HISTORICAL NEWS SEARCH - Government of British Columbia

Source: Northern Sentinel, February 21, 1985; The Interior News, February 27, 1985; Jamieson and Geldsetzer 1996
(p. 109; pp. 169-170); B.C. Ministry of Transportation and Highways 1980; Adam Charneski, pers. comm. July 1991,
Line Foreman Alcan, Kitimat.
At slide path Rockface, 69.6 km west of Terrace on February 18, a CNR train ran into a slide deposit at 50
mph (80 km/h). The lights on the engine were broken and the train uncoupled.
An avalanche wiped out a transmission tower between Kemano-Kitimat near the Kildala Pass, 24 km from
Kemano on the south side of the Hanging Valley. *1) The slab type avalanche occurred at a steep 60% slope at the
6,000 ft. (1,800 m) level. It jumped a ridge and spilled over and the windblast created by the massive snow flow
knocked down the aluminum tower 124L. Pieces of the tower were carried away over a maximum horizontal distance
of 950 ft. (285 m). The windblast also caused minor damage to steel members of adjacent towers 123R and 124R at an
elevation of 740 m and knocked down trees on the uphill side of these towers (A. Charneski, pers. comm.). The single
curcuit on the right was able to maintain the delivery of power. *2)
In the five days prior to the avalanche, about 200 mm of precipitation had fallen in the area. This and
previous snowfalls probably an approximately 190-cm deep unstable snowpack in the avalanche path. The avalanche
starting zone, at 1,700 m, was on a northeast-facing slope with a 39 o incline and lee to the prevailing storm wind. After
running down an open 31 o slope, the avalanche was deflected by a 50-m high ridge. It then moved over 400 m on
gentle incline between 0-10 o along the opposite valley side, towards the powerline.
Models of avalanche dynamics and the runout distance of the avalanche led to the conclusion that the
avalanche speed at tower 124L was approximately 24 m/s (86.4 km/h). The avalanche snow was dry and probably had
a deep powder component. The age of broken threes in the avalanche path suggested that an avalanche of similar
magnitude had not occurred for close to 100 years. (Peter Schaerer In: Jamieson and Geldsetzer 1996).
On February 22 at midnight, an avalanche on Onion Mountain near Smithers killed a snowmobiler. At just
after midnight, it was snowing heavily. A number of snowmobilers were taking turns running up of one of its slopes.
The victim, a 29-year old man, started up the slope and was traveling at high speed when hit by the avalanche. The
slide was about 350 m wide and ran 400 m. Neither the victim nor his snowmobile were buried in the avalanche. But
when the other members of the group found him, he had died of massive trauma. (Jamieson and Geldsetzer 1996).
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*1) For a distance of 15 km over Kildala Pass, the transmission line is split into two single, parallel circuits. The line
on the right side (identified by R) is carried on steel lattice towers, and the line on the left (L) on towers built with
aluminum tubing. The transmission line has a history of destructive avalanches. By January 26, 1955, avalanches had
already destroyed three towers in Glacier Bowl at the south side of Kildala Pass on the line completed only the
previous year. (Jamieson and Geldsetzer 1996).
*2) In the following years, earth and steel deflectors were built at other exposed towers. On January 22, 1973, an
avalanche destroyed tower 105L. Subsequently, placing strong steel breakers in front of them protected the legs of
towers 105L and 105R. On December 27, 1992, tower 113R near the top of Kildala Pass was damaged. (Jamieson and
Geldsetzer 1996).
March 1985
Event type: Landslide potential.
Precipitation: Not applicable.
Source: Times Colonist, March 12, 1985.
In March, Dinosaur Lake on the Peace River was closed to the public until further notice for all recreation
and sport fishing. This followed a study on the movement of a landslide, which developed on the north-shore of the
reservoir near the town of Hudson’s Hope. The slide had moved 5 m in the last four years. It was feared that if it would
move rapidly into the water it could create waves in excess of 4 m. Depending on how fast the slide would move, the
lake could be closed for up to five years.
September 3-4, 1985
Event type: Flooding.
Precipitation: Prince Rupert M. Circ (57.4 mm/1 day), September 3, 1985; Prince Rupert A (52.2 mm/1 day),
September 4, 1985.
Source: The Daily News, September 12, 1985.
Unusually heavy rains washed out the forms for the construction of the new Wolf Creek dam near Port
Edward. Forms for the 5-m high and 13-m wide concrete dam had been set up and crews were ready to pour the
concrete when the washout occurred. The forms lifted up and drifted against a tractor. Stikine Construction company
lost about 62 man-hours as a result of the incident. Work on the project resumed on September 12.
September 19-20, 1985
Event type: Debris slides.
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