , and they i n
t u r n a l e r t e d t h e s k i p a t r o l a t 1440 h . The p a t r o l immediately c o n t a c t e d
t h e p a r k warden i n t h e a r e a and organized a s e a r c h p a r t y . The f i r s t
r e s c u e group a r r i v e d on t h e s i t e a t 1500 h, marked t h e l a s t - s e e n p o i n t ,
and s e t up probe l i n e s . Some were d i r e c t e d t o s e a r c h o t h e r l i k e l y
b u r i a l s p o t s , and when a d d i t i o n a l equipment a r r i v e d from Temple Lodge,
t h e probe l i n e s were extended.
The guide was d i s c o v e r e d a t 1520 h l y i n g f a c e down under 1 m o f snow
a t t h e b a s e o f a l a r g e t r e e by one of t h e p r o b e r s who s e a r c h e d l i k e l y
b u r i a l s p o t s . By 1525 h h e was f r e e d from t h e snow and cardiopulmonary
r e s u s c i t a t i o n was commenced by a d o c t o r i n t h e r e s c u e group. CPR was
continued u n t i l 1605 h when t h e d o c t o r d e c l a r e d t h a t t h e v i c t i m would n o t
recover.
AVALANCHE
The avalanche was caused by r e c e n t snowfall and wind. Avalanches
had been r e l e a s e d by e x p l o s i v e s i n t h i s a r e a e a r l i e r i n t h e w i n t e r . I t
was a d r y s l a b avalanche w i t h a high-speed flowing motion and a powder
component. I t s p a t h h a s a s o u t h e a s t a s p e c t i n t h e l e e o f t h e p r e v a i l i n g
wind, t h e t o p o f t h e s l o p e a c l i f f t h a t i s u s u a l l y overhung by c o r n i c e s .
The avalanche f r a c t u r e d a t t h e s l o p e t r a n s i t i o n below t h e c l i f f where t h e
i n c l i n a t i o n i s about 40 deg. The avalanche d e p o s i t was 250 m long and
60 m wide, w i t h a maximum depth o f 3.5 m.
COMMENT
I t i s h a r d t o understand why experienced mountaineers, who knew t h e
avalanche p a t h s o f t h e a r e a and had had a n o p p o r t u n i t y t o observe
continuously t h e weather and t h e snow c o n d i t i o n s would i g n o r e t h e
avalanche hazard. The d e s i r e t o s k i s t e e p , u n d i s t u r b e d s l o p e s sometimes
appears t o b e s t r o n g e r t h a n t h e thought o f danger.
..
KOOTENAY PASS, CRESTON, B C
16 MARCH 1967
One c a r b u r i e d
WEATHER
Heavy snowfall on 15 March t a p e r e d o f f and continued t o b e l i g h t
through 16 March. Strong, g u s t y wind p r e v a i l e d throughout t h e n i g h t of
15 March and t h e n i g h t o f t h e 1 6 t h .
ACCIDENT SUMMARY
Late i n t h e evening o f 16 March two truck-plows were working on t h e
e a s t s i d e o f Kootenay Pass towards t h e summit. One c a r t r a v e l l e d between
them, and two l i g h t t r u c k s followed. Without warning an avalanche came
from t h e rock b l u f f s above t h e road, c a t c h i n g a l l f i v e v e h i c l e s . The
two truck-plows were p a r t l y b u r i e d , one w i t h o n l y t h e cab f l a s h e r showing.
The two v e h i c l e s f o l l o w i n g were l i g h t l y b u r i e d and t h e i r d r i v e r s were a b l e
t o g e t out, b u t t h e automobile between t h e plows had d i s a p p e a r e d .
RESCUE
Because t h e c a r had been t r a v e l l i n g between t h e plows i t was
q u i c k l y l o c a t e d . Digging down through about 2 m o f l o o s e snow t h e t r u c k
o p e r a t o r s found t h e r e a r c a r window open and t h e d r i v e r c o n s c i o u s ~ a n d
u n h u r t . The d r i v e r informed them t h a t h e was a l l r i g h t and would w a i t i n
t h e c a r u n t i l it was removed from t h e d e b r i s .
The plow d r i v e r s t h e n proceeded t o t h e summit and r e p o r t e d t o t h e
foreman who decided t h e d r i v e r should n o t have been allowed t o s t a y w i t h
h i s c a r . Rushing back t o t h e a c c i d e n t s i t e , t h e plow o p e r a t o r s dug down
t o f i n d t h e d r i v e r unconscious a t t h e wheel. One man went through t h e
open r e a r window w i t h a rope and t h e unconscious d r i v e r was hauled t o
t h e s u r f a c e . A l l symptoms i n d i c a t e d t h a t t h e man was s u f f e r i n g from CO
poisoning, b u t h e was s t i l l b r e a t h i n g weakly. A d o c t o r i n Creston, who
was c o n t a c t e d by r a d i o , i n s t r u c t e d t h e crew t o e x e r c i s e t h e limbs o f t h e
v i c t i m , and h e was slowly worked i n t o consciousness, then p l a c e d on a
toboggan, h a u l e d about 1 km over o t h e r avalanche d e p o s i t s and brought by
ambulance t o Creston where he recovered completely.
AVALANCHE
The avalanche, caused by snowfall and wind, o c c u r r e d on t h e e a s t s i d e
of Kootenay Pass where numerous avalanches o f t e n cover t h e highway o v e r
a l e n g t h o f about 1 km. On 16 March 1967 about one dozen avalanches
reached t h e highway i n t h a t a r e a and d e p o s i t e d snow up t o 4 . 5 m deep on
the inside lane.
COMMENT
The a c c i d e n t occurred a t t h e same l o c a t i o n and under circumstances
s i m i l a r t o t h o s e o f t h e a c c i d e n t on 28 December 1965 ( s e e Figure 9)
The d r i v e r , b u r i e d i n t h e snow, r a n h i s c a r engine f o r a s h o r t time t o
g a i n a b i t o f warmth b u t was soon overcome by carbon monoxide. He was
lucky t o b e saved by t h e quick a c t i o n o f t h e highway foreman.
.
PARKER RIDGE, BANFF NATIONAL PARK, ALBERTA
9 DECEMBER 1967
One s k i e r k i l l e d
WEATHER
New snow t o t a l l i n g about 30 cm f e l l i n t h e a r e a i n t h e f i r s t week o f
December. On
December t h e wind was southwest, t h e temperature -4.5"C,
and wind s l a b s had formed.
ACCIDENT SUMMARY
On 9 December a p a r t y o f f o u r young s k i e r s d e p a r t e d from t h e youth
h o s t e l t o h i k e and s k i on Parker Ridge. While r e t u r n i n g t o t h e h o s t e l
t h e p a r t y came a c r o s s a small s t e e p bowl f a c i n g n o r t h e a s t . The l e a d
s k i e r t r a v e r s e d t h e s l o p e from r i g h t t o l e f t . When a second s k i e r
followed h i s t r a c k , a s l a b broke above, s h e f e l l , and t h e s l a b s l i d o v e r
h e r . The time was approximately 1500 h .
RESCUE
'Ihe v i c t i m was l o c a t e d by h e r companions a t 1530 h, unconscious and
n o t b r e a t h i n g , b u r i e d under 30 cm o f snow i n a s i t t i n g p o s i t i o n .
A r t i f i c i a l r e s p i r a t i o n was c a r r i e d o u t f o r over a n hour w i t h no response.
A park warden, c a l l e d by a member o f t h e group, a r r i v e d on t h e s i t e w i t h
a toboggan a t 1720 h and took t h e body t o t h e highway f o r t r a n s p o r t a t i o n
t o Banff. S u f f o c a t i o n was l a t e r determined a s t h e cause o f d e a t h .
AVALANCHE
S o u t h w e s t e r l y wind from t h e Saskatchewan G l a c i e r was r e s p o n s i b l e
f o r t h e formation o f t h e avalanche. The windward, n o r t h e a s t s i d e of t h e
r i d g e above t h e avalanche s i t e was blown b a r e o f snow and deep snow had
accumulated on t h e l e e s i d e . The avalanche was a d r y s l a b t h a t f r a c t u r e d
with a depth o f 30 t o 100 cm and b a r e l y broke up d u r i n g i t s s h o r t run.
The i n c l i n a t i o n o f t h e s l o p e where t h e avalanche s t a r t e d i s 35 deg and
t h a t o f t h e surrounding t e r r a i n 20 t o 25 deg.
COMMENT
The a c c i d e n t i s a n example o f t h e hazard t o s k i e r s from even small
avalanches. A s t h i s c a s e demonstrates, t h e snow may f r a c t u r e n o t when
t h e f i r s t s k i e r c r o s s e s t h e s l o p e b u t w i t h t h e second o r l a t e r s k i e r s .
WIND
_
)(
(8)
-
L O C A T I O N O F SKIERS
L O C A T I O N O F BURIED V I C T I M
F I R S T S K I E R ' S TRACK
-"%
-"
&om
?E(
F i g u r e 10 S k e t c h o f a v a l a n c h e , P a r k e r Ridge, 9 December 1967
MOUNT HECTOR, LAKE LOUISE, ALBERTA
23 MARCH 1969
One s k i e r k i l l e d
WEATHER
Observations a t Bow Summit, 2050 m ASL
Date
Temperature
O c
New Snow
cm
18 March pm
19 March am
19 March pm
20 March am
-4.5
20 March pm
6.5
21 March am
-6.5
21 March pm
3.5
22 March am
0
22 March pm
2
23 March am
-1.5
23 March pm
6.5
On 23 March a t t h e a c c i d e n t s i t e t h e temperature was approximately
4°C and winds were calm
ACC IDENT SUMMARY
A p a r t y of one man and two women l e f t t h e Banff-Jasper highway a t
Hector Creek t o climb Mount Hector on s k i s . When t h e y met two o t h e r
s k i e r s on t h e way up, t h e f i v e proceeded t o g e t h e r t o t h e f o o t of t h e
Hector G l a c i e r . The i n i t i a l p a r t y of t h r e e , inexperienced mountaineers,
decided t o s t o p t h e r e while t h e o t h e r two, experienced mountaineers,
continued. The experienced s k i e r s advised t h e o t h e r s t o wait f o r t h e i r
r e t u r n b e f o r e descending t o t h e highway.
Disregarding t h e advice, t h e t h r e e decided t o r e t u r n t o t h e v a l l e y ,
but on t h e way t h e y d e v i a t e d from t h e i r climbing r o u t e and e n t e r e d an
a d j a c e n t bowl. Here t h e man i n t h e p a r t y s k i e d below a c o r n i c e a t t h e
t o p of t h e s l o p e , s t a r t i n g a l a r g e avalanche t h a t swept him down. The
time was approximately 1430 h .
RESCUE
The two women were s t a n d i n g i n a rocky a r e a a d j a c e n t t o t h e f r a c t u r e
l i n e when t h e avalanche r e l e a s e d , and t h e y observed t h e man b e i n g c a r r i e d
away. They were a f r a i d , however, t o go down t h e s l o p e t o i n v e s t i g a t e .
A f t e r completing t h e i r r u n on t h e g l a c i e r and n o t f i n d i n g t h e o t h e r
t h r e e , t h e two experienced s k i e r s followed t h e t r a c k s u n t i l they found
t h e two women. One of t h e men descended t h e s l o p e and l o c a t e d a s k i
s t i c k i n g o u t from under some l a r g e b l o c k s o f d e p o s i t i o n p a r t way down
t h e avalanche p a t h . Buried beneath about 1 m of snow, t h e v i c t i m was
unconscious and n o t b r e a t h i n g . The s k i e r attempted a r t i f i c i a l
r e s p i r a t i o n , b u t d i d n o t observe any s i g n of recovery.
One o f t h e group r e p o r t e d t h e a c c i d e n t t o t h e park wardens a t 1700 h,
and a h e l i c o p t e r , using s e a r c h l i g h t s , flew t o t h e s i t e a t approximately
2000 h and picked up t h e body.
AVALANCHE DATA
Unstable depth hoar had been observed a l l w i n t e r i n t h e a r e a and
t o g e t h e r w i t h d r i f t i n g snow may have caused t h e formation of t h e
avalanche, which was t r i g g e r e d by t h e s k i e r .
This was a d r y s l a b avalanche, which r e l e a s e d about 2740 m ASL on
a s l o p e w i t h a n o r t h e a s t a s p e c t and i n c l i n e of about 35 deg. The
p r e v a i l i n g wind i n t h e a r e a i s southwest.
COMMENT
I f t h e two p a r t i e s had n o t s p l i t up t h e a c c i d e n t would probably n o t
have happened. Owing t o i n e x p e r i e n c e t h e v i c t i m chose a dangerous s l o p e
on h i s downhill run, and because o f t h e i n e x p e r i e n c e of h i s two
companions h e was recovered t o o l a t e . An immediate s e a r c h by t h e two
w i t n e s s e s might have saved t h e l i f e of t h e s k i e r .
CORNICE
s
W SLOPE
PRINCIPAL DEPOSIT
OF AVALANCHE SNOW
O N B O T T O M O F BOWL
E
Figure 11 Sketch map o f avalanche a t Mount Hector, 23 March 1969
DECEPTION PASS, LAKE LOUISE, ALBERTA
24 JANUARY 1970
One s k i e r b u r i e d
I
WEATHER
Observations a t Whitehorn Study P l o t , 1720 m ASL
-Temperature
O
Date
New Snow
Snow Depth
cm
cm
3
51
8
- 11
T
T
50
49
c
Max
Min
-
20Janam
-6
Pm
21Janam
0
-1.5
pm
-3.5
-10
T
49
22Janam
-4
4
53
Pm
23 J a n am
0
-2
-
4
51
55
Pm
24 Jan am
0
0
5.5
-13
-4.5
-12.5
pm
9.5
5.5
5
6
-
T
55
53
53
Winds were calm and t h e sky cloudy i n t h e Deception Pass a r e a on
24 January.
ACC IDENT SUMMARY
l h o s k i e r s l e f t Temple Lodge t o s k i t o Skoki Lodge v i a Boulder and
Deception P a s s e s . Both had some s k i mountaineering experience and were
equipped f o r an o v e r n i g h t t o u r . A t 1600 h, w h i l e t h e y were t r a v e r s i n g a
s t e e p s i d e h i l l southwest o f Deception Pass, an avalanche r e l e a s e d and
caught b o t h o f them.
RESCUE
When t h e avalanche came t o r e s t one s k i e r was a b l e t o f r e e h i m s e l f ,
but he could n o t l o c a t e h i s companion. He t h e r e f o r e s k i e d back t o r e p o r t
t h e a c c i d e n t a t Temple Lodge a t 1715 h. The f i r s t s e a r c h p a r t y organized
by National Park wardens l e f t a t 1730 h, a r r i v i n g a t t h e s i t e a t 1800 h .
Probing was organized immediately, and t h e v i c t i m was l o c a t e d a t 1830 h
b u r i e d under 1.2 m of snow. He was l y i n g on h i s s i d e , unconscious.
-44-
,
A r t i f i c i a l r e s p i r a t i o n was administered and t h e v i c t i m began t o
recover. S u f f e r i n g from extreme shock and oxygen d e f i c i e n c y he was
removed by motorized toboggan and t r a n s p o r t e d t o t h e h o s p i t a l i n Banff
where he recovered completely and was r e l e a s e d t h a t evening.
AVA LANCHE
The avalanche occurred a t approximately 2300 m ASL on a south-facing
s l o p e . This was a f u l l - d e p t h avalanche, f r a c t u r i n g through a depth of
1 t o 2 m. The d e p o s i t i o n was c o a r s e and chunky.
COMMENT
The two s k i e r s were t r a v e r s i n g a dangerous s l o p e and could have
picked a s a f e r r o u t e lower down t h e s l o p e . A s i s o f t e n t h e case,
choosing a s l i g h t l y slower, l e s s d i r e c t r o u t e i n s a f e t e r r a i n would have
been a wise move. The v i c t i m survived f o r an unusually long period.
S t a t i s t i c s of avalanche a c c i d e n t s show t h a t chance o f s u r v i v a l a f t e r
being b u r i e d f o r 2 h a r e only 10 p e r c e n t .
D E C E P T I O N PASS
__C
SKI TRACKS
4
DEEPEST D E P O S I
WITH LARGE CH
OF S L A B
70
(8)
)(
Figure 12
L O C A T I O N OF
rn
B U R I E D SKIER
L O C A T I O N O F O T H E R SKIER C A U G H T
Sketch o f avalanche a t Deception Pass, 24 January 1970
WESTCASTLE, P INCHER CREEK, ALBERTA
24 JANUARY 1970
One s k i e r k i l l e d
WEATHER
On 10 January approximately 1 m of snow had accumulated a t t h e
W e s t c a s t l e S k i Area. Temperatures d u r i n g t h e l a t t e r p a r t of December
were v e r y low, ranging down t o -30°c. The s k i p a t r o l noted t h a t depth
hoar had formed. On 21 January a temperature i n v e r s i o n was experienced,
w i t h temperatures o f -23°C recorded a t t h e b a s e and - 2 " ~a t t h e t o p of
t h e l i f t s 520 m h i g h e r . A t approximately 0930 h t h e s k i p a t r o l narrowly
escaped t h r e e medium-size n a t u r a l avalanches on t h e upper mountain.
Because o f t h e high hazard t h e l i f t s were c l o s e d , b u t no e x p l o s i v e
c o n t r o l was c a r r i e d o u t . High wind c o n d i t i o n s developed t h a t a f t e r n o o n .
The day o f t h e a c c i d e n t , 24 January, was a c l e a r day w i t h temperat u r e j u s t below f r e e z i n g and some good powder s k i i n g on l e e s l o p e s .
