I do a fair amount of skiing in the backcountry, often solo, and I’ve thought a lot about what I would do if something went wrong and I had to bivouac overnight. What would I do for shelter?

Snow shelters commonly covered in outdoors books include the igloo, quinzee hut, and snow cave. But all of these take considerable time and effort to build. I figure if I can build an igloo, I probably can get out of the woods—in which case I don’t need an igloo.

Moreover, the snow conditions in the Adirondacks are not ideal for building igloos and snow caves. For igloos, you want wind-packed snow that can be cut into blocks. For snow caves, you want drifts that are at least six feet deep. You might be able to find appropriate snow in some places in the Adirondacks, but the chances are slim that one of them will be the place where you break an ankle.

A quinzee hut, in contrast, can be built just about anywhere there’s snow. Basically, you shovel snow into a large mound, wait a few hours for the snow to set, and then dig a room inside the mound. In an emergency, though, you want something that’s quicker and easier to construct.

Like a snow trench.

“In the Adirondacks, if you’re in an emergency situation, most of the time a trench is the most practical shelter,” says Jack Drury, an outdoors author who founded the Wilderness Recreation Leadership Program at North Country Community College in Saranac Lake.

For a trench, you’d like the snow to be at least three feet deep. If it’s not, however, you can use excavated snow to build up the walls.

A one-person trench should be dug three or four feet wide and six or seven feet long. Drury recommends leaving at least five or six inches of snow at the bottom as insulation against the cold ground.

Given enough time, you can create an A-frame roof from slabs of snow, but in an emergency, you can just lay branches and evergreen boughs across the trench and then place snow over the boughs for insulation. If you have a tarp or a waterproof shell, lay it over the boughs before piling on snow. Once inside, stop up the entrance with your pack to keep warm air from escaping.

Drury recommends that winter travelers keep a piece of closed-cell foam in their packs to use as a sleeping pad. It should be long enough to stretch from your shoulders to your butt. If it’s an emergency and you don’t have a pad, place evergreen boughs on the bottom of the trench for insulation. He also recommends carrying a lightweight sleeping bag or heavily insulated pants and jacket for emergencies.

“You might not be comfortable, but you’ll survive the night,” he said.

Drury said the temperature in a properly constructed snow trench should stay in the twenties even if it’s colder outside.

Drury is the author of The Backcountry Classroom and Camper’s Guide to Outdoor Pursuits.

You can read more about building snow shelters in Mountaineering: The Freedom of the Hills, published by The Mountaineers Books, and How to Build an Igloo And Other Snow Shelters, by Norbert E. Yankielun.

Photo: A quinzee hut, courtesy Wikipedia.