Citizens for a Livable Cranbrook Society provides grassroots leadership and an inclusive process, with a voice for all community members, to ensure that our community grows and develops in a way that incorporates an environmental ethic, offers a range of housing and transportation choices, encourages a vibrant and cultural life and supports sustainable, meaningful employment and business opportunities.

Friday, July 20, 2012

Slide Tragedies are Likely to Increase in the Future

Perceptions by Gerry Warner
When I first heard the words Johnson’s Landing crackling across the air waves last week, I thought what on earth can this be about. Johnson’s Landing on the beautiful east shore of Kootenay Lake 20 miles north of Kaslo is about as obscure of a place as you can find anywhere in the Kootenays and fewer than 30 brave souls live there.
How on earth did this idyllic hamlet get into the news I wondered with great alarm.
Well, we all know now and our hearts can only go out for the landslide tragedy that took place there.  Four lives have been cruelly snuffed out and it easily could have been more considering the size of the slide which thundered down from the high peaks of the Purcell Range about 80 miles directly northwest of Cranbrook, but much farther if you drive.
So drive is exactly what I did and it took almost four hours to navigate the windy road to Kaslo including the Kootenay Lake ferry and the gravel stretch down to the scene of the slide. But the best look I got of it was with my binoculars from the opposite side of the lake directly across from Johnson’s Landing.

It was a pretty impressive look.
































The slide must have started from near the 8,000 ft. level of Kootenay Joe Mountain, which is just outside the Purcell Wilderness Conservancy and still covered with the odd snow patch. It looked like it originated in several steep ravines at that level with the various smaller volumes of dirt, debris and mud combining lower down to form one giant stream of rock, rubble, splintered trees and mud which roared all the way down to the lake shore sweeping away everything in its path.
Given the steepness of the slopes, the slide must have moved really fast giving the victims below no real chance or warning to get out of its destructive path. One Johnson’s Landing resident, who was incredibly lucky to live just beyond the edge of the destruction, got a warning only hours before when she noticed the normally crystal waters of Gar Creek silting up and a lot of wooden debris floating down the swollen creek. She fired off an email to the Ministry of Forests but no one saw it until after side of the mountain broke away.
Now, of course, comes the “why game” and the “blame game,” but frankly I don’t think there is much to say about the latter. As I drove over to Kootenay Lake, one of the things I was wondering about was clear-cut logging, which has been rightfully blamed for many Kootenay slides over the years. But after carefully scoping all the slopes around and above the torrent of rock I could see no evidence of logging whatsoever. In fact, most of Gar Creek’s drainage appeared to be covered by mature timber so logging of any kind can definitely be ruled out.
What then? A geological fault? Quite possibly. A small earthquake. Also possible, but no evidence of that yet but it shouldn’t be ruled out because the 1960’s slide that many of you will have driven through on the Hope-Princeton Highway was eventually blamed on a small earthquake in Washington state just to the south.
And then there’s the standard bugbear of global warming. Many will roll their eyes at this point, but you shouldn’t be too quick.  
An article in the Vancouver Sun this week said the slide should be a “wake up call” that climate change is increasing the risk of slide incidents such as the Johnson’s Landing slide and the one at Fairmont and a series of small slides following a big rain storm in Castlegar Tuesday.
Unstable slopes are a fact of life in all mountainous areas and when you combine that with increasingly erratic weather associated with climate change you’ve got the potential for tragedy. The heavy snowpack this year, combined with a late spring and one of the wettest Junes on record with Cranbrook airport recording 123 mm of rain (about five inches) the local mountains have got awfully soggy and that has got to be a concern.
Could a slide tragedy happen around Cranbrook? No one can say for sure. But City Public Works Director Joe McGowan says there are electronic silt and turbidity detectors at the intake just above the Phillips Reservoir that should give an early warning if a slide event happened in the upper reaches of Joseph Creek.
This is cause for comfort, but one can never be too sure.

Gerry Warner is a retired Cranbrook journalist and a Cranbrook City councillor. His views are his own and he is not speaking for Cranbrook Council.

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