This year's unusually low snow fall has us all a bit stirred up. As a team accredited by the Mountain Rescue Association (MRA), each year we are required to go through a re-accreditation process in one of three mountain rescue disciplines; Technical Rock, Technical Snow & Ice, and Wilderness Search. This year, we were slated to join other MRA teams from the region in early March for the technical snow and ice re- accreditation. Sadly, last week the decision was made to postpone the event until next year due to inadequate snow cover.
As San Franciscans have basked in the sun and enjoyed a beautiful "June-uary" here by the bay, BAMRUvians have been cancelling or rescheduling snow trainings, and scrambling to find areas where we can practice these important rescue skills.
The last weekend of January, 12 team members headed up to Tahoe and camped out near Donner Summit. There was just enough snow to demonstrate an avalanche pit and build a few impressive snow shelters. We were able to place snow pickets, build a few bollards, practice beacon searches and a probe line. While we were able to accomplish all of our goals, the snow level was less than impressive. Soon after this lack luster introduction to winter, what little snow there was has continued to melt even more.
Two of our dedicated team members weren't going to let this dry season get in the way ofrefreshing their crevasse rescue skills. Eszter and Chris made the best of the blue skies and headed out to the beach this past weekend to brush up on their Z-rigs and snow anchors.
The results are below:
"It proved impossible to pound a snow picket in vertically more than 6" - at least, not without using a heavier hammer than we had brought. That happens in hard-pack snow sometimes, at which point you either dig a T-slot (bury the picket horizontally) or declare it ice and use a screw.
Digging a shallow T-slot in wet sand proved completely reasonable, which was
really surprising. It's a lot like digging one in snow - there's enough
cohesion in the sand that the slot maintains enough integrity that you can form
all the component parts and bury the picket and have something that looks like
an anchor.
But it isn't really an anchor. The big difference shows up here: if you stomp on snow, either before digging to "work harden" it, or after burying to compact it, you are forming new, larger, crystal structures that contribute to the integrity of the anchor.
This doesn't happen in sand. So all you have for anchor integrity in the sand is, basically, the weight of the sand plus a *little* "mud effect", where there is some localized cohesion of the particles, basically through the surface tension of water (I'm guessing).
So light tension on the line to simulate a load while building and operating
the system was completely reasonable. But once we started to try to haul even a bodyweight load, the anchor ripped right out."
Hopefully the snow will eventually come, and we will be able to put our beach skills to use. In the meantime, three thumbs up for creative and fun training solutions. Our puffies, shovels, ice axes and pickets are waiting!
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