Avalanches: Being Prepared for Backcountry Adventure

You're skiing midway down a steep, snow-covered mountain slope. A metre of new snow fell just hours before. Winds are light, but are causing some snow to drift. The sun peaks out from behind an otherwise overcast sky. Snow begins to shift from high above, then gains momentum. A wall of snow suddenly roars down the mountain slope at 120 kilometres per hour. An incredible spectacle though terrifying to anyone caught in its path. Avalanches are too fast to outrun.

An avalanche is a mass of snow falling suddenly down a mountain slope, often picking up earth, rocks and debris in its path. There are two types of avalanches: slab (cohesive snow) and loose (non-cohesive snow) and for each the snow can be wet, moist or dry. Most avalanches are dry slab, usually occurring on slopes of 25 to 40 degrees – and because both skiers and snowmobilers like to ride on these slopes this is where a person is most likely to trigger an avalanche. Most fatal avalanches are triggered either by the person caught, or another member of their group.

Avalanche accidents kill an average of 16 people in Canada every year, making snow avalanches the single greatest threat to winter recreation in the mountains. However, 86 per cent of those caught in an avalanche do survive. If you are caught in an avalanche luck, survival skills, and having companions with the tools and training to immediately rescue you are critical. However, it's best to avoid being caught in the first place.

Backcountry recreationalists need to keep informed of weather conditions and avalanche danger. Planning has to be precise: know what route will be taken and the level of risk on each part of the route. Deciding on your destination for the day should only be made after doing this research, and you should be prepared to turn back if conditions are more dangerous than expected.

Be Aware and Be Prepared

Indicators of avalanche probability include slope angle, slab thickness and density, type of terrain including number of trees, level of sun exposure, snowfall, temperature, humidity, wind-speed and direction. New snowfall, especially when accompanied by wind and rapid temperature change are two important causes of avalanches.

The Canadian Avalanche Association creates bulletins which forecast the avalanche danger for various mountainous locations in western Canada and Quebec. These bulletins provide information on the weather, snowpack, recent avalanches, and offers travel advice along with an overall rating of avalanche danger.

Those going on a backcountry winter adventure should contact Environment Canada (1-900-565-5555) whose meteorologists have immediate access to more detailed current weather information. When talking with a meteorologist, be prepared to give as much information as possible about where you are going, when, and the elevation. Ask for recent temperatures, winds and snowfall at the closest weather station. Call ahead of time to give the meteorologist time to research your questions (it will cost less to make two calls, than waiting on hold while the research is being done). Then check back with the meteorologist (preferably someone who has your profile) for any last-minute weather changes before leaving.

Being safe means being prepared. Map out the trip in detail. Travel with others and practice rescue techniques. Carry radios and ensure they are in good working order. Take an avalanche course - it can be fun and interesting. Review avalanche bulletins and phone ahead of time for avalanche and weather information. Be prepared to change plans based on the weather and avalanche reports. Assure that everyone on the team is equipped with the right tools, maps, experience and physical fitness level needed for the trip. And, leave a copy of the route with someone who is not travelling.

Mountain adventure is breathtaking. And, Canada has many national and provincial parks to enjoy backcountry winter adventures. Travellers just have to make sure they have the knowledge and skills required to have a safe and fun adventure.