Where do landslides occur?


Where do landslides occur?

Some areas of British Columbia are more susceptible to landslides than others because
of their unique geological conditions:

The sedimentary rocks of the Skeena Mountains are the most prone to large slumps and shallow slides in the province.

Debris flows and torrents often occur in the humid west coast of Vancouver Island and the Queen Charlotte Islands within the Insular Mountains.

Dormant volcanic centres in the Coast Mountains (e.g., Mt. Garibaldi) are susceptible to rock and debris avalanches and flows.

Thick clay and silt-rich glacial sediments in the Northeastern Plateau are prone to soil creep and are frequently undercut by rivers, which results in slumps.

The steeply dipping beds of sedimentary rocks in the Rocky Mountains are prone to rock slides, topples, falls and avalanches.

The Interior Plateau contains weathered volcanic rock and glaciolacustrine sediments that are particularly susceptible to creep, slumping and sliding.

Metamorphic rocks in the Columbia Mountains are prone to rock slides and slumps.

Population centres and transportation routes in British Columbia are exposed to a great variety
of landslides.

This structure near Williams Lake received considerable damage in 1992 from undercutting of the slope (photo courtesy of the Ministry of Health).

The Spences Bridge Slide dammed the Thompson River in 1905 and is typical of other slides in the Interior Plateau (photo courtesy of the Ministry of Environment, Lands and Parks).

**Historical Landslides in British Columbia**
Date	Name/Location	Type	Comments
1855-56	Rubble Creek/Garibaldi (The Barrier)	Rock avalanches	30 million cubic metres of rock dislodged
1880	Haney Slide	Clay slide	Displacement wave 12 metres high created by the slide caused 1 death
1888	Ashcroft	Silt slide	15 million cubic metre slide blocked Thompson River for 2 days
1898	Big Slide/Quesnel	Sediment slump-flow	Damaged homes, farms and a highway
1905	Spences Bridge/Thompson River	Silt slump	Resulting wave caused 18 deaths
1914	Hell's Gate/Thompson River	Rock fall	Millions of dollars in lost fish stocks and in repair of fish migration corridor
1915	Jane Camp/Britannia Mine	Rock avalanche	200 000 cubic metres of rock; 56 deaths
1921	Britannia Creek/Howe Sound	Debris torrent	37 deaths
1931	Meager Creek/Pemberton	Debris flow	Glacial dam burst, over 5 million cubic metres of water and debris
1957	Prince Rupert	Debris flow	Debris 17 metres thick; 7 deaths
1965	Hope Slide	Rock slide	British Columbia's largest rock slide; 4 deaths
1968	Camp Creek/Revelstoke	Debris torrent	76 000 cubic metres of debris; 4 deaths
1970	Summerland	Silt fall	1 death
1971	Boston Bar/Fraser River	Slump	Train derailed in slump; 3 deaths
1972	Sparwood	Debris flow	Mine waste movement; 2 deaths
1973	Attachie Slide/Fort St. John	Clay slump	Over 24 million cubic metres of sediment
1973 & 1975	Port Alice	Debris torrent	2 events, 22 000 cubic metres
1975	Devastation Glacier	Rock avalanche	13 million cubic metres; 4 deaths
1981	M Creek/Howe Sound	Debris torrent	20 000 cubic metres of debris; 10 deaths
1983	Alberta Creek/Howe Sound	Debris torrent	15 000 cubic metres of debris; 2 deaths
1990	Philpott Road/Kelowna	Debris flow	Heavy rain; 3 deaths
Ongoing	Wahleach/Lower Fraser Valley	Creep	60 million cubic metres, $25 million on engineering controls
Ongoing	Downie/Revelstoke	Rock slide, slump	Millions spent to control more than 2 billion cubic metres of rock

The Attachie slide of May 26, 1973 west of Fort St. John dammed the Peace River for approximately 10 hours (photo courtesy of Thurber Engineering Ltd.)

In 1898, the Big Slide of Quesnel destroyed homes, farms and part of a highway (photo courtesy of the Ministry of Transportation and Highways).

Next Page - How do landslides affect us?
Landslides Home
Previous Page - What are the different types of landslides?

Landslides in British Columbia was originally produced as Information Circular 1993-7 by the BC Geological Survey of the B.C. Ministry of Energy, Mines and Petroleum Resources in cooperation with the B.C. Ministry of Health, the B.C. Ministry of Transportation and Highways, the B.C. Ministry of Environment, Lands and Parks, the B.C. Ministry of Forests, the B.C. Provincial Emergency Program, and with the assistance of the Geological Survey of Canada.

Copies are available from:

Publications Office
BC Geological Survey
Ministry of Energy, Mines and Petroleum Resources
P.O. Box 9333. Stn Prov Gov't
Victoria, B.C.
V8W 9N3

This page was updated: March 08, 2006.