ACC I DENT SUMMARY
On 24 January a group o f t h r e e s k i e r s from Calgary came t o Westc a s t l e s e a r c h i n g f o r f r e s h powder snow. The p a r t y was observed s k i i n g
down l i f t l i n e s and.was advised by t h e s k i p a t r o l t o s k i on t h e main
runs o n l y and n o t i n t h e t r e e s because t h e snowpack was i n s u f f i c i e n t t o
c o v e r stumps and r o o t s .
A t approximately 1500 h t h e t h r e e s k i e r s e n t e r e d t h e t o p o f an a r e a
known a s Shotgun Gulch and began t o s k i down t o g e t h e r i n t h e powder snow.
Suddenly an avalanche r e l e a s e d above them. Two o f t h e s k i e r s were n e a r
t h e s i d e s o f t h e gulch and a b l e t o s k i c l e a r of t h e avalanche, b u t t h e
t h i r d was swept down by t h e f a s t moving snow.
RESCUE
When t h e avalanche stopped it was e v i d e n t t h a t t h e t h i r d s k i e r was
b u r i e d i n t h e avalanche d e p o s i t . One o f t h e w i t n e s s e s s k i e d down f o r
h e l p w h i l e t h e o t h e r began a s u r f a c e s e a r c h f o r c l u e s t o t h e v i c t i m ' s
l o c a t i o n . Approximately 10 min a f t e r t h e a c c i d e n t , t h e s k i p a t r o l was
n o t i f i e d and a r e s c u e immediately o r g a n i z e d . Probes t h a t were s t o r e d a t
t h e t o p o f t h e l i f t were picked up and s h o v e l s were c o l l e c t e d i n t h e
b a s e a r e a . The o p e r a t o r a t t h e t o p of t h e l i f t was i n s t r u c t e d by r a d i o
t o g a t h e r a l l patrolmen r i d i n g t h e l i f t . Twenty-five minutes a f t e r t h e
a c c i d e n t a r e s c u e p a r t y l e f t t h e upper l i f t t e r m i n a l .
Upon a r r i v i n g a t t h e scene r e s c u e r s found t h a t t h e w i t n e s s on t h e
s i t e had l o c a t e d a s k i p o l e and glove about one t h i r d o f t h e way down
t h e d e p o s i t e d snow and a toque about two t h i r d s o f t h e way down. A probe
l i n e was s e t up n e a r t h e toque and probing began u p h i l l . A second team
probing a t t h e t o e o f t h e d e p o s i t l o c a t e d t h e v i c t i m approximately 15 m
u p h i l l from t h e t o e o f t h e avalanche d e p o s i t , approximately 1 m below t h e
s u r f a c e . The time was n o t e s t a b l i s h e d . I t was immediately e v i d e n t t h a t
t h e v i c t i m had s u s t a i n e d s e v e r e m u l t i p l e i n j u r i e s and was e x h i b i t i n g no
s i g n s of l i f e . Doctors a t t h e s i t e d e c l a r e d t h e v i c t i m dead, and l a t e r
examination i n d i c a t e d t h a t t h e cause o f d e a t h was s e v e r e head i n j u r i e s .
AVALANCHE DATA
The dry s l a b avalanche f r a c t u r e d o v e r a width o f 15 m and a depth of
2.5 m on a b a s e o f depth hoar. The t r i g g e r was probably t h e combined
weight o f t h e t h r e e s k i e r s . The avalanche r a n a d i s t a n c e o f approximately
400 m and t h e d e p o s i t i o n was chunky and hard i n t e x t u r e .
COMMENT
An avalanche warning s i g n had been p l a c e d on a t r e e a t t h e t o p of
Shotgun Gulch i n 1968. I t was checked i n 1969, b u t no check was made a t
t h e beginning o f t h e 1969-70 season. On 25 January t h e s i g n was missing.
A f t e r t h e a c c i d e n t t h e a r e a was roped o f f and has been opened and c l o s e d
intermittently since then.
Control w i t h e x p l o s i v e s , c a r r i e d o u t a t t h e p r o p e r time, could have
prevented t h i s a c c i d e n t .
ACKNOWLEDGEMENT
The information on t h i s a c c i d e n t was c o l l e c t e d by R . Wilson-Smith.
A V A L A N C H E 51
P L A C E D I N 196
M A I N SKI
LAST-SEEN P O I N T
I
PART O F A S K I
POLE A N D
GLOVE FOUND
P
m
I
SKI POLE A N D G L O V E
LOCATION OF
BURIED V I C T I M
F i g u r e 1 3 Sketch of Shotgun Gulch, W e s t c a s t l e ,
A l b e r t a , 24 January 1970
Figure 14
Avalanche d e p o s i t i o n
a r e a , 24 January 1970
DECEPTION BAY, UNGAVA PENINSULA, QUEBEC
6-7 J U N E 1970
Tank farm damaged and o i l s p i l l e d
High temperatures were observed from 3 June t o t h e e a r l y hours o f
7 J u n e . Wind v e l o c i t i e s i n c r e a s e d t o 100 km/h, w i t h g u s t s t o 140 km/h i n
t h e e a r l y hours o f 6 June. I n a d d i t i o n , on 6 June t h e wind d i r e c t i o n
changed t o n o r t h - n o r t h e a s t , almost p a r a l l e l t o t h e g u l l y i n q u e s t i o n .
ACCIDENT
The tank farm i s l o c a t e d on Deception Bay ( a t t h e n o r t h e r n t i p o f
Ungava, west o f Sugluk) about 5 km from a camp o p e r a t e d by t h e owners o f
t h e tank farm. A t t h e time o f t h e a c c i d e n t t h e e n t i r e bay was covered
with i c e .
A s t h e tank farm i s n o t v i s i b l e from t h e camp, t h e r e were no eye
w i t n e s s e s o f t h e avalanche. The tank farm was l a s t seen i n t a c t on 5 J u n e .
I n u i t people p a s s i n g it on 8 June found it d e s t r o y e d and r e p o r t e d t h e
f a c t t o t h e camp. The avalanche had s t r u c k t h e t a n k s on a broad f r o n t
and run o u t on t h e s e a i c e . Four o f s i x t a n k s were d e s t r o y e d and one
damaged, c a u s i n g a s p i l l o f 427,000 g a l l o n s o f a r c t i c d i e s e l o i l and
gas01 i n e .
Damage t o t h e tank farm, replacement c o s t , l o s s o f o i l and g a s o l i n e
was e s t i m a t e d a t $523,000. D e t a i l s o f t h e damage caused by t h e o i l have
been r e p o r t e d [Ramseier e t a l . , 1973).
AVALANCHE
The avalanche was a s l u s h flow caused by r a p i d melting and f a i l u r e
o f t h e w a t e r - s a t u r a t e d snowpack. High a i r temperatures i n a s s o c i a t i o n
w i t h s t r o n g winds were r e s p o n s i b l e f o r t h e r a p i d r a t e o f snow m e l t i n g .
I t had a flow depth
The average depth o f t h e avalanche f r a c t u r e was 3 m.
of about 8 m i n t h e g u l l y and d e p o s i t e d snow 2 m deep a t t h e o i l t a n k s .
The s t a r t i n g zone was a t an a l t i t u d e o f 145 m and t h e tank farm a t
20 m. The p r o f i l e shows a n i n c l i n a t i o n o f t h e avalanche t r a c k between
6 and 17 deg.
COMMENT
Slush avalanches a r e common i n t h e A r c t i c h u t have a l s o been
observed i n a l p i n e a r e a s . They a r e u s u a l l y caused by r a p i d melting,
which produces more w a t e r t h a n can b e d r a i n e d a t t h e bottom o f t h e snowpack. A t Deception Bay t h e meltwater produced by h i g h a i r temperature
probably accumulated on a f r o z e n stream i n t h e g u l l y .
Remarkable i s t h e g e n t l e t e r r a i n t h a t spawned t h i s avalanche. I t
shows c l e a r l y t h a t s l u s h avalanches can occur on t e r r a i n f a r l e s s s e v e r e
i n s l o p e t h a n t h a t recorded f o r o t h e r t y p e s o f avalanche. A g u l l y
channelled t h e moving s l u s h , producing h i g h speed and g r e a t d e s t r u c t i v e
f o r c e . The p o s s i b i l i t y o f s l u s h avalanches must b e considered i n t h e
selection of s i t e s for structures i n the Arctic.
REFERENCE
Ramseier, R.O., G.S. Gantcheff, and L . Colby, 1973. O i l S p i l l a t
Deception Bay, Hudson S t r a i t . Environment Canada, Inland Water
D i r e c t o r a t e , Water Resources Branch, Ottawa, S c i e n t i f i c S e r i e s No. 29.
TANKS NOT DESTROYED
F i g u r e 15
0
\
S k e t c h o f a v a l a n c h e , Deception Bay,
Ungava P e n i n s u l a , Quebec, 6-7 June
1970. (Ramseier e t a l , 1973)
200
400
600
800
1000
D I S T A N C E FROM SHORE, rn
F i g u r e 16
P r o f i l e o f a v a l a n c h e t r a c k , Deception Bay, 6-7 J u n e 1970
RUTH-VERMONT MINE, PURCELL MOUNTAINS, GOLDEN,' B . C .
7 DECEMBER 1970
Mine powerhouse damaged
WEATHER
Observations a t t h e Mine S i t e . 1670 m ASL
Temperature
"C
Max
Min
Date
New Snow
cm
3 Dec
-
4Dec
-12
-14
4.1
5 Dec
-
4.5
- 19
27.4
6 Dec
-
1
- 14
46.2
7Dec
-0.5
-
19.3
1 Dec
2 Dec
7
-
9.5
11.7
7
-10.5
11.7
8
9.5
18.3
5.5
ACCIDENT SUMMARY
S e v e r a l avalanche p a t h s surround t h e mining camp ( s e e a l s o
16 January 1974). On 7 December an avalanche r a n from t h e Ruth S l i d e
a r e a s o u t h e a s t o f t h e mine and s t r u c k t h e mine powerhouse, d e s t r o y i n g
t h e w a l l s and roof and damaging machinery.
AVALANCHE DATA
T h i s was a n a t u r a l s o f t - s l a b avalanche t h a t r e l e a s e d a t a n a l t i t u d e
o f 2000 m and f e l l 430 m t o t h e powerhouse. The avalanche p a t h has a n
average s l o p e o f 42 deg and a n o r t h a s p e c t . The powerhouse was l o c a t e d
i n t h e run-out zone o f t h e avalanche a t t h e t o e o f t h e s l o p e .
COMMENT
The mine could n o t b e o p e r a t e d f o r s i x weeks following t h e avalanche.
Avalanches o c c u r f r e q u e n t l y i n t h i s a r e a every w i n t e r , b u t t h e y a r e n o t
u s u a l l y l a r g e enough t o damage t h e b u i l d i n g s . More s e v e r e damage was
caused on 16 January 1974.
,
+
POSS lBLl
STARTIN(
ZONES
L' .I' :> L
Figure 17
$*
tP
:.
Ruth-Vermont Mine, showing Ruth ( l e f t ) and Sheba
( r i g h t ) avalanche p a t h s ; t h e powerhouse i s t h e
uppermost b u i l d i n g .
An a v a l a n c h e - c a t c h i n g
b a r r i e r was l a t e r b u i l t .
..
GRANITE MOUNTAIN, ROSSLAND, B C
23 DECEMBER 1971
One s k i e r k i l l e d
WEATHER
Observations a t Rossland-MacLean S t a t i o n . 1082 m ASL
Date
Temperature
OC
Max
M in
Precipitation
mm
19 Dec
-5.5
-9.5
2.5
20 Dec
-2
-6.5
10.2
21 Dec
-0.5
-6.5
10.2
22 Dec
2
-2
12.7
23 Dec
0
-3
6.6
About 30 cm o f new snow f e l l on G r a n i t e Mountain i n t h e 24 h p r i o r
t o 1300 h , 23 December, and a warming t r e n d was noted from t h e e a r l y
morning hours t o mid-afternoon. Overcast c o n d i t i o n s and i n t e r m i t t e n t
snow p r e v a i l e d throughout t h e a f t e r n o o n .
ACCIDENT SUMMARY
A t about 1315 h on 23 December a group of f i v e experienced powder
s k i e r s e n t e r e d t h e Squaw Basin o f G r a n i t e Mountain. Numerous c h u t e s and
g l a d e s f a l l from Buffalo Ridge through Squaw Basin i n t o a t r a v e r s e t h a t
l e a d s back t o t h e r e g u l a r s k i r u n s .
The s k i e r s e n t e r e d an open, s l a b - l i k e s l o p e n e a r t h e t o p of Squaw
Basin and proceeded t o s k i down. A s t h e l a s t s k i e r s t a r t e d h i s f i r s t
t u r n , t h e s l o p e f r a c t u r e d around him and a small f a s t - f l o w i n g avalanche
c a r r i e d him down. The r e s t o f t h e p a r t y were n e a r a t r e e d a r e a lower
down t h e s l o p e and saw t h e i r companion caught by t h e moving snow, b u t
t h e y were unable t o l o c a t e him when t h e avalanche stopped. I t had moved
through a s p a r s e l y t r e e d a r e a , had p i l e d up snow a t s e v e r a l l o c a t i o n s ,
and stopped below t h e w i t n e s s e s . One s k i e r immediately d e p a r t e d f o r t h e
b a s e lodge t o r e p o r t t h e a c c i d e n t t o t h e s k i p a t r o l . The time was about
1345 h .
RESCUE
The t h r e e remaining s k i e r s d i v i d e d t h e d e p o s i t i o n a r e a i n t o s e c t i o n s
and proceeded t o comb i t f o r c l u e s . One member climbed t o check t h e
s l o p e above, b u t it was presumed t h a t t h e v i c t i m had been c a r r i e d w i t h
t h e main mass o f snow through t h e t r e e s t o t h e s l o p e below.
Meanwhile, t h e messenger reached t h e s k i p a t r o l a t t h e bottom o f
G r a n i t e Mountain a t about 1400 h. Volunteers were e n l i s t e d and a search
p a r t y equipped w i t h probes and shovels was d i s p a t c h e d immediately,
a r r i v i n g a t t h e s c e n e o f t h e a c c i d e n t a t 1440 h. Two probe l i n e s were
e s t a b l i s h e d , one on t h e h i g h e r open s l o p e and one on t h e lower s l o p e ,
w i t h a few i n d i v i d u a l s a s s i g n e d t o a random s e a r c h o f t h e t r e e d a r e a s .
A t 1510 h t h e v i c t i m ' s lower a n was d i s c o v e r e d p r o t r u d i n g from t h e
snow a t t h e b a s e o f a t r e e about 30 m below where he had been caught.
Digging down, t h e patrolmen discovered t h e v i c t i m b e n t u n n a t u r a l l y backwards a g a i n s t t h e t r e e and l i g h t l y b u r i e d . He was immediately removed
from t h e snow, cardiopulmonary r e s u s c i t a t i o n was administered, b u t no
s i g n s of l i f e r e t u r n e d . The body was removed by toboggan and a r r i v e d
a t t h e base p a t r o l room a t 1610 h.
The cause o f d e a t h was determined t o b e s u f f o c a t i o n , b u t s p i n a l
i n j u r i e s had been s u s t a i n e d i n t h e s l i d e . Witnesses thought t h a t t h e man
would have been a b l e t o r a i s e himself from t h e avalanche snow i f h e had
been conscious when h e came t o r e s t a g a i n s t t h e t r e e .
AVALANCHE
The avalanche was a s o f t s l a b , d r y and unconfined, w i t h a depth of
f r a c t u r e o f about 80 cm i n r e c e n t snow l a y e r s . The s t a r t i n g zone i s
about 1900 m above s e a l e v e l , f a c e s n o r t h , has a ground s u r f a c e of smooth
g r a n i t e s l a b and a s l o p e g r a d i e n t o f about 35 deg. The avalanche d e p o s i t
was of f a i r l y uniform c o n s i s t e n c y and had p i l e d up around t r e e s t o a
maximum depth o f 1.4 m
.
COMMENT
The avalanche was probably t r i g g e r e d by t h e s k i e r , who was t h e l a s t
of t h e f i v e down t h e s l o p e . I t i s o f t e n b e l i e v e d t h a t a s l o p e i s s t a b l e
if t h e f i r s t one o r two s k i e r s p a s s s a f e l y , b u t a s t h e example
i l l u s t r a t e s t h i s i s a n i n c o r r e c t and dangerous assumption. Many times,
e s p e c i a l l y w i t h deep s l a b i n s t a b i l i t y , o n l y t h e combined weight of
s e v e r a l p e r s o n s may i n i t i a t e a n avalanche o r t h e f a i l u r e p r o c e s s may b e
delayed.
The c a s e i l l u s t r a t e s t h a t avalanche v i c t i m s a r e sometimes found i n
snow t h a t has stopped a t t r e e s i n t h e avalanche path ( s e e a l s o 28 A p r i l
1963). Trees, t h e r e f o r e , a r e l i k e l y s p o t s o f b u r i a l and must b e checked
during t h e f i r s t , h a s t y s e a r c h .
The a c c i d e n t took p l a c e away from t h e r e g u l a r s k i runs, i n a known
and marked avalanche a r e a although t h e s l o p e s a r e always h e a v i l y t r a c k e d
following f r e s h s n o w f a l l s . Such hazards e x i s t i n many s k i developments
and education o f t h e s k i i n g p u b l i c i s probably t h e b e s t way t o p r e v e n t
accidents.
