22 November 2021
The British Columbia landslides and floods – new images of the impacts
Posted by Dave Petley
The British Columbia landslides and floods – new images of the impacts
Over the last few days new sets of images have been posted online of the enormous impact of the landslides that affected parts of British Columbia a week ago, caused by an exceptional rainfall event. The most comprehensive images that I have seen were posted to Twitter by Brent Ward (@GeoBrentatlarge) from Simon Fraser University, resulting from a helicopter flight that he took with my former PhD student Sergio Sepulveda, also of SFU. The Twitter thread is is below:
https://twitter.com/GeoBrentatlarge/status/1462474502055481344
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Meanwhile, Jeremy Venditti (@VendittiLab), also from SFU, has posted some images of the terrible impacts at Tank Hill on Highway 1:-
Many have seen the mess at #TankHill that closed #Highway1. Few have seen the source area. No point source, just too much water on hydrophobic soils, burnt by the Lytton fires. A flood turned to a landslide. A classic natural hazard cascade. #BCStorm #BCLandslides #BCfloods pic.twitter.com/5evy7841xT
— Jeremy Venditti (@VendittiLab) November 21, 2021
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Meanwhile, BC Transportation has compiled a gallery of images including over 100 photographs and seven videos of the impacts of the extreme rainfall. This for example is an image from Tank Hill:
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The human cost of the disaster has slowly increased as the recovery operation has continued. At least four people are now known to have died in the landslides, with one more person missing. The three new confirmed fatalities occurred in the Duffy Lake area.
The Mining Journal has an interesting article focusing on the impact of the events on the extractive industries in the area, most notably the rail links that are the primary route for moving the ore to the coast. There is also damage to pipelines used to transport crude oil and other hydrocarbon products, leaving fuel shortages in some areas. Another potential impact that is causing concern is the fisheries industry, with concerns that the large volumes of water and sediment may have damaged wild salmon spawning grounds.
Unfortunately further heavy rainfall is forecast in the area. This is not expected to be an extreme event, but with the ground already saturated the impacts might be greater than would be expected normally.
In regard to future foul weather expected in BC, I note a large Brumadinho-style tailings dam and associated 9 km long pond about 40 km NE of Tank Hill on a tributary of the Thompson River.