Item: 2007 winter avalanches on the kemano kitimat powerline
Title: 2007 winter avalanches on the kemano kitimat powerline
Proceedings: Proceedings Whistler 2008 International Snow Science Workshop September 21-27, 2008
Authors: Rod Gee, Chris Stethem, Alan Jones, Kevin Fogolin, Mike Gajda.
Abstract: 2006-2007 was a 100-year winter on British Columbia's North Coast. Forty of seventy-two towers in Powerline Pass of the Rio Tinto Alcan Kemano-Kitimat powerline, completed in 1954, are exposed to destructive avalanches. On March 28th a storm deposited over 100 mm of precipitation in 24 hours resulting in several large destructive avalanches. Tower 113R on the south side of Powerline Pass was destroyed for the second time in 15 years. Ten kilometers to the south an avalanche in path Ke 8 jumped from its usual track into the adjacent Ke 9 path clearing a swath of mature timber down to the defensive splitter at Tower 39. This paper will describe the destructive effect of large, long return period avalanches and the reconstruction project which required an intensive program of hazard evaluation and avalanche control.
Presenters: Rod Gee.
Keywords: avalanche control, mitigation, return period