For many years, this area was considered by Juneau residents almost on a par with the Nenana ice breakup and some informal betting took place as to which month and day between Nov. 30 and May 1 (an avalanche) would happen. It was generally recognized that at least one would occur each year.
I have lived in Juneau for 83 years and through that period have witnessed many snow and earth avalanches in the Gastineau Channel and Glacier Highway regions.
I have spent a great deal of time compiling statistics on this subject. Plus meeting with the state Department of Transportation personnel and have drawn some scary conclusions.
My main focus for this study has been the Thane Road area. The Department of Transportation has a comprehensive report dated December 1990, Phase 1, and 1991, Phase 2. These reports were done by Doug Fesler and Jill Fredston of the Alaska Mt. Safety Center Inc. and Art Mears of Arthur I. Mears Inc., of Gunnison, Colo. I have met Mr. Mears and his wife and am impressed by his background, especially as it pertains to snow avalanches.
These experts have classified names on the three paths of the Thane avalanche activity such as Snowslide Creek (commonly referred to for many years as Snowslide Gulch). This path is by far the greatest concern, showing extensive activity in 66 occurrences from available, but incomplete date, from 1891 to 1989. For many years, this area was considered by Juneau residents almost on a par with the Nenana ice breakup and some informal betting took place as to which month and day between Nov. 30 and May 1 these events would happen. It was generally recognized that at least one would occur each year.
The No. 2 path is referred to as Cross Bay, which has had 14 occurrences. No. 3 path is called Middle Path, with five occurrences.
The statistics show 20 avalanches with no path designation, but it is fair to say the bulk of those were in Snowslide Gulch, which would bring the total up to a minimum of 72.
With all this in mind, focus has to center on the best way to mitigate this area first, and I believe a snowshed is by far the most sensible method.
Among the partial effects of this activity were: Three people killed; one person nearly being swept into Gastineau Channel (I knew him personally); three cars and/or personal equipment swept into the channel; 10 times electric power was interrupted and power lines damaged; road blocked 87 times.
No complete record was kept of the hours or days people were prevented from their normal activities, but all indications point to this being a very substantial figure.
In order to realize the actual exposure for passengers to either death or injury, the following figures provide some idea based on a five-month winter average:
834 vehicles use this road area daily (on average).
25,020 represents one month total vehicles.
125,100 represents five months of exposure for a single passengers.
600 bus students (included in the figures above for five months).
(Using one and a half passengers per vehicle might be a more realistic figure and result in a larger total. All the figures shown are based on traffic in each direction.)
The extensive research done by the professionals reveals that a properly built and lighted snowshed installed at the Snowslide Gulch is the most life-saving method. When this area is compared to the Seward Highway, one glaring difference exists in that deep water borders the Thane area as opposed to mud flats up north. With so many avalanches reaching out into the water, that alone provides a double chance of death to those involved.
No satisfactory substitute really exists to protect those in vehicles and those using heavy equipment to clear the road. There is no doubt that such an installation is expensive, but it will provide the Department of Transportation first-hand experience and win the support of any such methods for future roads and highways.
Such support should originate with the good people living in Thane and those people living in the Juneau area who use this road.
As it takes years to move this kind of project into realization, it is extremely important a start is made. The timing is now.
As of this winter, Bill Glude, an avalanche expert, will be working with the weather bureau for forecasting and instructing interested citizens regarding avalanche hazards. The Department of Transportation will appreciate this addition, but all of Juneau has to get behind these endeavors in order to achieve a place on the state priority list of road projects.
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