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Avalanche Safety at the Colorado Huts
Even the Small Ones Can Kill You
By Louis Dawson
After more than one close call with snow avalanches, I'm blessed
to be alive. If anything, my peccadilloes
have taught me one thing: In Colorado, winter backcountry skiing
can be a battle of wits bordering on jihad fanaticism. An example:
Sitting in the Betty Bear hut on Colorado's 10th Mountain Trail,
we look south at an inviting ski slope. It's a little thing, perhaps
300 feet of vertical, steep enough to avalanche, but not an obvious
slide path: no obvious demarcation such as the classic swaths
you see cut into mountain sides worldwide.
There are a few signs, however. First is the shape and exposure
of the slope, a leeward convex bulge, devoid of trees, wind-loaded
with a pregnant belly of snow. The conifers at the base of the
slope are not obvious avalanche trees with heavily stripped branches
and scarred bark, but to the trained eye they tell a story of
abuse. What I see is enough -- with years of experience (including
plentiful mistakes) my avalanche eyes are tuned, and the slope
looks like something to avoid.
Nonetheless, I need to reach the top of the pitch to take photos
of the hut. So we climb a conservative line to the left, on lower
angled ground with denser trees. About half way up we realize
the snow is in bad shape, breakable crust and worse, so my companion
Andrew Meeker leaves his stashed below the last pitch of windpack
and boots the rest of the way.
Just after we top out, the proverbial WHUMP echos through the
forest as the snowpack does a massive settlement, birthing a hard
slab avalanche just twenty feet below us. We watch in stunned silence
as the slab liquefies, then piles up in a deep plug at the bottom
of the slope -- a killer for sure if we'd been in it.
How was our route finding? Our up-track was still intact except
for one small section. Where Andrew had dropped his planks, the
slide had washed over our line by just a few feet and carried
his skis away (Andrew was not a happy camper...).
Our score? If the slide had triggered while Andrew was messing
with his skis, he might have been swept away -- but then again,
if he'd had the presence of mind to take two steps to the left
when the slide triggered, he would have been totally safe. I couldn't
help but note that my own tracks were 100% safe. Experience or
luck? I'm not sure. I'd give us a "C" for route finding
and a "B" for judgment.
Most importantly, note that it was the difference of mere feet
that made for one totally safe route, and another that risked
death. This validates what I call "micro route finding,"
an avalanche safety skill I believe is significantly more important
than snow science, and much harder to learn. It's the art of using
subtle terrain variations to avoid small, but nonetheless deadly
slides. You can not gain this skill from books or classes. You
learn it by being outside, observing the world around you through
a lens of fear and conservatism, perhaps while following a mentor
who has the knack. And all the while, you've got to remember how
easily human error enters in -- that's the lesson I learned from
this skirmish in the avalanche jihad.
(The Forest Service avalanche advisory for the day of our
adventure was "low/moderate," but a sudden warming trend
pegged the danger way past that. One of Andrew's skis was lost
till he retrieved it that summer. We didn't need a trip to the
underwear store, but Andrew's eyes stayed wide for a few days,
and I returned home humbled, resolving to do better. If
anything, this is a good example of how Colorado can build good
mountaineers -- it's not a forgiving environment -- mistakes are
costly -- if you survive you learn...)
A few tips for micro route-finding and behavior
on a tender snowpack
- First, know that most 10th Mountain designated route had little or no avalanche danger. BUT, routes accessed from the huts may have everything from small slide paths to gigantic avalanche chutes of world-classs porportions. Thus, if you choose to travel in such terrain, heed the following:
- Look for a route that chains lower angled terrain with islands
of safety, so you never set foot on steeper terrain.
- Load a slope with as few people as possible. Keep your party
spread out, and travel in small groups.
- Use vegetation to read the slope, but don't depend on sparse
trees to anchor a tender slab. If conditions are touchy, only
trees tight enough to make you cuss will anchor the snow.
- Avoid wind loaded "pillows" and convex starting
zones.
- If you're route exposes you to danger, pick a line that minimizes
the consequences of an avalanche (e.g., getting swept into a
gully is worse than tumbling into a fanned out debris pile).
- Consider subtle variations of slope aspect. In Colorado, just
a slight tilt to the west or east, rather than dead northerly,
can make a route much safer.
- Learn the subtleties of wind loading (in other words, throw
away the books, forget expensive and time consuming advanced
certifications, just go to the backcountry and look/listen/feel.)
- If traveling in a valley during a time of high avalanche danger,
remember that large slides can pound the valley floor. These
events are usually unsurvivable. Use your imagination as you
pick a route, and choose a line that avoids your horror fantasy.
- It bears repeating: Use ridges to reach summits. If the signs
of avalanche danger are in the red zone, ski back down your
ridge route (use all that skill and expensive gear you've acquired
to make tight and precise turns on a narrow ridgeline track).
- Avoid falling and wallowing on avalanche slopes. If you can't
ski without falling, improve your gear or technique, or dial
back your expectations.
- On the way up, avoid post-holing and trenching. Use over-snow
equipment such as skis, a split snowboard, or large snowshoes
that don't punch a deep track. While snowshoes may work well
on a track previously broken by a skier, most smaller 'shoes
will cause you to wallow in virgin winter snow. If you're serious
about winter backcountry snowboarding in Colorado, get a splitboard.
- As I mentioned in the article above, travel with a mentor,
stay behind them, and think about the moves and choices they
make.
- Every backcountry winter traveler should have some level of avalanche safety education. More, consider hiring a guide if you're inexperienced and still choose to travel in avalanche terrain. Please see our FAQ for guide service suggestions.
- Above all, in a bad Colorado snowpack, be cautious and conservative
to the point of absurdity.
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