Landslides in Canada

Landslide blocked Highway 16 between Hazelton and Terrace, BC, May 28, 2007. Photo credit: Greg Ross, BC Ministry of Transportation

For more info on landslides

• Atlas of Canada
• Canada Landslide Loss Reduction Initiative

Thousands of landslides occur every year in Canada, but most are small. They occur in all regions but are most damaging in the mountainous regions of British Columbia and Alberta and in the St. Lawrence Lowlands of Quebec and Ontario. Large landslides are less common, occurring only about once every 10 years in Canada.

• Landslide facts
• Minimizing the risks from landslides
• How to protect your home against landslides
• What to do during a landslide
• Include this page in your emergency plan

Landslide facts

• A landslide is the downward movement of rock and/or loose sediment, triggered by natural processes or human actions. 
• The speed of a landslide can range from extremely slow to extremely rapid.
• The largest Canadian landslide known occurred in 1894 at Saint-Alban, Quebec. It involved 185 million m3 of material and created a 40 m deep scar that covered an area of 4.62 million m2 (roughly the size of 80 city blocks).

Minimizing the risks from landslides

Landslide risk can be minimized by various methods, including:

Avoidance

• With expert input and careful planning, communities can identify unstable slopes and restrict or control development in hazard zones.

Protective measures

• For communities that are already established, the municipal or provincial authorities must consider whether protective engineering measures or buy-outs and moving of people and buildings should be undertaken.

Engineered solutions

• If unstable slopes cannot be avoided, there are numerous engineered solutions to deter landslides including:
  • improving drainage
  • reducing the angle of the slope
  • excavating to unload the top of the slope
  • building a protective berm or wall to buttress the bottom of the slope

Containment or diversion structures

• Where landslides can neither be prevented nor avoided, a number of physical containment or diversion structures have been designed, including:
  • catchment dams and containment basins to control debris and water
  • artificial channels or chutes to redirect debris flow
  • nets and artificial walls to prevent falling rock or earth from hitting roads or structures

How to protect your home against landslides

Atlas of Canada landslide map

Although landslides usually occur without warning, understanding this natural hazard and following some sensible rules can help to protect your family and home.

• Learn about your local geology and the potential for landslides in your area.
• Avoid actions that would increase instability. For example, do not undercut a steep bank; do not build near the top or base of steep slopes; do not place fill on steep slopes; do not drain pools or otherwise increase water flow down steep slopes.
• Learn how to recognize signs of potential failure in your locality. Examples include slope cracks, slope bulges, unusual seepage of water on the slope, and small rock or sediment falls.
• Know who to notify if you recognize these signs (e.g. municipal emergency contact numbers and municipal engineers).

What to do in case of a landslide

If indoors

• Find cover in the section of the building that is furthest away from the approaching landslide.
• Take shelter under a strong table or bench.
• Hold on firmly and stay put until all movement has ceased.

If outdoors

• Move quickly away from its likely path, keeping clear of embankments, trees, power lines and poles.
• Stay away from the landslide. The slope may experience additional failures for hours to days afterwards.

Include this page in your emergency plan

If you live in an area that is on or near a slope or in a region susceptible to landslides, print this information and include copies in your emergency plan and emergency kit.