A massive November 2020 landslide and glacial lake outburst near Bute Inlet in BC created a seismic signal equivalent to a 4.9 magnitude earthquake! On November 28, 2020, at about 6 a.m., approximately 18.5 million cubic meters of rock dropped from a mountain, slid roughly one kilometer, and impacted the lake at the base of a retreating glacier. The resulting glacial lake outburst created a tsunami 100 meters high and unleashed horrendous devastation for 13 miles downstream in Elliot Creek, forever impacting the landscape there. There is an article about the event in The Tyee, an independent online news magazine in BC. The video below has aerial footage of the aftermath of the event, which wasn’t actually located until later in December because of the remote nature of the site. As always, Dave Petley has a nice discussion of the event on the Landslide Blog. Thanks to the GBA where I first heard of this event.
[Updated Thursday May 29, 2009 – 1:00 PM PDT] Added a photo of the AIS Kaiser S2 excavator (spider excavator), and added photos of the Devil’s Slide debris dump where they have put the landslide material removed and the material from the tunnel excavation. [/Update]
Grant Wilcox, Geology Branch Chief with CALTRANS Office of Geotechnical Design West gave a presentation on the Devil’s Slide repair along PCH Highway 1 at the Southwest Geotechnical Engineer’s Conference on May 12 in Phoenix. I’ve posted about the project here before. When I saw Mr. Wilcox, I knew he looked familiar but I couldn’t figure out why. At the beginning of his presentation he made light of his being on You-Tube…then it clicked! He gave a nice overview of the history of the failures, the geology, and the tunnel project. What follows are a few quick tidbits from his talk based on my notes. (Photo via Caltrans site).
The Mt. Soledad Landslide in a La Jolla California neighborhood destroyed 3 houses and damaged others and it also shut down Mt. Soledad Road for an entire year after it occurred in October of 2007. Residents blamed the city of San Diego, and 65 homeowners filed suit, claiming that leaking pipes caused the landslide and the City should cover damages.
Last week, a superior court judge ruled in favor of the City of San Diego. So far I have not seen anything indicating if the residents plan to appeal the ruling.
One interesting note regarding the trial, the City released an 8-minute cell phone video taken by a geotechnical engineer or drilling contractor employed by the City that showed the road cracking and buckling just prior to failure. The homeowners used the video to try to make their own case. Click through for a portion of the video and a link to the full one.