Backcountry basics: Digging into avalanche rescues
Day two of the Colorado Mountain School Level 1 Avalanche Course was when the real action got underway.
After waking early and grabbing a quick breakfast our entire class met for a pre-trek briefing at CMS’s classroom in Estes Park. The combined group of 22, including 18 students and four instructors, reviewed the day’s avalanche forecast from the Colorado Avalanche Information Center. We recorded data regarding specific terrain and avalanche dangers along with snowfall and weather details into our AIARE Field Books, often referred to as “Blue Books” by the CMS guides.
We headed up into the high country west of Estes Park, specifically to the former ski resort that was located in Rocky Mountain National Park known as Hidden Valley. The slopes of the resort, which closed in 1991, are still popular with backcountry riders and old ski runs provided easily followed trails for our ascent to a snow covered segment of Trail Ridge Road, where we conducted most of our formal course work for the day.
Trail Ridge Road rolls past Hidden Valley in two places as the road climbs up to the alpine territories that lead over the Continental Divide to Grand Lake. The road is still open at the entrance to Hidden Valley but Parks Service employees close the road for the winter not far from the former ski resort at Many Parks Curve. The second segment of the road that bypasses Hidden Valley is located high above the area’s parking lot and not far from treeline.
After arriving at the Hidden Valley parking lot my group and I, guided by our instructor, Ben Markhart, headed up the gut of the old Columbine blue run, snowshoeing on the hard packed snow and icy slopes. As we moved up towards Trail Ridge, Markhart gave our group impromptu instructions on terrain selection, potential terrain traps, and slope angles all with the explanation that such considerations should always be at the forefront of our minds when moving through the backcountry.
A little less than two hours after starting up the trail we found the road and started more formal instructions. Our guides had us conduct a quick field test of our avalanche beacons. We had previously tested the beacons to ensure they were working but our instructors wanted us to get a better sense of the differences in range for the various types and models of beacons.
After checking beacon ranges our guides headed off to bury extra beacons under the snow and the four groups in our class each headed off to learn the basics of avalanche rescue. We delved into the way avalanche beacon signals arc out from their source, which often confuses rescuers. We practiced proper probing techniques and the spirial pattern searchers should employ after locating an avalanche beacon signal. We tried our hand at digging as our instructor highlighted the importance of digging forwards and upwards to a buried subject, and not digging directly down.
We were also hit with a few jarring facts. According to our guides, a person has an average of about 15 minutes of being buried by an avalanche, giving rescuers roughly 15 minutes to find a person and get that person out. Our instructor stressed the absolute importance of finding a subject with beacons and probes before the digging process occurs.
“There is no second digging in avalanche rescue,” Markhart said. “If you have to dig a second time that person is dead.”
After running each member of the team through several iterations of a rescue scenario we moved on to digging snow pits and the conducting of snow stability tests. We reviewed snow density and strength, examined the multiple layers deposited on the mountainside and tried to wrap our minds around the unique dynamic that exists between air temperature, snow depth, and the faceting or rounding of snowflakes that occurs over time.
As the sun started heading for the western end of Rocky we headed back down Columbine trail to the Hidden Valley parking lot, with our guide quizzing us as we went.
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