HISTORICAL NEWS SEARCH - Government of British Columbia

January 1 and 6-15, 1996
Event type: Rain-on-snow flooding and debris slide.
Precipitation: Terrace A (48.2 mm/1 day), January 1, 1996; Terrace A (145.8 mm/7 days), January 6-12, 1996.
Source: The Terrace Standard, January 10, 1996; The Daily News, January 15, 1996; Lakes District News, January 17,
1996; British Columbia Report, January 29, 1996; Len Barak, Ministry of Environment Lands and Parks, pers. comm.;
CBC newscasts, January 11 and 12, 1996.
Early January, two rain and/or snow events took place in the Terrace area. Unseasonable warm weather with
rain and a melting snowpack caused flooding and avalanches. Heavy rain occurred in north coastal British Columbia
with heavy snow in the Stewart area.
On January 1, the Terrace airport recorded 48.2 mm precipitation, which included 33.2 cm of
snow. For three or four hours, the snow came down at a rate of 4 cm per hour. (The Terrace Standard, January 10,
1996). On January 10, the Shames Mountain ski hill recorded over 100 cm of snow in 24 hours. Because of the
avalanche danger, the Ministry of Transportation and Highways closed the road to the ski hill for two days. Between
January 7-13, about 2 m of snow fell on Stewart. For four days starting January 10, snowdrifts up to 4 m deep and 100
m long covered the highway at Bear Pass, 25 km. east of town. This prompted the Ministry of Highways to close
Highway 37A, the only land route in and out of town, for four days. *1) Highway crews feared that, even if they
cleared the route, avalanches might cover the road again. Due to a high avalanche danger, Highway 37 was closed
between Bell II-Bob Quinn. During the snowfall, the local airstrip was closed as well.
On January 13, a washout 15 mi. (24 km) east of Terrace put the rail track out of commission for about 24
hours. Train traffic was interrupted and VIA Rail passengers were bussed between Smithers-Prince Rupert on January
13 and 14. The slide was the first traffic interruption on the British Columbia north line for several years (The Daily
News, January 15, 1996).
During January 12-13, two debris flows from unlogged gulley systems hit the Shannon Mainline, located a
short distance up the Skeena from Terrace. On January 12, Terrace airport 15.8 mm of rain melted the 29-cm
snowpack. Given that the preceding four days were warm and wet, it is reasonable to assume that the snowpack had at
least 30% water equivalent. Thus the minimum total water on January 12 was 15.8 mm plus 87 mm = 102.8 mm, or a
return period of approximately 20 years. The maximum water content for the snowpack could have been 39%,
recorded on December 30, 1992 at the Terrace airport. Thus the maximum total water on January 12 could have been
15.8 mm plus 113.1 mm = 128.9 mm or a return period of approaching 100 years. (Len Barak, pers. comm.).
In the Francois Lake-Ootsa Lake area, unusually heavy snow combined with poor design in some cases
caused the roofs of at least seven buildings to collapse. Between January 13-14, five structures (hay barns), one shop
and one of undetermined nature came down. Building inspector Wainwright came close to issue a snow advisory,
which he did do when about 20 roofs collapsed in February and March 1994. On that occasion, however, mild
temperatures and heavy rain had swept through the area.
Bella Coola recorded some 200 mm of rain in 36 hours. On January 11 and 12, schools were closed due to a
possible flooding threat. Provincial Emergency officials issued a flood alert, warning Bella Coola residents to be ready
to move to higher ground.
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*1) The last time Stewart residents faced a four-day road blockage was in 1989. Mayor Andy Burton suggested that the
ministry boost funding to keep the highway open, or install fixed gun mounts for mortars to clear snow from
mountainsides (British Columbia Report, January 29, 1996).
1996
Event type: Dam burst flooding.
Precipitation: Not applicable.
Source: Letter December 3, 1996 to Helmut Hemmel Ministry of Environment, Lands and Parks file D620198/Frame
Creek Dam 6000437.
Sometime in 1996, a dam failure occurred on Frame Creek. During the construction,
earthfills were likely too great for the compaction equipment. Tracked equipment like bulldozers, though they are
heavy, their weight is dispersed upon its track, resulting in less than optimum compaction. Evidence also suggested
that the slopes of the dam were too great for soil conditions.
Upon reservoir filling, beaver activity plugged the inlet of the spillway raising water levels. High watermark
suggests freeboard was dramatically reduced and threatened overtopping. Saturation of the downstream slope occurred
and it began to slough. The 20-cm outlet sluice was opened to drain the reservoir, which took three to four weeks. The
saturated upstream slope failed and sloughed into the reservoir, damaging the gates and possibly the intake.
Mid February 1996
Event type: Flooding.
Precipitation: Not available.
Source: The Terrace Standard, February 21, 1996.
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