13 April 2017

Shimla and Idaho: two new, and very different, landslide videos

Posted by Dave Petley

Shimla landslide video

An excellent video has been posted on Youtube of a landslide that occurred at Shimla in Himachal Pradesh in India on 7th April.  The landslide has occurred on a slope that appears to have been cut as part of a construction project that is in the foreground:

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The apparent lack of slope support at this site seems bizarre given the materials from which this slope is formed:

Shimla

Landslide on a cut slope at Shimla in India, via Youtube

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I have to admire the coolness of the construction workers, who seem remarkably unconcerned about this developing slope failure.  Amazingly, the main failure event was captured from a second angle as well:

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It appears the the highway is the road that links Shimla and Chandigarh.  The construction site may be the base station for a ropeway and a shopping mall.

A gentle landslide from Idaho

Meanwhile, the Weather Channel has posted a most elegant video of a smaller landslide that occurred above a road in Idaho:

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I have rarely seen such a gentle, almost balletic, landslide.  Amazingly, it did not even cause the light pole at the toe of the landslide to topple as it was gently moved across the road.  The Idaho State Journal has an account of this landslide:

ITD crews were on scene with cameras rolling as a hillside broke free and covered a section of U.S. 95 south of Bonners Ferry on Friday, April 7.  In the video, you can see tons of mud, rocks, and trees slide down, pushing two layers of concrete barriers off the road. Overall, 800 cubic yards of debris slid onto the road.  Thanks to quick action of ITD crews on scene, no one was injured by the slide. ITD Land Surveyor Mathew Wilson, who took the video, was assessing the hillside stability. He heard popping and cracking and knew another slide was imminent. Thinking quickly, the flaggers on scene stopped traffic and just three minutes later the hillside gave way. ITD crews cleared the debris from the road Friday evening. Additionally, crews dug out an extra 600 cubic yards of dirt beside the road to create a channel for water to run.