On Thursday, Jan. 24, Eaglecrest Ski Area opened with two feet of new snow. Folks were eager for powder skiing, but ski patrol seemed to take its time to open terrain, leaving both east and west bowls closed until the next day. It seemed like it took forever. The fact of the matter is, it didn’t. Avalanche forecasting for a ski area is not an easy matter. A painful reminder of that happened in Colorado last weekend when two inbound avalanche fatalities occurred in two different ski areas within the same day. The first accident happened in Vail when three skiers skied into a closed area. One of the skiers, a 13-year-old, triggered an avalanche, got partially buried and killed. The other avalanche was in Winter Park, where a skier got buried in an avalanche and killed in an open area.
When new snow falls, avalanche forecasters try to evaluate the distribution of the newly fallen snow across the mountain, the effect of the new snow on all existing snowpack layers and what it would take too start an avalanche. Forecasters need to make sure that areas with potential for avalanching and adjacent areas are closed. The responsibility is enormous; a mistake can cost lives.
Avalanche control programs, other than ski areas, are mainly concerned with natural avalanches. It is reasonable to assume a snowpack that is not sensitive to artificial triggers is also unlikely to produce natural avalanche without drastic changes in loading patterns or temperatures. Ski patrollers, like other avalanche control programs, use explosives and ski cuts to test the slope. However, a ski patroller’s concern lies primarily with human triggered avalanches, rather than natural ones. Hence, they cannot assume that if they didn’t trigger an avalanche, the next skier wouldn’t either. Guides and other backcountry travelers can improve their odds by avoiding avalanche-prone areas or terrain traps like gullies or cliffs. Ski patrollers don’t have that luxury; everyone that has skied in a ski area knows that by the end of the day everything gets tracked up.
To better understand the complexity of ski area avalanche control work, imagine this scenario: you decided to throw a super bowl party. The party gets out of hand and becomes rather wild. Early the next day, your mom calls and tells you that she is on her way, and she is planning to stay for a week. You rush to clean the house where the most embarrassing evidences of wrong doing are likely to be. As she pulls into the driveway, you sweep the living room and find nothing incriminating. You know that she will find any evidence that you may have overlooked. How confident are you that your mother’s visit will go smoothly?
The same goes for ski area avalanche control, tossing a bomb on a slope does not guaranty an avalanche will be triggered, nor is it a sure indicator for stability. There may be other spots on the slope that are easier to trigger an avalanche from. If ski patrollers miss one of those spots, someone will find it and trigger an avalanche.
Still with all the challenges of making a ski area safe, ski patrollers are doing a great job and the snowpack inside the ski area is far safer than on the other side of the boundary line. Heavy skiing and avalanche control work stir the layers in the snowpack and limit their continuity. As result, they also reduce the odds that an avalanche will develop. The snowpack outside the ski area is relatively untouched. This distinction is sometimes easy to miss, especially in an open boundary ski area like Eaglecrest. Several times, as I was hiking the ridge, I have seen teenagers leave the ski area boundary and venture into the sidecountry. Occasionally, I turn my avalanche beacon to “receive” to see if any of them carry avalanche safety gear. It is rare that I receive any signal from a transmitting beacon. Being a parent myself, I sometimes wonder if their parents are aware of their kids playing in the potentially dangerous snowpack of the sidecountry, or they assume that their kids play in the safer environment of the ski area’s boundary.
• Ron Simenhois is an avalanche forecaster who lives in North Douglas. You can contact him at firstname.lastname@example.org.