‘Waiting to go’: Scientist says third slide on Joffre Peak imminent
Posted May 22, 2019 8:06 am.
Last Updated May 22, 2019 8:18 am.
This article is more than 5 years old.
BURNABY (NEWS 1130) – The North Face of Joffre Peak remains unstable and a third slide could occur at any moment, according to a professional geologist who has been analyzing footage and photos of the mountain.
An estimated five-million cubic metres came off the peak in the May 13 and 16 slides — one-million cubic metres in the first, and four-million cubic metres in the second.
Drew Brayshaw works with Statlu Environmental Consulting Ltd. but his analysis of Joffre is a personal side project.
“When I was looking yesterday I could see that there was a fresh crack to the left of what had failed previously,” he says.
Given the back-to-back nature of the first two slides, the record high temperatures that preceded the events and photographic evidence of a growing crack, he says a third slide is likely imminent.
“Based on the timing of the first two I would expect it will be sooner rather than later. Whether that will be today, whether that will be in a week or a month or a year, I don’t really know,” says Brayshaw.
Millions of tonnes of debris
Brayshaw is guessing about 5 million cubic metres of rock and ice slid down Joffre Peak last week.
He’s basing his estimates and predictions on aerial footage and photographs gathered by hiker Wilfried Braun and pilot Daniel Jun on Saturday, May 18.
While last week’s slides caught a lot of attention, Brayshaw says it turns out there were a number of smaller rock falls from where the slides occurred over the preceding weeks.
“That’s always a sign of instability,” he says.
Brayshaw spotted the crack when he was going through their footage and says it’s an indicator that a third buttress could come down.
“It’s like books falling off a bookshelf you know, they slide a little bit and then one goes and everything else is hanging and now a second piece is gone and there’s a third waiting to go,” he says.
The debris and slide path nearly ran to the highway. It stretches about 4 kilometres down Cerise Creek, blocking the Cerise Creek access trail.
The river of ice, rock and snow stopped before reaching the Highway 99/Duffey Lake Road and no one was in the parking lot at the time.