12
rn
LAST-SEEN
FOUR
\
F i g u r e 18
DEEPEST DEPOSIT
Sketch o f a v a l a n c h e s i t e , G r a n i t e Mountain,
Rossland, B.C., 23 December 1971
24 DECEMBER 1971
FLATHEAD VALLEY, FERNIE, B.C.
Three people on road k i l l e d
WEATHER
Observations a t F e r n i e , 1030 m ASL
Temperature
OC
Date
20 Dec
Max
-1
Precipitation
Min
mm
- 5.5
30.2
- 10
10.2
-14.5
26.5
21 Dec
1.5
22 Dec
-9.5
23 Dec
1.5
-18
10.9
24 Dec
3
-14.5
18.8
The snowfall a t F e r n i e i s g e n e r a l l y g r e a t e r t h a n t h a t i n t h e
F l a t h e a d Valley. On 24 December it was snowing i n t h e F l a t h e a d Valley,
w i t h wind from t h e southwest. Observations made a f t e r t h e a c c i d e n t
r e v e a l e d t h a t t h e snowcover i n t h e a r e a c o n s i s t e d o f 20 cm of depth hoar,
80 cm of o l d hard snow, and 60 cm o f new snow on t h e s u r f a c e .
ACCIDENT SUMMARY
The a c c i d e n t was n o t observed. The v i c t i m s , employees o f a logging
company, were coming o u t from a bush camp i n t h e F l a t h e a d Valley f o r t h e
Christmas h o l i d a y .
I t i s assumed t h a t t h e men were making t h e i r way along t h e f o r e s t r y
road i n a pick-up t r u c k and small t r a c t o r when they encountered avalanche
d e p o s i t s on t h e road; t h a t t h e y i n v e s t i g a t e d t h e d e p o s i t on f o o t , and
t h a t a second avalanche must have s t r u c k and swept them from t h e r o a d .
When t h e men had n o t r e p o r t e d by Christmas Day, a p a r t y was s e n t t o
i n v e s t i g a t e . Behind a l a r g e avalanche d e p o s i t i t discovered t h e t r u c k
and b u l l d o z e r , b o t h w i t h i g n i t i o n s w i t c h e s "on1', although t h e v e h i c l e s
had run o u t o f f u e l . I t was concluded t h a t t h e men were probably b u r i e d
i n one o f t h e avalanches and s e a r c h o p e r a t i o n s under t h e d i r e c t i o n of t h e
RCMP were i n i t i a t e d .
RESCUE
A number o f l a r g e avalanches had crossed t h e road and fanned o u t
i n t o t h e v a l l e y and a c r o s s t h e r i v e r , l e a v i n g an e x t e n s i v e a r e a t o b e
searched. The s e a r c h e r s assumed t h a t t h e v i c t i m s had been swept from t h e
road, c a r r i e d down t h e 20 m embankment and b u r i e d on t h e f l a t s below,
although no c l u e s could b e found.
The f i r s t v i c t i m ' s body was recovered 29 December a t 1430 h, using
a b u l l d o z e r , and s y s t e m a t i c a l l y digging through t h e d e b r i s . On
3 January t h e o t h e r two b o d i e s were l o c a t e d , one u s i n g a b u l l d o z e r and
one by an RCMP s e a r c h dog which had a r r i v e d t h a t day. A l l t h r e e men
were b u r i e d under approximately 2 m o f snow and had d i e d from s u f f o c a t i o n .
AVALANCHE
The avalanche s t a r t e d a t an a l t i t u d e o f 1850 m and r a n o v e r 650 m
v e r t i c a l l y on a 23 deg g r a d i e n t . The avalanche t r a c k i n q u e s t i o n i s
about 80 m wide. D e t a i l s o f t h e t y p e o f avalanche a r e vague. I t seems
t o have been a dry s l a b t y p e t h a t f r a c t u r e d through t h e o l d snow l a y e r s
on a n e a s t e r n exposure. The d e b r i s , d e p o s i t e d t o a d e p t h of 3 m, was
q u i t e h a r d by t h e time t h e a c c i d e n t was d i s c o v e r e d .
COMMENT
The a c c i d e n t i s an example o f t h e danger o f walking o v e r avalanche
d e p o s i t s d u r i n g hazardous p e r i o d s . The c l o s e p o s i t i o n of t h e bodies
would i n d i c a t e t h a t t h e men were i n a group and caught by s u r p r i s e by a
fast-moving l a r g e avalanche.
The s e a r c h dog was n o t brought t o t h e s i t e u n t i l 11 days a f t e r t h e
avalanche o c c u r r e d . A s i n many o t h e r c a s e s , t h e dog proved t o b e t h e
s u p e r i o r s e a r c h method, f o r a f t e r o n l y a s h o r t t i m e h e found t h e dead
body l y i n g i n w a t e r under 2 m o f h a r d snow.
Figure 19
Avalanche, F l a t h e a d V a l l e y .
(Photo c o u r t e s y D. Marino)
View from v a l l e y bottom.
5 FEBRUARY 1972
HIGHLAND CREEK, SCARBOROUGH, ONTARIO
l b o tobogganers k i l l e d
WEATHER
Observations a t Toronto Highland Creek S t a t i o n
Date
Temperature
OC
Max
M in
Precipitation
mm
0.5
-13
- 6.5
7.6
3 Feb
1.5
- 3
2.2
4 Feb
-4.5
- 8
2.5
5 Feb
-7
-14
T
1 Feb
2 Feb
-1
t
On t h e a f t e r n o o n o f 5 February i t was snowing, w i t h winds blowing
from t h e northwest a t 10 km/h and temperature - 1 2 ' ~ .
ACCIDENT SUMMARY
Highland Creek forms a r a v i n e about 25 m i n depth n e a r t h e i n t e r s e c t i o n of Markham Road and Highway 401 i n Scarborough, a d j a c e n t t o a
r e s i d e n t i a l a r e a . Wind-drifted snow had formed a c o r n i c e on t h e n o r t h
edge of t h e r a v i n e .
A t 1530 h on 5 February two young g i r l s , r e s i d e n t s o f t h e a r e a , l e f t
t h e i r homes t o f i n d a s u i t a b l e p l a c e f o r tobogganing. I t appears t h a t
they were walking a l o n g t h e n o r t h edge o f t h e r a v i n e when t h e c o r n i c e
c o l l a p s e d beneath t h e i r weight. The c h i l d r e n dropped about 8 m and were
b u r i e d by t h e f a l l i n g snow a t t h e s t e e p s i d e o f t h e r a v i n e .
RESCUE
When t h e two g i r l s d i d n o t r e t u r n home f o r d i n n e r t h e p o l i c e were
very l a r g e p r o p o r t i o n s ,
a l e r t e d . A s e a r c h was i n s t i t u t e d t h a t grew t o
w i t h hundreds o f v o l u n t e e r s . Foul p l a y was f i r s t suspected and a n
avalanche would n a t u r a l l y n o t be a s e a r c h c o n s i d e r a t i o n i n Metropolitan
Toronto. A t 1730 h on 6 February, however, one s e a r c h e r noted a f r e s h
s l i d e on t h e n o r t h s i d e o f Highland Creek r a v i n e n e a r t h e r e s i d e n t i a l
a r e a . Digging down he found t h e body o f one g i r l under 1 m o f snow and
about 15 m from t h e t o p o f t h e r a v i n e ; s h o r t l y a f t e r w a r d s t h e o t h e r body
was d i s c o v e r e d 1 . 5 m u p h i l l under 0 . 5 m of snow.
AVALANCHE DATA
The c o r n i c e had formed a t an a l t i t u d e o f 170 m ASL, above a r a v i n e
25 m deep w i t h an average s l o p e o f 45 deg. About a 2 m l e n g t h o f c o r n i c e
broke o f f and t h e snow d e p o s i t i o n was a maximum o f 2 m deep. Whether o r
n o t any s l a b r e l e a s e was a s s o c i a t e d w i t h t h e c o r n i c e f a i l u r e i s unknown,
b u t t h e d e b r i s was d e s c r i b e d a s b e i n g Ifsnow a s b i g a s huge s t o n e s . "
COMMENT
This case, t o g e t h e r w i t h t h e Cap Sant6 case of 14 January 1976,
i l l u s t r a t e s t h e f a c t t h a t hazardous avalanches may occur n o t only i n h i g h
mountains b u t anywhere t h a t t e r r a i n and snow form t h e r i g h t combination.
19 FEBRUARY 1972
MOUNT EDITH CAVELL, JASPER NATIONAL PARK, ALBERTA
Three mountain climbers k i l l e d , one i n j u r e d
WEATHER
Observations a t Marmot Basin. 2067 m ASL
Date
Temperature
"C
Max
M in
New Snow
Snow Depth
Wind
cm
cm
km/h
2
129
25
13
142
80
15 Feb
-6
16 Feb
-6.5
- 14
- 9
17 Feb
-3
-13.5
T
140
30
18 Feb
-3
-15.5
1
137
13
19 Feb
-9
-10.5
1
136
30
20 Feb
0
-
9
143
25
8.5
The mean temperatures recorded a t Marmot Basin i n December 1971 were
a maximum o f - 1 2 . 6 " ~ and a minimum o f -21.3"C, w i t h a t o t a l snowfall o f
78 cm. I n January t h e mean maximum temperature was -13.2'C and t h e mean
minimum - 2 3 . 3 " ~ , w i t h a t o t a l snowfall o f 110 cm. The c o l d weather
produced a n unconsolidated snowpack ( s e e Figure 20).
ACCIDENT SUMMARY
A climbing p a r t y o f f o u r , a l l experienced c l i m b e r s , r e g i s t e r e d a t
0800 h on 19 February t o ascend t h e East Ridge o f Mount Edith Cavell,
planning t o r e t u r n on t h e 20th around noon. The p a r t y l e f t t h e j u n c t i o n
o f Highway 93A and t h e E d i t h C a v e l l Road about 0830 h, a r r i v i n g a t t h e
Tea House about 1115 h by means o f motor toboggans.
The group t h e n climbed a snow headwall t o t h e s a d d l e a t t h e bottom
of t h e E a s t Ridge, and proceeded up t h e s n o w - f i l l e d g u l l y t o t h e l e f t of
t h e s t a n d a r d E a s t Ridge r o u t e . Some time a f t e r 1700 h, near t h e t o p of
t h e g u l l y , t h e y decided t o d i g a snow cave and bivouac f o r t h e n i g h t .
The snow cave was almost f i n i s h e d when a c r a c k was heard and t h e roof
f e l l i n . The time was about 1830 h .
RESCUE
Climber No. 1, who had been i n t h e cave a t t h e time o f t h e s t a r t of
t h e avalanche, was swept down, and a f t e r s l i d i n g and f r e e f a l l i n g came t o
r e s t on t h e s a d d l e a t t h e bottom of t h e g u l l y . Although he was p a r t l y
b u r i e d and had a broken arm, h e was a b l e t o f r e e himself and began a
s e a r c h f o r h i s companions. One l a y n e a r by, h i s r i g h t s i d e b u r i e d .
Climber No. 1 was a b l e t o d i g away t h e snow and found t h a t h i s
companion's r i g h t l e g was s e v e r e l y i n j u r e d .
Climber No. 1 wrapped t h e
i n j u r e d man i n any l o o s e c l o t h i n g and s l e e p i n g bags h e could f i n d on t h e
s u r f a c e and continued h i s s e a r c h f o r t h e o t h e r two p a r t y members.
Finding o n l y s c a t t e r e d equipment and unable t o l o c a t e t h e o t h e r s ,
climber No. 1 l e f t t o seek h e l p a t approximately 2000 h.
Carrying a torch, a s k i p o l e and a p o t of honey, he made h i s way
down t h e headwall. A f t e r t r a v e l l i n g on f o o t a l l n i g h t and through t h e
morning of 20 February, he reached h i s c a r and drove about 7 km t o t h e
Cavell Warden S t a t i o n , a r r i v i n g about 1200 h.
Rescue was i n i t i a t e d immediately. A group of park wardens, an
RCMP o f f i c e r and equipment were g a t h e r e d a t the. j u n c t i o n of 93A and
E d i t h C a v e l l Roads a t 1315 h . One group was d i s p a t c h e d on f o o t w h i l e
t h e o t h e r s awaited t h e a r r i v a l o f a h e l i c o p t e r . A t 1430 h two wardens
were a i r - l i f t e d t o t h e s a d d l e . The i n j u r e d climber and an assortment o f
equipment were l o c a t e d almost immediately, l i g h t l y covered by new snow.
The climber, however, was dead by t h a t time. B l i z z a r d c o n d i t i o n s and
poor v i s i b i l i t y p r e v a i l e d .
A t about 1600 h t h e weather c l e a r e d enough f o r a dog and h a n d l e r
and t h r e e more men t o be flown i n . The body of climber No. 2 was flown
t o J a s p e r and a l l p e r s o n a l belongings were c l e a r e d from t h e avalanche t o
allow t h e dog t o b e g i n h i s s e a r c h a t about 1620 h . The dog l o c a t e d t h e
t h i r d c l i m b e r ' s body a t 1630 h, b u r i e d under 10 cm of h a r d avalanche
snow and 10 cm of new snow. The dog then l o c a t e d v a r i o u s p e r s o n a l
o b j e c t s and t h e l a s t body a t approximately 1745 h . The t h i r d v i c t i m was
b u r i e d f a i r l y deeply, however,his hand extended toward t h e s u r f a c e and
covered by about 10 cm of hard snow and 10 cm new. Evacuation of t h e
v i c t i m s and t h e s e a r c h p a r t y began a t approximately 1815 h and was
completed a t 2030 h.
AVALANCHE DATA
The avalanche probably f r a c t u r e d over t h e f u l l depth of t h e snow on
weak l a y e r s formed d u r i n g t h e c o l d weather i n December and January. Deep
d r i f t i n g snow had probably accumulated i n t h e g u l l y . I t s t a r t e d a t an
e l e v a t i o n o f approximately 2800 m and was probably t r i g g e r e d by t h e
c l i m b e r s when t h e y excavated t h e snow cave. The g u l l y f a c e s s o u t h - e a s t
and has an average g r a d i e n t of 40 deg. The d e p o s i t e d avalanche snow was
up t o 5 m deep, hard, and s c a t t e r e d w i t h rock c h i p s .
COMMENT
Snow-filled g u l l i e s must be t r a v e l l e d w i t h c a u t i o n d u r i n g t h e w i n t e r
because t h e y a r e n a t u r a l channels f o r avalanches; furthermore, t h e deep
snow i n them may h i d e weak l a y e r s , and i t s s t a b i l i t y can change r a p i d l y
w i t h t h e o n s e t of wind, f r e s h snowfall, o r high temperatures. For t h e s e
reasons a g u l l y appears t o b e t h e wrong p l a c e f o r a n i g h t ' s bivouac.
The c a s e demonstrates how long i t may t a k e an organized r e s c u e
p a r t y t o r e a c h t h e s i t e o f an avalanche a c c i d e n t i n t h e back country.
I n such c a s e s a r e s c u e a l i v e i s u s u a l l y p o s s i b l e o n l y by t h e e f f o r t s of
s u r v i v o r s . I t i s sad t h a t two o f t h e v i c t i m s a t Mount E d i t h Cave11 were
b u r i e d t o o deep and t h a t t h e avalanche was t o o l a r g e t o permit a
s u c c e s s f u l s e a r c h by one person.
TEMPERATURE, OC
-10
-5
RAM RESISTANCE,
Figure 20
0
kg
Snow p r o f i l e a t Marmot Basin,
19 February 1972
F i g u r e 21
East Ridge o f Mount E d i t h Cave11 showing
l o c a t i o n o f a v a l a n c h e , 19 February 1972
(Photo c o u r t e s y Parks Canada)
EAGLE MOUNTAIN, SUNSHINE AREA, BANFF, ALBERTA
1 MARCH 1972
Extensive p r o p e r t y damage
WEATHER
Observations a t Mount Norquay, Banff, 1700 m ASL
Temperature
OC
Max
Min
Date
New Snow
cm
Total
Snow Depth
cm
26 February am
- 13
-27
8
150
Pm
27 February am
- 8
-11
-14
- 13
1
149
12
156
Pm
28 February am
- 11
- 19
- 21
- 19
164
-27
14
47
201
- 24
5
201
Pm
29 February am
1 March
Pm
am
Pm
no r e a d i n g s taken
-21
4
- 27
8
- 11
-
-28
25
1
2 11
206
204
Snowfall and temperatures a t Mount Norquay a p p e a r t o be w e l l
c o r r e l a t e d w i t h t h o s e a t t h e Sunshine Road, i n c l u d i n g Eagle Mountain,
although t h e snowfall a t Eagle Mountain i s u s u a l l y g r e a t e r t h a n t h a t
observed a t Mount Norquay. The t o t a l snowfall d u r i n g t h e w i n t e r 1971-72
i n t h e Banff a r e a would b e observed o r exceeded on t h e average o n l y
once i n 70 y e a r s , and storms o f t h e magnitude o f t h a t o f 26-29 February
a r e unusual f o r t h e a r e a . R e s i d e n t s a t Sunshine V i l l a g e , 4 km from t h e
a c c i d e n t s i t e , d e s c r i b e d t h e storm a s o f d i s a s t r o u s p r o p o r t i o n s , w i t h
more than 100 cm o f new snow, h i g h winds, and extreme d r i f t i n g . The
b a s e o f t h e snowpack c o n s i s t e d o f a 35 cm deep-depth hoar l a y e r .
