WhiteCAP_Plan_01SEPT..

NCE WhiteCAP Environmental History
Other examples of the damage caused by problematic snowmelt can be found in 3.2.2.
The remainder of this section describes the impacts of snow itself.
Structural damage due to heavy snow loads occurred in April 1954 when a large snow
slide off the roof of the Civic Center damaged a part of the building. The heavy snow
load also forced the walls out of line and destroyed the windows. The cost of the
damage was about $3,000 ($24,425.53 2009 adjusted value). In October 1968, newly
fallen snow caused a number of motor vehicle accidents. The same conditions occurred
again in November 1968, which was the first time that the airport runways were closed
due to heavily falling snow. In December 1980, Whitehorse missed a record snowfall by
only two inches (the record was set in 1967 with a snowfall of 272 mm). Snow clearing
crews worked non-stop on Christmas day to clear the road to the hospital and the priority
streets in the downtown. Nine minor accidents occurred regardless.
The late 1980’s and 1990’s are seemingly marked by a considerable change in the
amount of snowfall in the Whitehorse area. The record for snowfall was broken several
times over this period, causing localized damage around the city. For example, a
significant amount of snow fell on Whitehorse in September 1986, which far surpassed
the normal monthly total snow water equivalent for that month. The mix of snow and
freezing rain created dangerous driving conditions, compounded by driver error. In at
least one case a resident failed to properly clear their vehicle windows and accidentally
backed into another vehicle. In the case of this storm, public warnings constituted the
community response. City crews were unable to keep up with the snow clearance levels
that the storm demanded, which resulted in poor driving conditions on the highway. City
crews subsequently warned residents against using the highway if it wasn’t necessary.
At this time, the highway to Carcross was still under renovation which further increased
the infrastructure stress. The 1986 storm set a record for precipitation with 67.2 mm of
snow and rain. About 53.9 mm of precipitation fell in 4 days, 2.2 mm fell as rain with
another 31.4mm falling as snow.
In December 1991, the 1986 snowfall record was broken with 677 mm. The city
experienced high snow fall again in 1992; the warm wet snow dump caused an
afternoon blackout for 1000 people living between McCrae and Teslin. Moist snow had
fallen onto an insulator, which then broke off an electrical pole near Miles Canyon,
resulting in a short. A diesel generator was used to provide power for the Teslin area
until the damage could be repaired. Three megawatts of power were lost in the blackout.
In the same storm the weight of 300 mm of snow caved in the roof of a vehicle.
In February 1996, a combination of mild weather and high winds resulted in a heavy
snowfall that caused trees to snap and fall on power lines. Problems reportedly began at
the Robinson subdivision and then expanded to include Annie Lake, Cowley Creek and
Horse Creek. Residents became frustrated as they lost power. The damage was so
extensive that ultimately the electric company opted to wait for temperatures to rise to
5°C and melt the ice and snow along power lines. As a result of this incident, Yukon
Electrical installed a breaker that would allow isolation of a particular subdivision in the
event that repairs would have to be made. Breakers are standard across the territory
such that power outages due to repairs are limited to particular areas.
D.14