On Thin Ice
Is It Safe?
By Farwell Forrest
February 8, 2005
On thin ice. The very words convey a sense of
danger, or at least of dangerous uncertainty. "He's really on thin ice out
there," we whisper whenever someone grabs at a long chance, and then we wait
smugly or apprehensively for the Craack! that we're
certain will follow. Of course this commonplace expression has its basis in
cold fact. The danger is real. Plunging without warning into frigid water,
far from shore and help, isn't exactly a recipe for
longevity, particularly if the water is moving. To be swept under the ice
by a strong current is the stuff of nightmares, after all. But why should this
concern paddlers? Isn't thin ice somebody else's problem? Yes and no. Many
canoeists and kayakers are also skiers, snowshoers,
and winter anglers. If we weren't, we'd be condemned to stay indoors for a
third of the year. Even paddlers who never leave the health-club
gym from Christmas to Easter occasionally run into ice on early-season
river trips. And what about backcountry explorers? Go high enough in the
mountains, or far enough north, and you can meet up with ice well into summer.
I've been stopped cold on big northern
lakes as late as the 4th of July.
The upshot? Unless you paddle only in tropical waters, you'll encounter ice
sooner or later. What then? If you can't hang out in camp till the sun does its
work, and if it isn't practical to walk around the ice that's in your path,
you'll just have to push through it or trudge over it. Either way, it's
a good bet that you'll find yourself walking on ice someday. And when that day
comes, the question uppermost in your mind will probably be
Is It Safe?
Easy to ask, but hard to answer. You can always wait for the first
Craack! and then hope you have time to scramble to safety before you
break through. A lot of people do this every winter, and somewhat
miraculously most of them make it back home. Most of them. But not all.
Smart folks will look for another way.
The best field test of the potential bearing strength of any ice is to cut a
hole through it and check its thickness and quality. One widely-promulgated
rule of thumb suggests that two inches of "clear" ice is safe for an
unaccompanied walker, treading carefully, while as little as three inches will
support a large party walking in single file. The Burlington, Vermont,
office of the (U.S.) National Weather Service is more cautious, however,
warning that "at least" three inches is required to support one person, with
five inches needed for a group. But that's not the whole story. Chopping
through even two inches of ice is hard work, and if you want to be safe, you'll
need to do it often, maybe as often as every few yards. It's a tedious chore as
well as a sweaty one, and for that reason alone, it's a job you're likely to
neglect. An ice auger makes the work much easier, but unless you're an angler
bent on fishing through the ice, an auger's a perishing nuisance to carry. All
in all, digging test holes isn't a practical solution for anyone who's on the
move, let alone a paddler who finds ice blocking his way in summer.
OK. How about using the color of the ice as a guide? Again, the experts
offer helpful hints. New ice is black, and usually both thin and weak. Thick
ice safe ice is gray or bluish gray. Unless it's frozen slush,
that is, whose milky color could easily be mistaken for gray in the half-light
of a typical winter day. Yet slush ice needs twice the thickness of clear ice
to be safe. Nor is this the only difficulty. What if there's a foot of snow on
top of the ice where you're standing? You see the problem. Or rather, you often
won't see it. At best, color is an uncertain guide. At worst, it's a trap for
the unwary. And much of the time it's just plain useless.
Luckily, there's a better way. Take a leaf from the unwritten book of the
circumpolar peoples, men and women for whom crossing ice was a daily business,
as well as a matter of life and death. Get yourself an unaak, short for
unaakpaurak or "little harpoon." That's a pretty good description. An
unaak is an ice-test probe and self-rescue tool in one. And it's simplicity
itself: a long pole with a sharp spike on one end and a big hook on the other.
It's simple to use, too. As you walk, thrust the spike into the ice just in
front of your feet. If it goes through or feels mushy, STOP. If it bounces
back, continue on. Snow is no obstacle, or at least a foot or so isn't. The
spike will cleave it effortlessly. To be safe, test the ice every few steps
before each step if your still, small
voice demands it. Probe. Step. Probe. Step. Probe. In no time at all,
you'll settle into the rhythm. It's almost automatic.
Almost, but not quite. Before entrusting your life to your skill with an
unaak, you'll need to practice somewhere safe, in water you're certain is no
deeper than your thighs, close to shore and free from any current. It's best to
wear a life
jacket and have a friend standing by with a sled, a rope, and a change of
clothing, too. And until you're very sure of your aim, wear shoes with
safety toes. A rubber pac doesn't offer much protection from an unaak's spike.
It's not called the little harpoon for nothing!