On 29 February h e l i c o p t e r bombing was c a r r i e d o u t a t t h e avalanche
p a t h s along t h e a c c e s s road t o Sunshine V i l l a g e . The e x p l o s i o n s
r e l e a s e d avalanches a t t h e s i t e s o f Bourgeau No. 2, 3, 4, and 5, and a l l
d e p o s i t e d snow on t h e road. Powder snow avalanches reached t h e road a t
Eagle No. 1 and Eagle No. 2. Owing t o t h e c o n t i n u i n g hazard t h e snow on
t h e road was n o t removed.
ACCIDENT SUMMARY
On 1 March e x p l o s i v e c o n t r o l by h e l i c o p t e r was a g a i n c a r r i e d o u t on
t h e Bourgeau and Eagle avalanche p a t h s ; 6.8 k i l o c a n n i s t e r charges were
used, b o t h s i n g l y and i n combination i n l a r g e m u l t i p l e c h a r g e s . A t
Bourgeau No. 7 t h e bombing r e l e a s e d a v e r y l a r g e avalanche t h a t broke
t r e e s , expanded i t s p a t h , and covered t h e road w i t h e x t e n s i v e d e b r i s .
Eagle No. 4 was then bombed and t h e ensuing avalanche engulfed t h e
Bourgeau parking l o t a t t h e v a l l e y bottom. I t d e s t r o y e d a kiosk
completely, brought down 1 km o f powerline, b u r i e d 30 parked c a r s ,
damaged two 500-gal o i l t a n k s , and destroyed 2 ha o f f o r e s t . Because
t h e road was c l o s e d no one was i n t h e a r e a .
AVALANCHE
The u n u s u a l l y deep accumulation o f snow, heavy snowfall, and a weak
b a s e of snowcover provided t h e c o n d i t i o n s f o r avalanches o f c a t a s t r o p h i c
p r o p o r t i o n s . The avalanche s t a r t e d a s a f u l l - d e p t h , d r y s l a b a t 2200 m
ASL and r a n t o t h e p a r k i n g l o t a t 1645 m ASL. The p a t h has an average
i n c l i n e of 30 deg and a northwest a s p e c t . The avalanche snow was up t o
5 m deep on t h e p a r k i n g l o t . No p r e v i o u s occurrence o f equal magnitude
had been observed a t t h i s l o c a t i o n , b u t t r e e growth l e a d s t o t h e
conclusion t h a t avalanches o f s i m i l a r s i z e o c c u r r e d about 50 y e a r s ago.
COMMENT
The d e s t r u c t i v e avalanche demonstrates t h a t weather can b e a s e r i o u s
c o n s t r a i n t t o t h e s u c c e s s f u l a p p l i c a t i o n o f h e l i c o p t e r bombing.
Avalanches should have been r e l e a s e d a r t i f i c i a l l y much e a r l i e r when t h e y
would have been small, b u t t h e c o n t i n u i n g snowstorm prevented f l y i n g i n
time. When c o n t r o l work was f i n a l l y c a r r i e d o u t , a l a r g e , unmanageable
avalanche had b u i l t up. Dropping e x p l o s i v e s from a h e l i c o p t e r h a s
proved t o b e a f a s t and inexpensive avalanche c o n t r o l method a t Banff
where a h e l i c o p t e r i s a v a i l a b l e a t a l l times c l o s e t o t h e avalanche
a r e a s , b u t t h e continuous o p e r a t i o n o f a road o r t h e s a f e t y of b u i l d i n g s
should n o t depend on t h i s method a l o n e .
Figure 22
Avalanche p a t h , Eagle No. 4, w i t h Bourgeau p a r k i n g a r e a a t t h e
bottom, Sunshine a r e a , Banff, A l b e r t a . (Photo Bruno Engler)
.
G IANT MASCOT MINE, HOPE, B C .
5 MARCH 1972
Three occupants o f a v e h i c l e k i l l e d
Observations a t Hope, Kawkawa Lake, 142 m ASL
Temperature
Precipitation
O c
Min
mm
Date
Max
1 March
3.5
-5
2 March
4.5
-5
3 March
4.5
0.5
4 March
5
0
28
5 March
4
0
80
19
1.8
0.5
About 70 cm o f new snow had been observed a t t h e mine.
r a i n f e l l on 5 March.
Heavy
ACCIDENT SUMMARY
Giant Mascot Mine is i n t h e Coast Mountains i n an a r e a of heavy
snowfall, and i s reached by a road 8.4 krn long from t h e Trans-Canada
Highway. Between km 4.8 and km 7 t h e road c r o s s e s a s t e e p h i l l s i d e w i t h
b l u f f s where avalanches occur f r e q u e n t l y .
On t h e morning o f 5 March t h e bus c a r r y i n g t h e crew was blocked en
r o u t e t o t h e mine by an avalanche a t km 5 . 5 . The bus r e t u r n e d t o Hope
w i t h a l l passengers b u t t h r e e who had t o complete u r g e n t work a t t h e
mine. A b u l l d o z e r c l e a r e d t h e r o a d o f avalanche snow and t h e t h r e e men
followed i n a pick-up t r u c k . The t r u c k waited i n s a f e a r e a s between
avalanches while t h e b u l l d o z e r worked on t h e snow d e p o s i t s , and when a
s t r e t c h o f road was open t h e t r u c k would move t o t h e next s a f e s p o t .
During one o f t h e s e moves, a t km 6 . 3 , t h e t r u c k was h i t by an avalanche,
burying it completely.
RESCUE
The b u l l d o z e r o p e r a t o r observed t h e avalanche a s it h i t t h e t r u c k ,
b u t because t h e road was narrow and bordered by s t e e p h i l l s he could n o t
t u r n h i s machine around t o push away t h e heavy wet snow immediately.
Furthermore, t h e b u l l d o z e r c a r r i e d no snow s h o v e l . H e l p l e s s , t h e
o p e r a t o r walked t o t h e mine about 1 km away and c a l l e d f o r a d d i t i o n a l men.
The r e s c u e workers dug w i t h s h o v e l s and b a r e hands t o uncover t h e cab of
t h e pick-up t r u c k w i t h t h e r o o f crushed by t h e snow, t h e windshield
pushed i n , t h e r e a r window broken, t h e d r i v e r ' s window pushed o u t , and
t h e i n t e r i o r choked w i t h snow. The t h r e e occupants were dead, completely
encased i n t h e avalanche snow. This was about 2 h a f t e r t h e avalanche
had s t r u c k .
Autopsies performed on t h e b o d i e s i n d i c a t e d t h a t i n a l l t h r e e
i n s t a n c e s death had occurred from carbon monoxide poisoning. I t was
presumed t h e snow had packed s o t i g h t l y about t h e d r i v e r t h a t he was
unable t o t u r n o f f t h e i g n i t i o n . The carbon monoxide gas must have b u i l t
up r a p i d l y i n t h e snow-encased v e h i c l e b e f o r e t h e engine s t a l l e d from
l a c k o f oxygen.
AVALANCHE
Heavy snowfall followed by high temperatures w i t h r a i n caused t h e
avalanche, which s t a r t e d a t an a l t i t u d e o f about 700 m ASL, 100 m above
t h e road, and removed about 100 cm o f deep snow on t h e s u r f a c e of t h e
snowcover. The t o t a l depth o f snowcover was g r e a t e r than 2 m.
The average i n c l i n e o f t h e t r a c k was 40 deg, and t h e wet avalanche
snow covered o n l y about 20 m o f t h e road t o a depth of up t o about 10 m .
The snowbank a t t h e edge o f t h e road stopped much o f t h e snow and
c o n t r i b u t e d t o t h e deep d e p o s i t .
COMMENT
People i n v e h i c l e s have u s u a l l y a b e t t e r s u r v i v a l chance t h a n t h o s e
on f o o t o r on s k i s , b u t a s t h i s c a s e demonstrates heavy wet snow f a l l i n g
over a s t e e p s l o p e can crush a v e h i c l e and e n t i r e l y e n c a s e t h e occupants.
The avalanche was narrow, b u t t h e t r u c k happened t o b e e x a c t l y i n i t s
path
.
Rain and high temperatures a f t e r a heavy snowfall a s w e l l a s t h e
number o f avalanches t h a t r a n t h a t day should have made obvious t h e h i g h
avalanche hazard. Under t h e s e circumstances t h e road should n o t have
been used and snow removal work delayed. The b u l l d o z e r o p e r a t o r was
a c t u a l l y much more exposed t o avalanches than t h e r i d e r s o f t h e pick-up
t r u c k , b u t l u c k i l y h e escaped any encounter.
The a c c i d e n t demonstrates t h e importance of having v e h i c l e s and
machines equipped w i t h snow shovels, and p r e f e r a b l y w i t h a probe. With
a shovel t h e b u l l d o z e r o p e r a t o r would have been a b l e t o d i g q u i c k l y t o
t h e cab o f t h e b u r i e d v e h i c l e , although i n t h i s c a s e h i s h e l p would
probably have come t o o l a t e . I t i s n o t s u f f i c i e n t t o e q u i p v e h i c l e s w i t h
s h o v e l s a t t h e beginning of t h e w i n t e r . Frequent i n s p e c t i o n s must e n s u r e
t h a t t h e t o o l s a r e s t i l l t h e r e l a t e r i n t h e season.
WHISTLER MOUNTAIN, WHISTLER, B . C .
8 APRIL 1972
Four s k i e r s k i l l e d
WEATHER
Chart Readings a t W h i s t l e r Alpine S t a t i o n , 1870 m ASL
Temperature
OC
Date
M in
Max
4 A p r i l am
pm
5 A p r i l am
Wind Speed
km/h
Wind
Direction
1
-0.5
0
8-56
(max 104)
no
Pm
6 A p r i l am
0
pm
-6
7 A p r i l am
-7
pm
New
Snow
cm
readings
-
9
30
taken
16-24
(max 104)
-1.5
8 A p r i l am
-8
pm
-7
48-56
(max 80)
AVALANCHE OBSERVATIONS
4 April
-
no avalanche c o n t r o l , no occurrences observed
5 April
-
medium s i z e o c c u r r e n c e s on NW t o NE i n d i c a t o r s l o p e s
Alpine r e g i o n c l o s e d i n mid-morning due t o high winds
6 April
-
medium s i z e occurrences noted on N i n d i c a t o r s l o p e s
attenrpts t o c o n t r o l Alpine T-Bar a r e a abandoned
7 April
-
-
medium s i z e c o n t r o l l e d occurrences on N and NE s l o p e s
one l a r g e c o n t r o l l e d avalanche on a NE s l o p e t h a t has
i n f r e q u e n t occurrences
8 April
-
no occurrences noted
-
On 7 April t h e weather was o v e r c a s t w i t h snowfall i n t h e e a r l y
morning, t h e n cloudy. E x c e l l e n t powder s k i i n g p r e v a i l e d . Owing t o t h e
I
I
h i g h hazard "closed avalanche" s i g n s were placed on t h e t r a v e r s e s a c r o s s
t h e n o r t h s i d e o f W h i s t l e r Peak and t h e Kaleidoscope t r a v e r s e , b u t t h e
enforcement o f c l o s u r e s was d i f f i c u l t because o f p e r s i s t e n t powder s k i e r s .
The n e x t day, 8 A p r i l was cloudy w i t h some sunny p e r i o d s , b u t a t 1450 h a
s q u a l l dropped 10 cm of snow i n 1 h on t h e a l p i n e r e g i o n . A f t e r t h e
s q u a l l , a l l o l d t r a c k s above t h e t r e e l i n e were obscured, b u t no
avalanches were observed and s k i t e s t i n g o f i n d i c a t o r s l o p e s produced no
results.
ACCIDENT SUMMARY
The a c c i d e n t was unobserved, b u t a t 1810 h on 8 A p r i l a man and w i f e
were r e p o r t e d missing by a f r i e n d when t h e y f a i l e d t o p i c k up a n i n f a n t
l e f t w i t h t h e mountain b a b y - s i t t i n g s e r v i c e .
RESCUE
The RCMP was n o t i f i e d a t 1810 h and t h e s k i p a t r o l a t 1900 h. The
f r i e n d r e p o r t i n g t h e l o s t couple i n d i c a t e d t h a t they had intended t o s k i
i n t h e West Bowl a r e a . A t 1930 h two o t h e r people were r e p o r t e d missing
by f r i e n d s who s a i d t h a t t h e f o u r missing s k i e r s knew each o t h e r and had
been s e e n t o g e t h e r a t 1300 h i n t h e Round House a r e a .
By 2030 h seventeen s e a r c h e r s had g a t h e r e d a t t h e bottom of t h e
mountain f o r a s t a n d a r d n i g h t s e a r c h . A t 2145 h t h e search p a r t i e s l e f t
t h e t o p o f t h e mountain, checked l i k e l y a r e a s , and r e p o r t e d i n by 0200 h
on 9 A p r i l . Because t h e s e a r c h was considered thorough, i t was decided
t o postpone f u r t h e r o p e r a t i o n s u n t i l d a y l i g h t when an e x t e n s i v e a e r i a l
s e a r c h of t h e a l p i n e a r e a s could b e made.
A t 0615 h on 9 A p r i l t h e s e a r c h was resumed by h e l i c o p t e r . I t
covered a l l a l p i n e a r e a s , b u t no evidence o f t r a c k s o r avalanche a c t i v i t y
could b e found. F l a t l i g h t hampered t h e o b s e r v a t i o n s a t times, b u t i n
g e n e r a l t h e v i s i b i l i t y was good. A t 0800 h t h e h e l i c o p t e r r e t u r n e d t o
t h e b a s e t o allow t h e o b s e r v e r s t o o r g a n i z e a ground s e a r c h . A t 0845 h
t h e f i r s t v o l u n t e e r s e a r c h p a r t i e s were despatched t o t h e a l p i n e a r e a and
a t t h e same time a n o t h e r a e r i a l s e a r c h was c a r r i e d o u t . E f f o r t s
c o n c e n t r a t e d i n t h e West Bowl, b u t s e v e r a l p a r t i e s were s e n t t o o t h e r
p o s s i b l e a r e a s . About noon on t h e 9 t h it s t a r t e d t o snow again, w i t h
l i g h t winds.
A s a r e s u l t o f a r a d i o appeal f o r any i n f o r m a t i o n about t h e f o u r
missing s k i e r s r e p o r t s were r e c e i v e d a t 1530 h i n d i c a t i n g t h a t t h e p a r t y
had been seen a t t h e t o p o f t h e Alpine T-Bar a t 1440 h on 8 April and
probably on t o p o f a r i d g e bounding t h e Back Bowl a t 1450 h. The s e a r c h
then c o n c e n t r a t e d i n t h e Back Bowl a r e a . A t 1900 h a l l s e a r c h e r s r e p o r t e d
a t t h e bottom o f t h e mountain and t h e o p e r a t i o n s were c a l l e d o f f u n t i l
morning.
A t 0700 h on 10 A p r i l t h e s e a r c h was resumed; t h e snowfall had
continued d u r i n g t h e n i g h t and c o n t i n u e d throughout t h e day. The s e a r c h
c o - o r d i n a t o r s , now having t h r e e h e l i c o p t e r s and two RCMP s e a r c h dogs a t
-72-
I
t h e i r d i s p o s a l , c o n c e n t r a t e d t h e i r e f f o r t s i n t h e a r e a s a c c e s s i b l e from
the party's last-seen point.
A t 1200 h dog No. 1 was s e n t t o check avalanche d e p o s i t s found by a
ground p a r t y i n t h e Burnstew Basin a r e a . Dog No. 2 was s e n t t o avalanche
d e p o s i t s i n t h e Back Bowl n e a r t h e a r e a where t h e s k i e r s had l a s t been
seen. T h i s a r e a i s 400 m west along t h e r i d g e from t h e l a s t - s e e n p o i n t ,
i n t h e o p p o s i t e d i r e c t i o n t o t h e usual t r a v e r s e . The dog was i n a c t i o n
a t t h e s i t e a t 1300 h, t h e h a n d l e r i n s t i t u t i n g a g r i d p a t t e r n s e a r c h
working down from t h e t o p of t h e d e b r i s a r e a . The avalanche snow was
d i s g u i s e d by new snow and r e s c u e personnel had d i f f i c u l t y d e f i n i n g i t .
A t t h e same time a l l o t h e r ground s e a r c h e f f o r t s were withdrawn because
t h e s e a r c h e r s had s t a r t e d a number o f new avalanches and t h e hazard was
increasing.
A t 1430 h dog No. 2 l o c a t e d t h e f i r s t v i c t i m and a t 1500 h t h e second
one. By 1515 h t h e two remaining v i c t i m s had been discovered. A l l were
b u r i e d about 1.2 m below t h e snow s u r f a c e , f a c e down, heads downhill, i n
a l i n e a c r o s s t h e h i l l , s e p a r a t e d from each o t h e r by about 2 m. The
b o d i e s were t r a n s p o r t e d from t h e a r e a i n toboggans and over-snow v e h i c l e s .
Death i n each c a s e was caused by s u f f o c a t i o n , although a l l had a l s o
sustained multiple injuries.
AVALANCHE
The avalanche was probably formed by t h e s h o r t snowfall accompanied
by extremely s t r o n g wind i n t h e a f t e r n o o n . I t had f r a c t u r e d a t an
a l t i t u d e o f 1870 my w i t h an e s t i m a t e d depth o f 1 . 0 m i n t h e wind-deposited
snow. A dry s o f t s l a b , it r a n i n an unconfined manner w i t h a width of
approximately 50 m o v e r 80 m v e r t i c a l l y . The s l o p e has a northwest a s p e c t
and approximately 35 deg i n c l i n a t i o n i n t h e s t a r t i n g zone. The d e p o s i t
had a maximum depth o f 1.5 m y was o f a uniform c o n s i s t e n c y and o n l y j u s t
f i r m enough t o allow walking over t h e s u r f a c e . The avalanche was
probably t r i g g e r e d by t h e s k i e r s themselves.
