Snow Avalanches in British Columbia

Every year, avalanches pose a threat to backcountry skiers, snowboarders, snowmobilers, and even highway travelers.

Understanding how avalanches form, recognizing the warning signs, and taking the right precautions can help keep you safe while enjoying BC’s winter landscapes.

What Causes a Snow Avalanche?

Avalanches occur when a layer of snow becomes unstable and slides down a slope. Several factors contribute to avalanche formation, including snowpack conditions, weather patterns, and terrain steepness.

Heavy snowfall, rapid temperature changes, and strong winds can all create dangerous conditions. When weak layers of snow form beneath heavier layers, the snowpack can suddenly collapse and trigger an avalanche.

Types of Avalanches

There are several types of avalanches, each with its characteristics and dangers:

Loose Snow Avalanches – These start at a single point and fan outward as they move downhill. They are usually smaller but can still be dangerous.

Slab Avalanches – These occur when a cohesive layer of snow breaks away from the rest of the snowpack. These are the most dangerous and can travel long distances at high speeds.

Wet Avalanches – These happen when melting snow or rain weakens the snowpack, causing it to slide. They are slower than dry avalanches but can be just as deadly.

Cornice Avalanches – These occur when an overhanging mass of snow breaks off, often triggering additional slides below.

High-Risk Areas in British Columbia

Some of BC’s most popular winter destinations are also among the highest-risk areas for avalanches. The Coast Mountains, the Columbia Mountains, and the Rocky Mountains all experience frequent avalanches due to their steep slopes and heavy snowfall.

Popular backcountry locations such as Whistler, Revelstoke, and the Kootenay region are known for their deep snow and challenging terrain, making avalanche awareness essential for outdoor enthusiasts.

Recognizing Avalanche Warning Signs

(credit: REI)

Before heading into the backcountry, it’s important to look for signs of unstable snow conditions. Recent heavy snowfall or rapid warming can increase avalanche risk.

Other warning signs include cracking or collapsing snow, recent avalanche activity in the area, and hollow-sounding snow underfoot.

If you hear a ‘whumping’ sound while walking on snow, it could indicate a weak layer beneath the surface, which is a serious red flag.

How to Stay Safe in Avalanche Territory

The best way to avoid an avalanche is to plan and make informed decisions. Here are some key safety tips:

Check Avalanche Forecasts – Before heading out, always check the latest avalanche bulletin from Avalanche Canada. These reports provide up-to-date information on snow conditions and danger levels.

Take an Avalanche Safety Course – If you plan to explore the backcountry, consider taking an avalanche safety course. Learning how to assess risk and use safety equipment can be life-saving.

Carry Essential Safety Gear – Always bring an avalanche transceiver, probe, and shovel. These tools can help locate and rescue someone buried in an avalanche.

Link to avalanche safety gear

Travel with a Group – Never go alone into avalanche-prone areas. Traveling with experienced partners increases your chances of survival in an emergency.

What to Do If You’re Caught in an Avalanche

If you find yourself caught in an avalanche, try to escape to the side of the moving snow. If that’s not possible, attempt to stay on top of the snow by swimming or pushing debris away.

As the avalanche slows, create an air pocket in front of your face by cupping your hands before the snow settles. Once buried, stay calm and conserve oxygen.

Rescuers will rely on transceivers and probes to locate you, so always make sure you and your group are properly equipped.

The Role of Avalanche Control in British Columbia

In high-risk areas, avalanche control teams work to reduce the danger by triggering small, controlled avalanches before they become a serious threat.

In ski resorts like Whistler Blackcomb and Revelstoke, ski patrol teams use explosives and other methods to manage avalanche-prone areas.

Highways in mountainous regions, such as the Trans-Canada Highway through Rogers Pass, are also monitored closely, with avalanche control teams using artillery and remote-triggered explosives to keep roads safe.