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John Stimberis - Personal Communication
Conversation during Chinook Pass avalanche control work, 18 May 2009
On May 18, 2009, I accompanied John Stimberis and Aaron Opp during their avalanche control work on skis while preparing to open Chinook Pass for the summer. I carried a digital voice recorder and used it intermittently. I also jotted down notes on paper. This summary draws from both sources.
by Lowell SkoogJohn Stimberis took up skiing on Mt Hood in high school. He went to college at Central Washington University and started skiing at Alpental. After college he got full-time jobs with both the Alpental ski patrol (in winter) and the U.S. Forest Service as a wilderness ranger (in summer). In his late twenties, he applied for an avalanche forecaster job with WSDOT. He worked on the Chinook Pass opening for the first time during the big snow year of 1999. He has been working year-round for the WSDOT avalanche control program since 2006. He is currently 40 years old.
Snoqualmie Pass Avalanche Work
In winter, six avalanche forecasters work at Snoqualmie Pass, three on the day shift and three on the night shift. John Stimberis is the night shift supervisor in winter. Craig Wilbour supervises the day shift. On the west side of Snoqualmie Pass, there is a gun on Dodge Ridge (at the top of the Summit West ski area) to control slopes on the east side of Granite Mtn. A tram is located on the slope above the former eastbound snowshed site. This tram can place charges at several locations along the long starting zone. At "Airplane Turn" on I-5 there is a bicycle-powered tram for placing shots above the road. On the east side of the pass there is a snowshed and a control zone called "Slide Curve" a bit farther east.
Stevens Pass has a smaller WSDOT avalanche crew than Snoqualmie, just two people. White Pass has no permanent avalanche crew. WSDOT people from Snoqualmie Pass occasionally go down to White Pass in winter. While avalanche education has improved considerably in the past 25 years, much of what John does requires on-the-job training with people who have done the work before. Most of the avalanche training available in the U.S. is oriented toward recreation, not highway operations.
Chinook Pass Avalanche Work
Since its completion in the early 1930s, the Chinook Pass highway has been cleared each spring by maintenance crews using heavy equipment. The steep slopes above the road are beyond the reach of the road-bound crews, and snow conditions on those slopes are out of their control. During the first 50 years of this program there were enough close calls during the clearing process and after the highway opened that in the early 1980s the Washington State Department of Transportation (WSDOT) decided to apply avalanche control crews to the problem.
In 1983, Craig Wilbour and others from the WSDOT Snoqualmie Pass avalanche forecasting team began assisting highway maintenance crews on the Chinook Pass opening. Initially, Wilbour and his team hiked from the highway to the avalanche starting zones on foot. They started using downhill ski gear (with Securafix touring adapters) a few years later. As alpine touring gear improved, the avalanche crews adopted it for their work. The Chinook Pass program is unusual in its reliance on ski-assisted avalanche control work to support highway operations. Craig Wilbour presented a paper on the nascent program at the 1986 International Snow Science Workshop (ISSW).
Most of the avalanche control problems at Chinook Pass are east of the pass. There are three main starting zones, called Knob 1, Knob 2, and Knob 3. Knob 1 is a 6240ft peak about 1/2 mile north of Yakima Peak. Knob 2 is a point of similar elevation about 1/2 mile east of Deadwood Lakes. Knob 3 is a bumpy ridge around 6400ft elevation 1/2 mile SE of Sourdough Gap. The 6200ft+ shoulder just south of the ridge is called Picnic Point.
In April, as control work at Snoqualmie Pass tapers off, four people from the Snoqualmie Pass avalanche team move to the Chinook Pass clearing effort. Currently, John Stimberis is the supervisor of this team, assisted by Kevin Marston, Aaron Opp, and Lee Redden. On the day of my visit, John and Aaron were working from the east side of the pass (on Knobs 2 and 3) while Kevin and Lee were working from the west side (on Knob 1). At the 2008 ISSW, John presented a paper updating the Chinook Pass avalanche control program 25 years after its inception.
The Chinook Pass clearing operation is normally conducted on weekdays only, to limit costs. Avalanche control is done using explosives and ski cutting. Ski cutting has been found to be very effective to control surface instability in wet snow, enabling John and his teammates to work large areas quickly. There is a small cable tram on Knob 2, but they haven't used it much. The Chinook Pass team has found that buried explosives are more effective than surface or air blasts to trigger slides in wet snow. The plow crews on the highway normally clear the westbound lane only, leaving the eastbound lane filled with snow until they are ready to open the highway. This helps protect guard rails and stone walls from damage from avalanches running over the road. During my visit, the Knob 1 team triggered an impressive slide that swept powerfully over the highway and descended to the valley bottom.
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