COMMENT
The weather and t h e snow i n t h e morning o f 8 A p r i l d i d n o t i n d i c a t e
a high avalanche hazard, and s k i i n g i n u n c o n t r o l l e d a r e a s could b e undertaken by experienced s k i e r s w i t h t h e u s u a l p r e c a u t i o n s . The sudden
s q u a l l , w i t h high wind and i n t e n s e s n o w f a l l i n t h e a f t e r n o o n , changed t h e
avalanche hazard from low t o high i n a v e r y s h o r t time. I t shows t h a t
s k i e r s and mountaineers must watch f o r changes i n weather d u r i n g t h e day
and c o n t i n u o u s l y r e - a s s e s s t h e s t a b i l i t y o f t h e snow.
The p a r t y made a common e r r o r o f groups c r o s s i n g avalanche t e r r a i n :
t h e r e was i n s u f f i c i e n t space between them. I f a d i s t a n c e o f 25 t o 30 m
had been maintained between s k i e r s o n l y one o r two o f them would have been
caught i n t h e avalanche so t h a t t h e y could have been rescued immediately
by t h e o t h e r s . A l l t h e v i c t i m s ' s k i b i n d i n g s had r e l e a s e d , b u t t h e s k i s
were s t i l l a t t a c h e d by s a f e t y s t r a p s and t h e p o l e s were a t t a c h e d by t h e
w r i s t s t r a p s . I t i s n o t p o s s i b l e t o t e l l whether freedom from t h i s
equipment would have a s s i s t e d i n s u r v i v a l , b u t s k i s and p o l e s d e f i n i t e l y
a c t a s anchors and decrease chances o f remaining a t t h e s u r f a c e of an
avalanche.
The l a r g e - s c a l e s e a r c h involving v a r i e d personnel i l l u s t r a t e d t h e
importance of recording on a map t h e a r e a s t h a t a r e covered i n t h e
search and t h e need f o r double checking t h e coverage on t h e r e t u r n of t h e
search p a r t i e s . I t was found l a t e r t h a t one p a r t y dispatched t o t h e Back
Bowl on 9 April had n o t a c t u a l l y covered t h e e n t i r e assigned a r e a . The
case showed a l s o t h a t r e p o r t s of w i t n e s s e s must b e t r e a t e d w i t h c a u t i o n .
The i n i t i a l information had placed t h e missing p a r t y a t t h e West B o w l
5 km from t h e a c c i d e n t s i t e , and subsequent r e p o r t s had i n d i c a t e d s e v e r a l
different areas.
The reason f o r t h e long s e a r c h was t h a t t h e avalanche d e p o s i t was
very d i f f i c u l t t o recognize. Several people had s k i e d over t h e a r e a
without n o t i c i n g i t , and only when an experienced mountaineer was c l o s e
t o t h e f r a c t u r e l i n e could he recognize it a s such. The f r a c t u r e l i n e
was n o t even v i s i b l e from t h e run-out zone 80 m below. Once again a dog
proved t o b e most e f f e c t i v e i n f i n d i n g t h e b u r i e d v i c t i m s .
APEX BASIN, NELSON, B .C.
23 APRIL 1972
One s k i e r k i l l e d
WEATHER
Observations a t Nelson 2 Climate S t a t i o n , 602 m ASL
Temperature
O
Date
Precipitation
c
Max
Min
19 A p r i l
14
-1.5
20 A p r i l
15
3
21 A p r i l
13
1.5
22 A p r i l
11
0
23 A p r i l
15
0
mm
5.5
Observations i n t h e Apex Basin on t h e a f t e r n o o n o f Wednesday,
19 A p r i l showed a w e l l c o n s o l i d a t e d snowpack w i t h s u r f a c e h o a r . No
avalanches were observed a t t h i s time. On Friday, 21 A p r i l , 40 cm of
snow f e l l on t h e mountain. On Sunday morning, 23 A p r i l , t h e temperature
was e s t i m a t e d a t 2OC, t h e sky was c l e a r and t h e wind was g u s t i n g from
t h e n o r t h . The t o p 5 cm o f snow were r e p o r t e d t o b e wet.
ACCIDENT SUMMARY
A t 0900 h on 23 April a group of s k i e r s l e f t t h e b a s e o f Y m i r Mountain
by h e l i c o p t e r and landed below t h e peak a t 2070 m ASL. The group intended
t o s k i Y m i r Mountain and had i n s t r u c t i o n s t o s t a y on t h e e a s t s i d e of t h e
b a s i n . One member of t h e p a r t y who had s k i e d t h e a r e a b e f o r e decided t o
descend w i t h h i s son i n a g u l l y t o t h e west o f t h e p a r t y . The son e n t e r e d
t h e c e n t r e o f t h e g u l l y and h i s f a t h e r followed i n approximately t h e same
t r a v e r s e . Suddenly, t h e son n o t i c e d t h e snow moving under him, causing
him t o f a l l . H i s s k i came o f f , snagged a t r e e , and t h e s a f e t y s t r a p
prevented him from b e i n g c a r r i e d very f a r . H i s f a t h e r , however, was
c a r r i e d p a s t him i n t h e moving snow, and when it came t o r e s t was nowhere
t o b e seen.
RESCUE
A f t e r c a l l i n g f o r h i s f a t h e r and looking b r i e f l y over t h e d e b r i s , t h e
son s k i e d down 2 km t o t h e lower h e l i c o p t e r landing s i t e t o c a l l f o r h e l p .
A l l a v a i l a b l e s k i e r s were moved t o t h e a c c i d e n t s i t e by h e l i c o p t e r and
snow-cat, formed p r o b e l i n e s , and by probing w i t h s k i p o l e s and p i n e snags
found t h e v i c t i m 90 min a f t e r he had been b u r i e d . H i s head was about
35 cm below t h e s u r f a c e , f a c e down. The mouth and nose were packed w i t h
snow, and both s k i s and p o l e s were a t t a c h e d t o t h e body when h e was
recovered. Cardiopulmonary r e s u s c i t a t i o n was attempted by a d o c t o r and
members o f t h e s k i p a t r o l , b u t no s i g n s of l i f e r e t u r n e d . S u f f o c a t i o n
was determined a s t h e cause o f death, b u t t h e v i c t i m was probably
unconscious b e f o r e t h e avalanche came t o r e s t because examination
i n d i c a t e d t h a t h e had been h i t on t h e head by h i s s k i .
AVALANCHE
The avalanche was t h e r e s u l t o f a 40 cm deep snowfall on a l a y e r of
s u r f a c e h o a r two days b e f o r e t h e a c c i d e n t and high temperatures on t h e
day of t h e a c c i d e n t . The f a t a l avalanche was t r i g g e r e d by t h e two s k i e r s ,
b u t t h r e e a d d i t i o n a l n a t u r a l avalanches had o c c u r r e d on t h e same day.
The s l a b avalanche f r a c t u r e d a t an a l t i t u d e o f 1930 m, w i t h a width
o f 60 m and a depth of 40 cm. The avalanche snow was mixed dry and wet
and up t o 1 . 8 m deep i n t h e run-out zone. The avalanche p a t h had a
l e n g t h o f about 100 m, an average g r a d i e n t o f about 38 deg, and was
channelled. The a s p e c t was n o r t h .
COMMENT
The a c c i d e n t was t h e consequence o f a bad choice of r o u t e . The
v i c t i m could have avoided t h e avalanche by s k i i n g w i t h t h e r e s t of t h e
group over t h e r i d g e t o t h e e a s t of t h e g u l l y . G u l l i e s a r e hazardous
because t h e y c a t c h d r i f t i n g snow, have s t e e p s l i d e s on which t h e snow
s l i d e s r e a d i l y , and channel t h e moving snow. Anyone caught i n t h e
channelled snow i s u s u a l l y b u r i e d deep.
WHISTLER MOUNTAIN, WHISTLER, B .C.
17 FEBRUARY 1973
One s k i e r b u r i e d
Observations a t W h i s t l e r Alpine S t a t i o n , 1870 m ASL
Temperature
New Snow
Snow Depth
cm
cm
O c
Date
Time
Max
1 3 February
0900
1400
-5
14 February
0900
1400
-1.5
-1.5
15 February
0900
1400
-3
-4
16 February
0900
1400
1.5
1.5
17 February
08 30
1430
1.5
-4
Min
-4
On 16 February t h e sky was o v e r c a s t , w i t h mixed r a i n and snow.
Approximately 13 cm o f new snow f e l l b u t melted during t h e day; t h e r e was
l i t t l e wind. The temperature dropped t o - 5 . 5 ' ~ o v e r n i g h t and 5 cm of snow
f e l l , then it c l e a r e d a g a i n on t h e morning o f 1 7 February. Winds on t h e
morning o f t h e 1 7 t h were e s t i m a t e d a t 8-16 km/h from t h e south, dropping
t o calm d u r i n g t h e day; no avalanche a c t i v i t y was noted and t h e hazard was
thought t o b e low. A t 1430 h t h e temperature was -4.S°C.
ACCIDENT SUMMARY
A s i n g l e s k i e r ascended p a r t way t h e low t r a v e r s e t o Whistle Bowl on
t h e n o r t h s i d e o f W h i s t l e r peak w i t h t h e i n t e n t i o n of s k i i n g down t h e
s t e e p s l o p e below. He was descending from t h e t r a v e r s e when, about one
q u a r t e r o f t h e way down t h e p i t c h , he heard a rumbling sound and looking
back uphi 1 1 saw t h e whole s l o p e moving around him.
Swept downhill by
t h e moving snow, h e found himself a b l e t o s t a y on top by u s i n g a swimming
motion u n t i l t h e l a s t minute when h e was dragged down and b u r i e d . The
time was 1400 h .
RESCUE
The avalanche was observed by people r i d i n g t h e Alpine T-Bar who
r e p o r t e d t h e a c c i d e n t t o a s k i patrolman immediately upon a r r i v a l a t t h e
t o p . He i n t u r n r e p o r t e d it t o t h e a l p i n e o f f i c e by telephone and t h e
prepared avalanche r e s c u e p l a n was a c t i v a t e d a t once. Meanwhile, t h e
patrolman and t h r e e o f h i s f e l l o w s c o l l e c t e d h a s t y s e a r c h packs s t o r e d a t
t h e upper T-Bar terminal and proceeded t o t h e a c c i d e n t s i t e .
Probe l i n e s were s e t up a t 1410 h . One eyewitness who had p r i o r
avalanche experience i n Europe was g i v e n a probe t o check t h e a r e a i n
which h e thought t h e v i c t i m might b e b u r i e d . A t 1413 h a follow-up team,
i n c l u d i n g a doctor, a r r i v e d a t t h e s i t e c a r r y i n g r e s u s c i t a t i o n equipment
and e x t r a probes and s h o v e l s .
A t 1420 h t h e eyewitness l o c a t e d t h e v i c t i m b u r i e d i n a crouched
p o s i t i o n w i t h h i s head about 0.6 m below t h e s u r f a c e . One s k i was s t i l l
a t t a c h e d t o t h e boot and one p o l e t o t h e w r i s t . The man was dug o u t i n a
conscious s t a t e , a b l e t o speak, b u t s h o r t l y l a p s e d i n t o unconsciousness.
The doctor immediately a p p l i e d oxygen and t h e v i c t i m soon r e g a i n e d
consciousness. The o n l y i n j u r y s u s t a i n e d by t h e v i c t i m was a s l i g h t head
c u t from a shovel when h e was dug o u t .
Probing was continued u n t i l 1630 h t o ensure t h a t no o t h e r s had
been b u r i e d and t h e a r e a was f u r t h e r checked by s e a r c h dogs t h e following
morning.
AVALANCHE DATA
The avalanche, t r i g g e r e d by t h e s k i e r , r a n on a c r u s t c r e a t e d by
above-freezing temperatures w i t h mixed r a i n and snow during 16 February
and below-freezing temperatures t h a t n i g h t . New snow, probably combined
w i t h some s o u t h e r l y o r s o u t h w e s t e r l y wind o v e r n i g h t , c r e a t e d t h e s l a b .
The avalanche f r a c t u r e d a t an a l t i t u d e o f 1885 m through a d e p t h of 5-30
cm o f new snaw, was approximately 45 m wide, and r a n approximately 100 m
on an open s l o p e , d e p o s i t i n g snow t o a maximum depth o f 2 m. The s l o p e
g r a d i e n t i n t h e r e l e a s e a r e a was about 40 deg and t h e a s p e c t n o r t h .
COMMENT
Light s n o w f a l l i n t h e a l p i n e a r e a d u r i n g t h e n i g h t o f 16 February
i l l u s t r a t e s t h e importance of minor storms a s p o t e n t i a l hazard b u i l d e r s ,
e s p e c k a l l y i n s k i a r e a s . S e v e r a l s k i e r s had c r o s s e d t h e t r a v e r s e without
a c c i d e n t on 17 February b e f o r e t h e v i c t i m d i d . The l o n e s k i e r was lucky
t o b e observed when h e was caught i n t h e avalanche and h i s s u c c e s s f u l
r e c o v e r y was due p a r t l y t o t h e eyewitness, who c l e a r l y e s t a b l i s h e d t h e
l a s t - s e e n p o i n t a t t h e s i t e , and p a r t l y t o t h e w e l l prepared avalanche
r e s c u e p l a n and equipment o f t h e W h i s t l e r Mountain s k i a r e a . The s e a r c h
equipment l o c a t e d at t h e t o p o f t h e h i g h e s t l i f t d e f i n i t e l y c o n t r i b u t e d
t o t h e speed o f t h e o p e r a t i o n
An a d d i t i o n a l n o t e , t h e b u r i e d s k i e r ' s hands were s t i l l i n t h e p o l e
wrist s t r a p s and t h i s may have c o n t r i b u t e d t o h i s b u r i a l .
BOW SUMMIT, BANFF NATIONAL PARK, ALBERTA
9 DECEMBER 1973
One s k i e r k i l l e d
Observations a t Lake Louise-Temple Warden S t a t i o n , 1980 m ASL
Date
Temperature
OC
Max
Min
New Snow
cm
5 Dec
6 Dec
7 Dec
8 Dec
9 Dec
ACCIDENT SUMMARY
The a c c i d e n t was n o t observed. The v i c t i m was s k i i n g a l o n e on t h e
southwest r i d g e o f Bow Summit and presumably t r i g g e r e d a n avalanche t h a t
engulfed and b u r i e d him. He had n o t r e g i s t e r e d with t h e National Parks
services.
RESCUE
The v i c t i m ' s c a r was parked f o r s e v e r a l days n e a r t h e r a d i o r e p e a t e r
s t a t i o n between t h e Banff-Jasper Highway and t h e Peyto parking l o t .
I n v e s t i g a t i o n s l e d t o t h e conclusion t h a t t h e d r i v e r had probably been
l o s t while s k i i n g i n the area.
On 18 December a s e a r c h was i n i t i a t e d i n t h e a r e a of t h e Peyto
parking l o t . When no c l u e s were found a l a r g e - s c a l e search was organized,
u s i n g dogs, personnel on s k i s , and motorized toboggans. On 19 December a
survey by h e l i c o p t e r l o c a t e d a l a r g e avalanche d e p o s i t above Peyto Lake.
Some h e l i c o p t e r bombing was c a r r i e d o u t and an avalanche was r e l e a s e d on
an a d j a c e n t n o r t h s l o p e .
On 20 December personnel and s e a r c h dogs were flown t o t h e n o r t h s l o p e
d e p o s i t . During t h e s e a r c h a dog t r i g g e r e d a l a r g e f u l l - d e p t h avalanche
which r a n onto Peyto Lake. On 21 December t h e s e a r c h was continued i n t h e
same a r e a and i n t h e lower d e p o s i t i o n a r e a n e a r Peyto Lake.
On 22 December t h e searchers moved back t o t h e parking l o t and began
s e c t i o n a l dog search p a t t e r n s west of t h e parking a r e a . After 2 h a dog
l o c a t e d t h e v i c t i m i n an o l d avalanche deposit 40-70 cm below t h e new
snow s u r f a c e . The dead s k i e r had s e v e r e head i n j u r i e s , and i t was
assumed t h a t he had been unconscious when h e was b u r i e d i n t h e shallow
avalanche, could t h e r e f o r e not f r e e himself, and d i e d from exposure. The
body of t h e victim was removed t o Banff and t h e search concluded.
AVALANCHE
The avalanche t h a t caused t h e a c c i d e n t and o t h e r s t h a t occurred
during t h e search were a t t r i b u t e d t o a weak base of depth h o a r i n t h e
snowcover, a common phenomenon i n t h e Rocky Mountain a r e a . The avalanches
removed t h e f u l l snowcover t o a depth o f about 60 cm. The f a t a l one
occurred i n a small b a s i n with w e s t e r l y aspect, a s l o p e i n c l i n e of about
I t s s i z e could not be e s t a b l i s h e d
35 deg, and a n e l e v a t i o n o f 2,210 m.
because about 40 cm o f new snow had f a l l e n s i n c e t h e a c c i d e n t and made t h e
i d e n t i f i c a t i o n of t h e d e p o s i t d i f f i c u l t .
COMMENT
Although t h e v i c t i m had some mountaineering experience h e neglected
t o inform anybody about h i s plans, and h e s k i e d alone. Skiing alone
proved t o b e a s e r i o u s mistake.
- - - CLIFFS - --
................."'"":
4
19DEC
I
Q,
&
I
HIGHWAY
TO BANFF
PEYTO
LAKE
1885 m
0
0
L'ICTIM'S
C.A R
L0T
-
\SCATTERED
\ TIMBER
\
V l EW
POINT
HIGHWAY
T O JASPER
Figure 26
TRAIL T O
PEYTO GLACIER
.....
BOUNDARIES OF O L D AVALANCHES
A N D THOSE I N I T I A T E D D U R I N G
SEARCH. W I T H DATES
SEARCHED AREAS. W I T H DATES
@
L O C A T I O N OF VICTIM
a
F A L L L I N E O F V A R I O U S SLOPES
R O C K Y AREAS
Sketch map of avalanche a r e a , Bow Summit
RUTH -VERMONT MINE, PURCELL MOUNTAINS, GOLDEN, B .C
.
1 6 JANUARY 19 74
Buildings d e s t r o y e d , s e v e r a l b u j l d i n g s h e a v i l y damaged,
Observations a t Bugaboo Creek Lodge, 1490 m ASL (20 km SE o f Mine)
Temperature
OC
Max
Min
Date
New Snow
cm
11 January
-21
- 38
12 January
-15.5
-26.5
26
1 3 January
0
41
14 January
3
- 19
- 2
15 January
4
0
16 January
2
0.5
1
25
11
Approximately 140 cm o f new snow f e l l a t t h e mine d u r i n g t h e f o u r
days p r e v i o u s t o 16 January. P e r i o d s o f s t r o n g wind and temperatures
around 0 "C were observed
.
ACCIDENT SUWRY
A t approximately 0230 h on 1 5 January a loud rumbling was h e a r d i n
t h e camp a r e a . I n v e s t i g a t i o n t h e following morning r e v e a l e d t h a t a n
avalanche from t h e C h a r l o t t e path had damaged t h e o f f i c e b u i l d i n g and
a n o t h e r a f u e l tank and a van. The o i l shed, metals l a b o r a t o r y and m i l l
a l s o were damaged by an avalanche from t h e Sheba p a t h .
A t 2230 h on 15 January Bunkhouse 1 was shaken by a n o t h e r avalanche.
On i n v e s t i g a t i o n it was found t h a t b o t h Bunkhouses 1 and 2 had been h i t
and seven rooms d e s t r o y e d i n Bunkhouse 2. F o r t u n a t e l y they were
unoccupied a t t h e t i m e . The avalanche, from t h e Vermont E a s t p a t h ,
seemed t o have jumped t h e r o o f o f Bunkhouse 1.
A t 2042 h on 16 January t h e power house was h i t and b u r i e d and power
went o f f a t t h e camp. The mine crew t h e n withdrew underground i n t o t h e
mine t o spend t h e n i g h t . Daylight r e v e a l e d t h a t t h e power house was
completely b u r i e d , a major s e c t i o n o f t h e mine d r y missing, t h e machine
shop b a d l y damaged, t h e s t o r a g e b u i l d i n g and o i l shed missing, t h e m i l l
damaged, and t h e metals l a b o r a t o r y f u r t h e r damaged. Excessive amounts of
snow and s u r f a c e v a r i a t i o n s made it c l e a r t h a t more t h a n one avalanche
had o c c u r r e d i n t h e a r e a .
In a l l , s i x b u i l d i n g s were destroyed, s i x h e a v i l y damaged, and
v a r i o u s equipment destroyed o r damaged. The t o t a l l o s s was estimated a t
$600 000. F o r t u n a t e l y t h e r e was o n l y a small maintenance crew a t t h e
mine and t h e m i l l was s h u t down. None of t h e employees was i n j u r e d .
AVALANCHE DATA
The avalanches were caused by heavy snowfalls, s t r o n g winds and
A s u r f a c e h o a r l a y e r had formed
temperatures around and exceeding O'C.
on t h e snow base p r i o r t o t h e new snowfalls. The mine s e t t l e m e n t i t s e l f
l i e s a t 1640 m ASL on Vermont Creek, and t h e avalanches s t a r t a t
e l e v a t i o n s varying between 2000 and 2600 m ASL. The Sheba and Ruth
avalanches p r e s e n t t h e g r e a t e s t t h r e a t t o t h e i n s t a l l a t i o n . Those of
16 January (on t h e s e p a t h s ) probably contained dry, l i g h t snow, c a r r y i n g
through t h e a i r ; they d i d not d e p o s i t snow on t h e road above t h e camp and
appeared t o have landed d i r e c t l y on t h e powerhouse.
COMMENT
The o r i g i n a l mine camp was b u i l t a t t h i s l o c a t i o n i n 1926 and t h e r e
i s no record o f i t s being h i t by a n avalanche. The modern camp was
opened i n 1965. I t was l a r g e r than t h e o l d camp and extended i n t o unsafe
a r e a s . During t h e w i n t e r o f 1967-68 an avalanche, p o s s i b l y from Sheba,
destroyed one b u i l d i n g i n t h e v i c i n i t y of t h e o i l s t o r a g e . On 7 December
1970 t h e howerhouFe r o o f was blown o f f by an avalanche from t h e Ruth path
and another from Sheba l a t e r i n t h e y e a r narrowly missed t h e o i l s t o r a g e .
.cn
oram
a,&
mkc,
\o
a
C
U1CI a,
k
d
s cd
..ad
Q Q c d
2
05
cncds
2 acd
C
I
53 23 es
0 0
cn k-a
d
M
cd
G a
.rl Q) n
*kc,
0 a,W
O W Q )
d cnd
.. s u
4
VERMONT
VERMONT
EAST
CREEK
0
0
/
0
SHEBA
RUTH
--
OUTLINE AVALANCHE DEPOSITS
DESTROYED STRUCTURES
DAMAGED STRUCTURES
I
0
I
50
1
100 m
Figure 27(b)
1 BUNKHOUSE 1
2 BUNKHOUSE 2
3 OFFICE
4 MILL
5 METAL LAB
6 CRUSHER HOUSE
7
8
9
10
11
12
OIL SHED
STORAGE
MINE DRY
MACHINE SHOP
POWER HOUSE
OIL TANKS MOVED
Plan o f mine showing o u t l i n e o f
a v a l a n c h e s , 16 J a n u a r y 1974.
.
NORTH ROUTE CAFE, TERRACE, B .C
22 JANUARY 19 74
Seven occupants o f a b u i l d i n g k i l l e d , one rescued unharmed,
b u i l d i n g s destroyed
Observations a t T e r r a c e A i r p o r t , 219 m ASL
Temperature
O
c
New Snow
Rain
mm
Date
Max
Min
cm
1 5 January
- 16
14
16 January
- 17
17 January
-12
18 January
0
19 January
0
- 24
- 27
- 20
- 24
- 4
2
-
21 January
22 January
20 January
-
Precipitation
mm
10.9
14
99
22
15.5
9
7.1
4
6
4.8
0
- 4
6
5.8
3
-
4
40
0.3
26.9
The a c c i d e n t s i t e is 45 km west o f T e r r a c e on Highway 16 t o P r i n c e
Rupert and experience has shown t h a t s n o w f a l l s t h e r e a r e u s u a l l y g r e a t e r
than t h o s e a t T e r r a c e A i r p o r t . A t t h e microwave s t a t i o n , McLean Mountain,
e l e v a t i o n 1130 m and 37 km west o f t h e North Route Cafe, t h e temperature
was -6 t o - 3 ' ~ between 17 January and 21 January, then it climbed t o O°C
on 22 J a n u a r y .
ACC I DENT SUMMARY
Between 2100 h on 21 January and 0800 h on 22 January 40 cm o f new
snow f e l l a t T e r r a c e , making d r i v i n g and snow removal d i f f i c u l t on t h e
highways. The mail t r u c k l e f t T e r r a c e f o r P r i n c e Rupert a t about 0130 h .
Enroute, i t overtook a c a r d r i v e n by a businessman from P r i n c e Rupert who
was unable t o n e g o t i a t e t h e r o a d . Abandoning h i s v e h i c l e he continued
h i s journey i n t h e mail t r u c k . A t t h e North Route s e r v i c e s t a t i o n , a t
km 45, t h e two occupants o f t h e mail t r u c k met a n o t h e r P r i n c e Rupert
businessman w i t h a 4-wheel d r i v e pickup t r u c k . The group proceeded west
i n convoy t o km 55 where t h e y encountered a truck-plow a t t e m p t i n g t o
c l e a r t h e road of avalanches. It became e v i d e n t t h a t t h e plow would b e
unable t o c l e a r t h e road, and it was decided t o abandon it s i n c e i t was
trapped between s l i d e s .
The group, now f o u r s t r o n g , r e t u r n e d t o t h e s e r v i c e c e n t r e a t 0530 h
t o w a i t o u t t h e storm. The s e r v i c e c e n t r e c o n t a i n e d a coffeeshop,
s e r v i c e s t a t i o n , and motel and was occupied by t h e owner, h i s daughter, a
cook, and a machine o p e r a t o r . The t r a v e l l e r s s e t t l e d down i n t h e c o f f e e shop, p a s s i n g t h e time napping, p l a y i n g c a r d s , and d r i n k i n g c o f f e e .
A t 0800 h t h e f o u r g u e s t s and t h e s h o r t - o r d e r cook were i n t h e cafe,
t h e owner and t h e machine o p e r a t o r were i n t h e back o f t h e b u i l d i n g , where
a l s o t h e daughter l a y s l e e p i n g . S h o r t l y a f t e r 0800 h a loud "crack1' was
heard and suddenly a l l were tumbling through snow.
RESCUE
A t approximately 0950 h on 22 January a h e l i c o p t e r , which was
checking f o r broken telephone l i n e s along t h e Skeena River, came a c r o s s
t h e avalanche d e b r i s . The l o c a l Royal Canadian Mounted P o l i c e were
immediately informed t h a t no s i g n s o f l i f e could b e s e e n i n a r a p i d check
of the area.
A t 1000 h t h e c a l l f o r manpower and equipment was p u t o u t t o v a r i o u s
p r o v i n c i a l and municipal groups. A t 1030 h t h e f i r s t p a r t y , c o n s i s t i n g of
p o l i c e , a s e a r c h dog, and a f i r s t - a i d u n i t , was d i s p a t c h e d t o t h e s c e n e .
A t 1045 h t h e f i r s t follow-up column was d i s p a t c h e d w i t h equipment t h a t
i n c l u d e d probes, s h o v e l s , r a d i o s and snowshoes. A t 1130 h t h e a r e a had
been searched by t h e dog t o no a v a i l . 'Ituenty men were on s i t e w i t h probes
and shovels by 1330 h .
.
The avalanche snow ranged from
Probing was exceedingly d i f f i c u l t
1 t o 8 m i n depth and was strewn w i t h housing d e b r i s and t r e e s up t o
0 . 5 m i n diameter. Front-end l o a d e r s and s h o v e l s were then used t o c l e a r
t h e d e b r i s t o ground, beginning a t t h e w e s t e r l y e x t r e m i t y o f t h e avalanche.
With t h e p o s s i b i l i t y o f f u r t h e r r e l e a s e s , a guard was p o s t e d .
A t 1445 h t h e body o f t h e truck-plow o p e r a t o r was l o c a t e d , f a c e down,
b u r i e d under 3.6 m o f snow. A t 1515 h t h e mail t r u c k d r i v e r was found
a l i v e , i n a s i t t i n g p o s i t i o n , under 1 . 5 m o f snow; h e was removed by
h e l i c o p t e r t o t h e h o s p i t a l . The cook's body w a s l o c a t e d , f a c e down under
2.5 m of snow a t 1630 h . By 1645 h t h e r e were approximately 65 r e s c u e r s
on s i t e . A t 1730 h t h e body o f one o f t h e businessmen was l o c a t e d beneath
5 m of snow. A s dark loomed and t h e guard could no l o n g e r observe t h e
avalanche path, a temporary h a l t was c a l l e d a t 1800 h f o r i n s t r u c t i o n i n
means o f s u r v i v a l i f a n o t h e r avalanche s h o u l d o c c u r . Work was l a t e r
resumed, and a t 2355 h t h e body o f t h e machine o p e r a t o r was recovered,
b u r i e d f a c e down 3 m deep.
A t 0230 h on 23 January t h e owner's body w a s recovered, l y i n g s i d e ways under 3 m o f snow and d e b r i s . The body of t h e second businessman
was l o c a t e d a t 0310 h, f a c e down under 5 m o f d e b r i s . A t 0330 h t h e body
o f t h e daughter w a s found, f a c e up i n bed, below a p o r t i o n o f r o o f under
1.8 m o f snow. A t 0630 h t h e s e a r c h was suspended owing t o s t e a d y r a i n ,
u n c e r t a i n t y o f avalanche t a z z r d , and' t h e f a c t t h a t a l l persons known t o
have been a t t h e s i t e were accounted f o r .
A meeting o f rescue and experienced avalanche personnel was h e l d
l a t e r on 23 January and i t was decided t h a t explosive c o n t r o l of t h e
s l o p e s above t h e s i t e should b e c a r r i e d o u t . A f t e r h e l i c o p t e r bombing on
t h e morning o f t h e 24th, with no s i g n i f i c a n t r e s u l t s , t h e clean-up s e a r c h
was reswned and completed without l o c a t i n g any f u r t h e r v i c t i m s .
AVALANCHE PATH
The avalanches a t t h e North Route Cafe o r i g i n a t e i n a l a r g e c i r q u e
t h a t c o n t a i n s s e v e r a l independent s t a r t i n g zones. Where t h e avalanche of
22 January 1974 s t a r t e d could not b e e s t a b l i s h e d exactly, b u t t h e most
l i k e l y p l a c e is a s t e e p s l o p e between 1100 and 1200 m e l e v a t i o n on t h e
west s i d e .
The avalanches a r e funnelled i n t o a 50 m wide, s t r a i g h t , s t e e p - s i d e d
v a l l e y opening i n t o an a l l u v i a l f a n 650 m u p h i l l from t h e s e r v i c e c e n t r e .
The a l l u v i a l fan has a n i n c l i n a t i o n of 14 deg. Most avalanches r u n o u t
on i t and u s u a l l y have n o t come c l o s e r t h a n 300 m t o t h e s e r v i c e c e n t r e .
S c a t t e r e d poplar t r e e s and broken wood on t h e lower p a r t o f t h e a l l u v i a l
fan demonstrate, however, t h a t avalanches had reached t h e highway and
railway l i n e b e f o r e t h e s e r v i c e c e n t r e was b u i l t , through two narrow gaps
i n t h e c o n i f e r o u s f o r e s t (Figure 28). The w e s t e r l y gap, 10 m wide, i s i n
a s t r a i g h t l i n e w i t h t h e d i r e c t i o n of t h e narrow v a l l e y above and was
obviously c r e a t e d by f a s t d r y snow avalanches t h a t d i d not change t h e i r
d i r e c t i o n o f motion a f t e r l e a v i n g t h e v a l l e y . The e a s t e r l y , 25 m wide
gap was probably made by slower wet snow avalanches, which would tend t o
follow t h e f a l l l i n e o v e r t h e s i d e o f t h e a l l u v i a l fan. I n 1971 and 1972
avalanches reached t h e highway through t h i s opening 60 m e a s t of t h e
service centre.
The s e r v i c e s t a t i o n - c a f e - m o t e l complex was b u i l t underneath t h e
w e s t e r l y opening o f t h e dense f o r e s t , and i n t h e path t h a t dry, r a p i d l y moving avalanches would b e expected t o t a k e .
AVALANCHE
As i s u s u a l l y t h e c a s e f o r l a r g e d e s t r u c t i v e avalanches, t h a t on
22 January 1974 was t h e r e s u l t o f a combination of s e v e r a l weather f a c t o r s :
-
Unusually deep snow. The t o t a l snowfall a t Terrace A i r p o r t f o r
January 1974 was a new record f o r t h e month.
-
A heavy snowstorm t h a t d e p o s i t e d 135 cm of new snow between 16 and
18 January and 60 cm between 19 and 22 January a t T e r r a c e A i r p o r t .
A t t h e North Route s i t e t h e snowfall was probably g r e a t e r by one
third.
-
A high p r e c i p i t a t i o n r a t e o f 2.8 mm/h between 2100 h on 21 January
and 0800 h on 22 January.
- Low
temperature during t h e week previous t o t h e snowstorm, r i s i n g
t o O°C during t h e storm.
-
Moderate wind.
The avalanche moved through t h e f o r e s t above t h e s e r v i c e c e n t r e without breaking f i r t r e e s w i t h diameters g r e a t e r than 0.5 m, b u t i t s t r i p p e d
t h e t r e e s o f t h e i r branches up t o 10 m above ground. The average depth of
avalanche snow i n t h e a r e a surrounding t h e b u i l d i n g s and on t h e highway
was 1 m, b u t t h e snow was up t o 8 m deep a t t h e b u i l d i n g s , probably
because i t was caught by plowed snow and t h e s t r u c t u r e s . The avalanche
r a n o u t on t h e i c e of t h e Skeena River, with t h e t i p o f t h e d e p o s i t 250 m
p a s t t h e s e r v i c e c e n t r e . These o b s e r v a t i o n s l e a d t o t h e conclusion t h a t
t h e avalanche must have contained d r y snow with a r a t h e r low d e n s i t y ,
probably between 20 and 50 kg/m3. ?he estimated speed of t h e avalanche
when it h i t t h e b u i l d i n g s was 30 m s - l (108 km/h).
COMMENT
The s e r v i c e c e n t r e was l o c a t e d i n t h e run-out zone o f l a r g e
avalanches t h a t would probably occur once i n about 15 y e a r s . Damage t o
t h e f o r e s t above and below t h e s e r v i c e c e n t r e c l e a r l y i n d i c a t e d t h a t
avalanches had reached t h e s i t e b e f o r e . The growth p a t t e r n o f t h e t r e e s ,
obvious on a i r photos, a l s o i n d i c a t e s a n avalanche s i t e . Unfortunately, t h e
hazard was n o t recognized when t h e s e r v i c e c e n t r e was b u i l t about 1964,
and l a t e r when avalanches d i d come c l o s e t h e warning went unheeded.
?he d i s a s t e r i n i t i a t e d an e x t e n s i v e and s u c c e s s f u l s a f e t y and c o n t r o l
program f o r B r i t i s h Columbia highways through t h e M i n i s t r y of Highways and
P u b l i c Works.
NARROW
VALLEY
-
TO P R I N C E R U P E R T
-
'SERVICE STATION
/%/AND
CAFE
I
r
I
-
-
TO TERR ACE
HIGHWAY
RAILWAY
S K E E N A RIVER
DEP' O S I T E D A V A L A N C
Figure 28
SNOW
Avalanche s i t e a t North Route Cafe,
2 2 January 1974
MICA MOUNTAIN, CARIB00 MOUNTAINS, VALEMOUNT, B.C.
17 FEBRUARY 1974
One s k i e r k i l l e d , two s k i e r s i n j u r e d
WEATHER
Friday, 15 February, was a cool day w i t h about 5 cm o f s n o w f a l l .
The mountain was s k i e d f o r t h e f i r s t time t h a t w i n t e r by numerous s k i e r s
and no avalanche occurrences were noted. Sunday, 1 7 February, was
f a i r l y warm, n o t unusual f o r t h a t time o f t h e y e a r . Light snowfall had
occurred s i n c e t h e 15th. The weather s t a t i o n a t Blue River, e l e v a t i o n
681 m ASL, r e p o r t e d 7 cm o f new snow.
ACC IDENT SUMMARY
About noon on 17 February t h r e e groups o f s k i e r s landed by
h e l i c o p t e r on Mica Mountain w i t h t h e i n t e n t i o n o f s k i i n g t h e same southe a s t s l o p e a s on t h e previous Friday. The o l d t r a c k s could s t i l l b e
s e e n . Each group comprised a guide and n i n e c l i e n t s , and a l l c a r r i e d
avalanche r e s c u e t r a n s c e i v e r s
.
Guide 1 descended w i t h h i s group on t h e n o r t h e a s t s i d e of t h e s l o p e ,
e n t e r i n g t h e avalanche t r a c k about halfway down. Towards t h e bottom h e
s k i e d w i t h a slower member o f t h e group w h i l e t h e r e s t o f h i s c l i e n t s
waited below and t o t h e s i d e . Guide 2 took h i s group t o t h e southwest
s i d e o f t h e s l o p e and i n t o t h e t r e e s along t h e edge of t h e p a t h .
Guide 3 e n t e r e d t h e s l o p e from t h e t o p c o r n e r ( s e e Figure 29) i n
o r d e r t o t e s t t h e snow. One s k i e r r e q u e s t e d permission t o advance
because he wanted t o t a k e movie p i c t u r e s o f h i s companions. A f t e r
checking t h e s l o p e t h e guide s a i d i t was a l l r i g h t t o go down a couple
of hundred f e e t . A s t h e photographer set up h i s camera f o u r o t h e r s k i e r s
e n t e r e d t h e t o p o f t h e p a t h . Suddenly t h e whole s l o p e f r a c t u r e d around
them; t h e f o u r s k i e r s , t h e guide, and t h e photographer were caught i n t h e
moving snow.
A s t h e avalanche flowed down i t gained momentum and developed a
powder component t h a t caught one s k i e r o f group 2 and slammed him through
t h e small t r e e s . The powder avalanche advanced f u r t h e r down t h e s l o p e
than t h e flowing p a r t and s t r u c k Guide 1 and one o f h i s c l i e n t s , who,
completely unprepared, tumbled o v e r t h e snow.
RESCUE
When t h e snow had stopped, Guide 3 was p a r t l y b u r i e d b u t was a b l e t o
d i g himself o u t . He scanned t h e s l o p e quickly, n o t i n g i n t h e same a r e a
t h e f o u r s k i e r s , a l l p a r t l y b u r i e d , one w i t h o n l y a hand showing. There
was no s i g n o f t h e photographer.
With t h e g u i d e ' s h e l p t h e f o u r were immediately f r e e d and prepared
f o r a s y s t e m a t i c search with rescue t r a n s c e i v e r s . One s k i e r whose
i n j u r y would n o t allow movement was l e f t a t t h e s i t e while t h e o t h e r s
moved slowly down t h e s l o p e w i t h t h e guide, t r a n s c e i v e r s switched t o
r e c e i v e . About 25 min a f t e r t h e avalanche had occurred t h e b u r i e d s k i e r
was l o c a t e d under about 1 m o f avalanche snow, i n a s t a n d i n g p o s i t i o n ,
unconscious, and n o t b r e a t h i n g . A r t i f i c i a l r e s p i r a t i o n was immediately
i n i t i a t e d . So t i g h t l y packed was t h e snow t h a t t h e a r e a around t h e
v i c t i m ' s c h e s t had t o b e dug o u t b e f o r e a i r could b e forced i n t o t h e
lungs
.
I n Group 2 t h e man who had been c a r r i e d through t h e t r e e s was
s e r i o u s l y i n j u r e d , b u t no one was b u r i e d . In Group 1, t h e guide was
shaken and one woman s k i e r i n j u r e d . Head counts were taken and a l l t h e
s k i e r s accounted f o r .
A doctor flown t o t h e s i t e determined t h a t nothing could b e done
f o r t h e b u r i e d s k i e r , who was l a t e r diagnosed t o have died o f s u f f o c a t i o n .
The body and t h e i n j u r e d s k i e r s were flown o u t t o Valemount.
AVALANCHE
The avalanche was caused by deep s l a b i n s t a b i l i t y . The snowpack
contained depth h o a r and c r u s t s with some new snow a t t h e t o p . The bed
s u r f a c e was, on t h e average, 70 cm below t h e s u r f a c e and c l o s e t o t h e
ground.
The avalanche s t a r t e d a t an a l t i t u d e o f 2260 m with a width o f 300 m
and on a s l o p e o f 38 deg, s o u t h e a s t a s p e c t . A dry snow avalanche, i t had
a mixed flowing and powder motion and r a n over 1000 m v e r t i c a l l y . The
deposited avalanche snow was widely s c a t t e r e d throughout t h e path and
reached a maximum depth o f 3 m.
COMMENT
I t is o f t e n d i f f i c u l t t o p r e d i c t t h e s t a b i l i t y of deep s l a b s , and
i n any c a s e s t a b i l i t y may change over s h o r t periods o f time. On Friday
t h e mountain was h o s p i t a b l e ; on Sunday, a f t e r a r e l a t i v e l y minor snowfall,
it was n o t .
The a c c i d e n t r e v e a l s one of t h e problems o f s k i i n g i n l a r g e groups
when s k i e r s a r e anxious t o make new t r a c k s i n powder snow. The f i r s t
s k i e r s can choose r e l a t i v e l y s a f e t e r r a i n , b u t t h e o t h e r s o f t e n have t o
use t h e c e n t r e o f an avalanche path i n o r d e r t o f i n d untracked snow.
Once a g a i n avalanche rescue t r a n s c e i v e r s proved t o b e an excel1 e n t
t o o l f o r r a p i d l y l o c a t i n g a b u r i e d v i c t i m i n a l a r g e avalanche. I t i s
u n f o r t u n a t e t h a t he was n o t found a l i v e a f t e r s o s h o r t a b u r i a l time.
F i g u r e 29
Avalanche p a t h a t Mica Mountain, 17 February 1974
x Location o f p a r t i a l l y b u r i e d s k i e r s
@ Location o f v i c t i m
C i r c l e d a r e a s i n d i c a t e p o s i t i o n o f Groups 1 and 2
(Photo c o u r t e s y Canadian Mountain Holidays Ltd.)
LOOKOUT MOUNTAIN, SUNSHINE AREA, BANFF, ALBERTA
30 MARCH 1974
One s k i e r k i l l e d
The weather i n t h e Sunshine a r e a was c l e a r with below-freezing
temperatures p r i o r t o 30 March. Due t o d r i f t i n g , loose snow had
accumulated on l e e s l o p e s . The snow i n the a r e a , however, was g e n e r a l l y
stable.
ACCIDENT SUMMARY
The v i c t i m was l a s t seen by a s k i i n g companion a t t h e t o p of
Brewster C h a i r l i f t between 1130 and 1200 h on 30 March. L a t e r i n v e s t i g a t i o n s i n d i c a t e d t h a t t h e v i c t i m must have s k i e d i n a northwesterly
d i r e c t i o n along t h e bounding fence on t h e r i d g e o f Lookout Mountain. A t
the end o f t h e fence a n a t u r a l rock o b s t r u c t i o n d i v e r t s s k i e r s back t o
t h e Angel r u n and t h e base s t a t i o n . The v i c t i m probably s k i r t e d t h e
o b s t r u c t i o n t o go t o t h e c l i f f i n order t o take photographs. He may
have crossed t h e rocks and ventured o u t on a cornice, which broke and
f e l l with him, s t a r t i n g an avalanche on t h e s l o p e below.
RESCUE
Although t h e companion was unable t o f i n d h i s f r i e n d a t t h e bottom
o f t h e s k i run, h e thought nothing o f i t . Even when t h e f r i e n d f a i l e d
t o r e t u r n t h a t n i g h t h i s companion thought perhaps h e had met someone
e l s e and stayed o u t f o r t h e evening. On t h e following morning, however,
31 March, a t about 1100 h h e r e p o r t e d t h e missing person t o t h e s k i
p a t r o l . The p a t r o l i n i t i a t e d a search o f t h e s k i a r e a and a t 1500 h
made a r e p o r t t o t h e National Park Wardens.
A search on f o o t and by h e l i c o p t e r was immediately c a r r i e d o u t over
a wide a r e a u n t i l dark with no r e s u l t s . A t 0700 h on 1 April t h e search
was recommenced, using dogs, personnel on s k i s and a h e l i c o p t e r . A t
0900 h a p a r t y on s k i s and observers i n t h e h e l i c o p t e r noticed two s l i d e s
i n t h e Delirium Dive a r e a and f u r t h e r i n v e s t i g a t i o n r e v e a l e d a broken
c o r n i c e below t h e fence.
A follow-up p a r t y with two dogs was dispatched, a r r i v i n g a t the
scene a t 1310 h . One o f t h e dogs immediately l o c a t e d a s k i p o l e . The
s e a r c h e f f o r t s continued f o r over 4 h b u t were suspended with t h e coming
o f darkness
.
On 2 April a t 0800 h t h e search was resumed, and a t 1050 h t h e
v i c t i m was found by a warden s e r v i c e dog. The body was i n an i n v e r t e d
p o s i t i o n , with t h e l e f t boot 60 cm below t h e snow s u r f a c e . The cause
o f death was determined t o be s u f f o c a t i o n .
AVALANCHE
The c o r n i c e probably broke under t h e weight o f t h e v i c t i m and, i n
t u r n , r e l e a s e d a small s l a b on t h e s l o p e below. The c o r n i c e broke a t an
e l e v a t i o n o f 2250 m and t h e ensuing avalanche had a v e r t i c a l f a l l of
about 140 m. The s l o p e below t h e c o r n i c e has a n o r t h e a s t a s p e c t and an
average g r a d i e n t of about 45 deg. The avalanche snow was d e p o s i t e d t o a
depth of about 3.5 m and was found t o b e extremely dense during t h e
rescue.
COMMENT
The s k i e r was a v i c t i m o f l a c k of knowledge o f t h e hazards i n
mountains. Common s a f e t y r u l e s d i c t a t e n o t s t e p p i n g on c o r n i c e s because
t h e i r s t a b i l i t y is u s u a l l y u n p r e d i c t a b l e . I t i s n o t s u r p r i s i n g t h a t t h e
f a l l i n g c o r n i c e r e l e a s e d a s l a b avalanche below because deep, d r i f t i n g
snow u s u a l l y has accumulated t h e r e , and t h e impact o f t h e f a l l i n g c o r n i c e
would b e s t r o n g enough t o s e t t h i s snow i n motion.
'EAK OF
OOKOUT MTN
POINT
F i g u r e 30(a)
Contour map o f Lookout Mountain, 30 March 1 9 7 4 .
VERY STEEP
TERRAIN
ROCK
l4
Figure 30(b)
50 m
Sketch o f avalanche p a t h , Lookout Mountain, 30 March 1974.
GRANITE MOUNTAIN, ROSSLAND, B .C
.
16 MARCH 1975
Two s k i e r s i n j u r e d
WEATHER
Observation a t Rossland MacLean S t a t i o n , 1082 m ASL
Temperature
O
Precipitation
c
Date
Max
Min
mm
9 March
2
-4
7.6
10 March
2
-3
3.8
11 March
3
12 March
0
3.0
1 3 March
2
-7
-7
-6
14 March
0
-5
8.1
1 5 March
0
-4
15.2
16 March
2
-3
5.3
For a few days previous t o 16 March r a i n f e l l on Granite Mountain
on a number o f occasions and formed a n i c e l a y e r on t h e lower mountain
and a l i g h t c r u s t on t h e upper mountain. Overnight, from 15 March t o
t h e e a r l y morning o f t h e 16th, l i g h t , d r y snow f e l l , becoming more
moisture-laden through t h e morning of t h e 1 6 t h . By mid-morning over
30 cm o f new snow had accumulated. Around noon on 16 March w e s t e r l y
winds w i t h estimated speed 30-50 km/h were observed above t h e 1500 m
l e v e l . Unsettled, cloudy weather p r e v a i l e d i n t h e e a r l y a f t e r n o o n .
ACCI DENT SUMMARY
Granite Mountain was n o t open f o r s k i i n g on 15 March. On 16 March,
a t approximately 1400 h, t h r e e s k i e r s e n t e r e d t h e s t e e p c h u t e s j u s t
above t h e Squaw Basin. Numerous chutes and g l a d e s e x i s t i n t h i s a r e a
and a number o f t r a c k s had been l a i d p r i o r t o t h e passage of t h e p a r t y
i n question.
A s t h e group s k i e d down, a s l a b avalanche r e l e a s e d and caught them.
One woman was c a r r i e d down through t h e narrow, s t e e p chute and p a r t i a l l y
b u r i e d . She was s e v e r e l y i n j u r e d , coming t o r e s t a g a i n s t a t r e e . The
second s k i e r was s t r u c k by a windmilling s k i d u r i n g t h e avalanche and
r e c e i v e d f a c i a l l a c e r a t i o n s , b u t was n o t b u r i e d . The t h i r d p a r t y member,
a young g i r l , s u s t a i n e d an i n j u r e d knee.
RESCUE
Because t h e p a r t y members were i n varying s t a t e s of i n j u r y and shock,
t h e immediate r e s c u e e f f o r t s were confused. The s k i e r who had s u s t a i n e d
f a c i a l i n j u r i e s skied t h e t r a v e r s e t o t h e b a s e s t a t i o n of t h e s k i a r e a
where he r e p o r t e d t h e a c c i d e n t . The s k i p a t r o l then proceeded up t h e
c h a i r l i f t and t o t h e a c c i d e n t s i t e . Approximately 2 h a f t e r t h e a c c i d e n t
t h e i n j u r e d s k i e r s were brought by oversnow v e h i c l e t o t h e base s t a t i o n .
The a c c i d e n t occurred i n t h e same a r e a a s t h e f a t a l one on 2 3
December 1971. Although t h e Squaw Basin i s beyond t h e s k i a r e a boundary,
i t i s a popular powder s k i i n g a r e a . I t i s d i f f i c u l t t o decide whether
such a r e a s , e a s i l y a c c e s s i b l e from t h e l i f t terminal, should b e closed t o
s k i e r s , c o n t r o l l e d , o r marksd with warning s i g n s only. I n any case, t h e
s k i p a t r o l must be aware o f hazardous conditions and b e prepared f o r
rescue i n t h e s e a r e a s o u t s i d e t h e r e g u l a r s k i r u n s . Caches with rescue
equipment should b e maintained a t t h e t o p of t h e l i f t s .
RED MOUNTAIN, ROSSLAND, B .C.
16 MARCH 1975
One s k i e r b u r i e d
WEATHER
Weather observations a t t h e Rossland MacLean S t a t i o n a r e l i s t e d
under t h e accident a t Granite Mountain on t h e same day. Red Mountain i s
j u s t adjacent t o Granite Mountain and experienced t h e same i n t e r m i t t e n t
r a i n s i n t h e days p r i o r t o 16 March. A strong i c e c r u s t was formed on
t h e lower mountain, covered by 30-35 cm of new snow.
ACCIDENT SUMMARY
A t about 1600 h, 16 March, a p a r t y of s i x s k i e r s decided t o make
t h e l a s t run down t h e south s i d e of Red Mountain. The a r e a i s
permanently closed because o f t h e hazard of deep mine p i t s , b u t it is
o f t e n s k i e d by l o c a l s . After descending through t h e mine p i t a r e a t h e
group came t o t h e l a s t p i t c h , a smooth open mine t a l u s s l o p e above t h e
road back t o town. The group broke up t o descend t h e untracked powder.
The f i r s t s k i e r c u t a c r o s s t h e s l o p e above a s l i g h t hollow a t t h e
l e e s i d e o f a s p i t of t r e e s , then turned down t h e f a l l - l i n e , f a i l i n g t o
n o t i c e t h a t he had s t a r t e d a small avalanche. Overtaken by t h e moving
snow, he was c a r r i e d t o t h e bottom of t h e slope and completely b u r i e d when
t h e avalanche came t o r e s t . Fortunately he was a b l e t o move one hand
and t o shake i t f r e e above t h e deposited avalanche snow.
RESCUE
The r e s t of t h e group s k i e d immediately t o t h e deposition area,
discovered t h e s i n g l e protruding hand and dug o u t t h e i r uninjured
companion.
AVALANCHE DATA
The avalanche f r a c t u r e d t o a depth o f 40 cm and obviously contained
dry new snow above t h e i c e c r u s t . I t r e l e a s e d a t an a l t i t u d e of
approximately 1275 m and f e l l about 100 m v e r t i c a l l y . The aspect of
t h e s l o p e i s south and t h e g r a d i e n t about 35 deg. The avalanche
deposited loose snow with an average depth o f about 1.6 m.
COMMENT
Experienced s k i e r s , t h e group should have recognized t h e danger of
t h e new snow overlying a n i c e c r u s t , b u t a s so o f t e n b e f o r e t h e a t t r a c - t i o n o f untracked powder p r e v a i l e d . This s k i e r was f o r t u n a t e n o t t o
share i n j u r i e s o r worse with s k i e r s caught i n t h e avalanche a t Granite
Mountain 2 h e a r l i e r .
14 JANUARY 1976
One tobogganer k i l l e d , one r e s c u e d unharmed
LOCATION
Cap Santg i s 25 m i l e s southwest of Qugbec C i t y on t h e S t . Lawrence
River, and i s 80 m above s e a l e v e l .
WEATHER
Observations a t Qugbec A i r p o r t , 74 m ASL
Temperature
Precipitation
O c
Date
Max
10 January
-18.5
11 January
-19.5
12 J a n u a r y
- 16
- 9.5
- 4.5
13 January
14 January
M in
mm
- 30
- 34
T
-21.5
0.8
-21
2.3
-12
15.0
T
Heavy snowfall d e p o s i t i n g 17 cm of new snow was followed by f i n e
weather on t h e a f t e r n o o n o f 14 January.
ACCIDENT SUMMARY
Late i n t h e a f t e r n o o n two young boys were tobogganing on a s t e e p ,
snow-covered h i l l n e a r one of t h e i r homes i n Cap Sant6. I t i s b e l i e v e d
t h a t d u r i n g a descent they were engulfed by moving snow and subsequently
b u r i e d under s e v e r a l f e e t of i t . The a c t u a l time o f t h e occurrence i s
unknown a s t h e a c c i d e n t was unobserved.
RESCUE
An e x t e n s i v e s e a r c h was i n s t i t u t e d by l o c a l p o l i c e and c i t i z e n r y a t
about 1700 h . A f t e r about 1 h t h e v i c t i m s were discovered, b u r i e d under
about 2 m o f snow. One was rescued uninjured, b u t h i s companion was
found unconscious and n o t b r e a t h i n g ; a l l a t t e m p t s t o r e v i v e him were
f r u i tless.
AVALANCHE DATA
The avalanche f e l l about 60 m v e r t i c a l l y over a width of 7 t o 10 m,
d e p o s i t i n g snow up t o 3 m deep. The s l o p e was considered t o b e q u i t e
s t e e p and o f s o u t h e r l y exposure.
COMMENT
Twenty y e a r s e a r l i e r t h e same t y p e o f a c c i d e n t occurred i n e x a c t l y
t h e same l o c a t i o n . Although avalanches a r e r a r e i n E a s t e r n Canada, t h i s
and o t h e r a c c i d e n t s show t h a t t h e p o s s i b i l i t y should n o t b e discounted.
..
KOOTENAY PASS, CRESTON, B C
16 JANUARY 1976
Three occupants o f a v e h i c l e k i l l e d , two rescued unharmed
WEATHER
Observations a t Kootenay Pass, 1770 m ASL
Temperature
OC
Date
Time
12 January
0700
1600
- 9
13 January
14 January
Max
New Snow
Min
cm
- 9.5
9
5
8
0700
1600
-
8
-12
- 9.5
- 14
- 15
0700
1600
-
8
- 14
15 January
0700
1600
-
16 January
0700
1
1600
3
- 5.5
3.5
1.5
-
Rain
mm
1
8
10
6
6
3.5
20
2
1.5
1
5
(approx)
1
A l i g h t r a i n s t a r t e d a t 2130 h on 15 January and t h e temperature
reached o O C a t 0200 h on t h e 1 6 t h . Between 0200 and 0700 h and a g a i n a t
1115 h on t h e 1 6 t h s e v e r a l small avalanches r a n t o t h e highway on t h e
e a s t s i d e o f Kootenay Pass, an a r e a known f o r f r e q u e n t small avalanches.
The highway was c l o s e d i n t e r m i t t e n t l y , and opened a t 1130 h .
ACCIDENT SUMMARY
S h o r t l y b e f o r e noon on 16 January f i v e people were t r a v e l l i n g west
i n a c o n v e r t i b l e c a r on Highway 3. Without warning, 2 km west o f t h e
summit o f Kootenay Pass, an avalanche swept t h e moving v e h i c l e from t h e
road and c a r r i e d it down t h e s t e e p , long embankment. I t came t o r e s t
a g a i n s t t h e f i r s t t r e e s i n t h e run-out zone, b u t t h e c o n v e r t i b l e o f f e r e d
l i t t l e p r o t e c t i o n and a l l f i v e were thrown o u t .
RESCUE
Another v e h i c l e t r a v e l l i n g i n f r o n t o f t h e c o n v e r t i b l e narrowly
escaped t h e avalanche and continued westward. Encountering p o l i c e , t h e
d r i v e p r e p o r t e d t h e avalanche and h i s s u s p i c i o n t h a t one o r more v e h i c l e s
following might have been caught. The p o l i c e o f f i c e r immediately
proceeded t o t h e s i t e . A t t h e same time a n o t h e r v e h i c l e t h a t had been
following t h e b u r i e d c a r had stopped a t t h e avalanche d e p o s i t on t h e
road, turned back, and r e p o r t e d t h e a c c i d e n t a t t h e highway maintenance
e s t a b l i s h m e n t a t t h e summit a t about 1155 h .
S h o r t l y a f t e r 1200 noon t h e r e s c u e organized by t h e highway
maintenance s t a f f was under way. The f i r s t e i g h t men a t t h e a c c i d e n t
s i t e began probing t h e snow on t h e r o a d . Fog d i d n o t permit a f u l l
assessment of t h e d e p o s i t i o n a r e a below t h e highway, b u t when more
r e s c u e r s a r r i v e d two men walked down t h e s t e e p s l o p e f o r a s e a r c h of t h e
lower d e p o s i t i o n a r e a . One of them discovered a magazine l y i n g on t h e
snow n e a r t h e t o e o f t h e most e a s t e r l y d e p o s i t , and s h o r t l y afterwards,
a t approximately 1315 h, a l e g was discovered p r o t r u d i n g from t h e snow.
The r e s c u e r s immediately dug o u t a young woman whose head was b u r i e d
about 1 m below t h e s u r f a c e . She was conscious and a b l e t o inform t h e
r e s c u e r s o f h e r f o u r companions.
A d d i t i o n a l personnel were c a l l e d down from t h e highway. Random
probing n e a r t h e l o c a t i o n o f t h e f i r s t v i c t i m r e v e a l e d a young c h i l d
b u r i e d nearby under 1.2 m o f snow. No s i g n s o f l i f e were v i s i b l e b u t
a f t e r a r t i f i c i a l r e s p i r a t i o n was administered t h e c h i l d recovered. A t
t h e same time, a t approximately 1430 h, two o t h e r v i c t i m s were discovered
nearby, 0.6 t o 1 m below t h e s u r f a c e . E f f o r t s a t r e s u s c i t a t i o n were
u n s u c c e s s f u l . A t approximately 1500 h t h e l a s t v i c t i m was found w i t h
h e r head approximately 1.6 m below t h e s u r f a c e . Attempts a t
r e s u s c i t a t i o n were, however, u n s u c c e s s f u l . The two s u r v i v o r s were
evacuated t o Nelson by h e l i c o p t e r .
The remainder o f t h e avalanche d e p o s i t was t h a n checked f o r o t h e r
v e h i c l e s and an R .C . M . P . dog searched f o r f u r t h e r v i c t i m s .
AVALANCHE
The s l a b avalanche f r a c t u r e d 80 cm deep on a bed of an i c e c r u s t
o v e r l a i n by s u r f a c e h o a r ( s e e Figure 33). The c r u s t was t h e r e s u l t of
r a i n e a r l y i n December, and t h e s u r f a c e h o a r had formed i n c l e a r weather
between 5 and 15 December. Snowfall on 14 and 15 January, r a i n , and a
high temperature probably t r i g g e r e d t h e deep u n s t a b l e snow.
The avalanche s t a r t e d on a n open, s o u t h - f a c i n g s l o p e w i t h a n
i n c l i n a t i o n o f 40 deg a t e l e v a t i o n 1825 m, about 200 m h i g h e r than t h e
highway. Damage t o t r e e s and snow packed a g a i n s t them i n t h e run-out
zone demonstrated t h a t t h e avalanche had a c o n s i d e r a b l e dry powder
component, b u t t h e snow d e p o s i t e d on t h e highway and below had a wet
appearance and would p o i n t t o a wet flowing component.
The avalanche had a t o t a l volume o f 28 000 m3 of snow.
a 300 m l e n g t h o f highway w i t h a depth up t o 3.5 m.
I t covered
Deep weak l a y e r s i n t h e snowcover such a s c r u s t s and s u r f a c e hoar
can produce unexpected, l a r g e avalanches. The a b i l i t y t o recognize deep
i n s t a b i l i t i e s through continuous o b s e r v a t i o n o f t h e snowcover makes t h e
d i f f e r e n c e between an avalanche a n a l y s t and t h e c a s u a l snow and
avalanche observer, b u t p r e d i c t i o n o f t h e time when a n avalanche w i l l
s t a r t n a t u r a l l y a s a r e s u l t o f a deep i n s t a b i l i t y i s d i f f i c u l t even f o r
a s k i l l e d person. An u n s t a b l e c o n d i t i o n may p r e v a i l f o r s e v e r a l weeks
without producing avalanches and r a p i d l y change t o c r i t i c a l w i t h a
snowfall, s t r o n g wind, o r high temperatures.
The c l o s u r e o f a highway f o r long p e r i o d s o f time may be impossible
when u n s t a b l e snow c o n d i t i o n s p r e v a i l , and i t would t h e r e f o r e b e
n e c e s s a r y t o c o n t r o l avalanches e i t h e r by e x p l o s i v e s o r o t h e r means,
Experience has shown t h a t when a deep s l a b i n s t a b i l i t y e x i s t s e x p l o s i v e s
must b e a p p l i e d r e p e a t e d l y w i t h v a r i a b l e charges, a t d i f f e r e n t l o c a t i o n s ,
and whenever t h e weather changes, u n t i l t h e u n s t a b l e snow i s removed i n
a l l t h e a v a l a n c h e - s t a r t i n g zones. A f u l l c o n t r o l program might have
prevented t h e a c c i d e n t , b u t i n t h e w i n t e r 1975-76 t h e avalanche c o n t r o l
program a t Kootenay Pass was l i m i t e d owing t o a s h o r t a g e of a r t i l l e r y
p i e c e s and f i x e d gun emplacements.
Because t h e a c c i d e n t was observed, t h e avalanche s i t e c l o s e t o t h e
highway maintenance establishment, and t h e maintenance s t a f f t r a i n e d and
equipped f o r avalanche rescue, an organized s e a r c h was i n i t i a t e d w i t h i n
a very s h o r t time. Unfortunately, f o g and s t e e p t e r r a i n delayed t h e
s e a r c h i n t h e run-out zone below t h e highway, and t h i s r e s u l t e d i n a
long b u r i a l time f o r t h e v i c t i m s . Both c a r and v i c t i m s were found n e a r
t r e e s , which a g a i n proved t o b e l i k e l y b u r i a l s p o t s .
SNC
~~~!!MENI
F i g u r e 32
Avalanche s i t e , Kootenay P a s s , km 2 w e s t , 16 J a n u a r y 1976
(Photo c o u r t e s y B r i t i s h Columbia M i n i s t r y o f Highways and
P u b l i c Works)
TEMPERATURE,
-10
Figure 33
-5
O C
0
Snow p r o f i l e a t f r a c t u r e l i n e ,
Kootenay Pass, 19 January 1976.
PARADISE BASIN, INVERMERE, B . C .
23 MARCH 1976
One s k i e r k i l l e d , two s k i e r s i n j u r e d
WEATHER
Tuesday, 23 March was a sunny day w i t h l i g h t winds and a temperature
of -5OC. No avalanche a c t i v i t y was noted i n t h e a r e a . Depth h o a r had
been observed throughout t h e w i n t e r i n t h e e a s t e r n P u r c e l l Mountains.
ACCIDENT SUMMARY
' h o p a r t i e s o f nine, each w i t h a guide, were s k i i n g i n P a r a d i s e
Basin s h o r t l y a f t e r lunch on 23 March, each s k i e r c a r r y i n g an avalanche
r e s c u e t r a n s c e i v e r . The groups had been flown t o t h e summit by h e l i c o p t e r and t h e intended r o u t e from t h e l a n d i n g a r e a l a y o v e r t h e south
r i d g e . Guide 1 took h i s p a r t y down a wind r i d g e t o t h e e a s t o f t h e
main s l o p e , and a f t e r s k i i n g most o f t h e way they r e s t e d on a k n o l l n e a r
t h e bottom. Guide 2 s k i e d d a r n 15 o r 20 m west o f group 1, stopped and
i n s t r u c t e d h i s s k i e r s t o come down i n s i d e h i s t r a c k , two a t a time.
A f t e r t h e f i r s t p a i r had made a few t u r n s and t h e second was s t a r t i n g
t h e whole b a s i n f r a c t u r e d . Guide 2 gave a warning over t h e r a d i o t o
Guide 1 who saw t h e avalanche coming w i t h two s k i e r s b e i n g f l i p p e d
through t h e s t e e p rocky a r e a i n mid-slope.
RESCUE
When t h e avalanche stopped, Guide 1 i n s t r u c t e d h i s p a r t y , who were
untouched, t o w a i t on t h e k n o l l w h i l e h e climbed t o two s k i e r s h e could
s e e p a r t l y b u r i e d on t h e avalanche d e p o s i t .
He found t h e lower one i n j u r e d , a l t h o u g h n o t immediately endangered,
and climbed q u i c k l y t o t h e second s k i e r who was a l s o i n j u r e d . I n t h e
meantime, Guide 2 had made a headcount and found a t h i r d s k i e r missing.
By r a d i o h e n o t i f i e d Guide 1, who immediately switched h i s r e s c u e
t r a n s c e i v e r t o r e c e i v e and s t a r t e d t o t r a v e r s e down, p i c k i n g up a s i g n a l
w i t h i n a couple o f t r a v e r s e s .
A s he was determining t h e e x a c t p o i n t o f b u r i a l , two o t h e r guides,
who had observed t h e a c c i d e n t from t h e a i r , a r r i v e d w i t h probes and
s h o v e l s . The b u r i e d s k i e r was l o c a t e d w i t h a probe, h i s head was
uncovered, and about 10 min from t h e time o f t h e a c c i d e n t mouth-to-mouth
r e s p i r a t i o n was s t a r t e d . Once t h e v i c t i m was f r e e d from t h e snow a
d o c t o r from t h e s k i group attempted cardiopulmonary r e s u s c i t a t i o n , b u t
a f t e r about 20 min w i t h n e g a t i v e r e s u l t s t h e d o c t o r advised t h a t t h e r e
would b e no p o i n t i n continuing. I t was l a t e r determined t h a t t h e
v i c t i m had d i e d o f head i n j u r i e s . The two i n j u r e d s k i e r s were flown t o
the hospital i n Invemere.
AVALANCHE
The avalanche r e l e a s e d a t a n a l t i t u d e o f 2550 m y w i t h a f r a c t u r e
l i n e 60 cm deep running o v e r 1000 m around t h e b a s i n . The f i r s t s k i e r ,
Guide 2, d i d n o t t r i g g e r t h e avalanche, and o n l y t h e combined weight of
s e v e r a l s k i e r s s t a r t e d i t . I t r a n on a s o u t h - f a c i n g s l o p e of over 400 m
v e r t i c a l drop, w i t h a n i n c l i n e i n t h e s t a r t i n g zone o f 28 deg i n c r e a s i n g
t o 45 deg i n t h e rocky a r e a . This d r y s l a b avalanche f r a c t u r e d on an
i n t e r n a l l a y e r and moved q u i c k l y o v e r t h e s u r f a c e . About 100 m from t h e
t o p of t h e s l o p e o n l y a l i g h t snowcover w a s l e f t . A f t e r t h e avalanche
had o c c u r r e d t h e d e b r i s was hard and f i r m by t h e time t h e body was f r e e d .
COMMENT
The depth and s t r e n g t h o f t h e snow pack v a r i e d g r e a t l y throughout
t h e b a s i n . The e a s t e r n s i d e r e c e i v e d wind-transported snow. Group 1
s k i e d on t h e wind-exposed r i d g e and Group 2 i n t h e a r e a where d r i f t i n g
snow was d e p o s i t e d .
ERS
1
Figure 34
Sketch o f avalanche a t P a r a d i s e Basin,
Invermere, B.C . , 23 March 1976
TEMPERATURE,
Figure 35
O C
Snow p r o f i l e a t f r a c t u r e l i n e 50 m
below t h e t o p , P a r a d i s e Basin,
24 March 1976.