10 August 2020
Rajmala: a deadly landslide in Kerala, India
Posted by Dave Petley
Rajmala: a deadly landslide in Kerala, India
Please see an update on this landslide, now termed the Pettimudi landslide, here.
On Thursday 6 August 2020 a large landslide occurred at Rajmala near to Munnar, Kerala in western India. The landslide, which was triggered by the same spell of intense monsoon rainfall that was a factor in the Air India Express airliner accident on the same day, struck the accommodation of workers from a tea estate. At the time of writing, 43 bodies have been recovered from the site. Reports suggest that a further 28 people are likely to be missing, giving a total toll of 71 people, although there is always considerable uncertainty.
So far I have found little information about the specifics of the landslide, and images that provide a decent oversight are difficult to obtain. The best I have found to date is this one, from India Life and Times:-
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This appears to be a large, flow type slide in highly weathered soil. although better images are needed to understand it properly.
This is the largest landslide in India so far in the 2020 monsoon, although there are several weeks of rain to come yet. Large landslides in Kerala have happened previously. On the same day in 2019 a large landslide occurred at Kavalaparra in Kerala, killing 59 people.
Please see an update on this landslide, now termed the Pettimudi landslide, here.
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Quickslide 1: another deadly landslide in South Korea
On Friday 7 August 2020 another large, mobile landslide struck South Korea. On this occasion the landslide was located in Gokseong County, South Jeolla, killing five people. Korea JooAng Daily has a good image of the landslide:-
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A tropical cyclone is expected to bring more heavy rainfall today.
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Quickslide 2: a seismically-induced rockslide in the Sawtooth Mountains in Idaho
Yahoo has news of a seismically-induced rockslide in the Sawtooth Mountains in Idaho on 7 August. The video is cool, although I recommend sound off (for the sake of those around you and for your own sanity):-
The date given here is seems incorrect. The landslide was earlier believed to have happened in early hours of Friday, Aug 7. However, according to this report published today (https://indianexpress.com/article/explained/how-kerala-munnar-landslide-happened-6549373/) it occurred on Thursday night at 10.45. This also gives more info, including saying the slope was 40 degrees and rainfall figures.
This area is part of Western Ghats and has been experiencing frequent fatal landslides. We have published this Guest Article on landslide mechanisms in Western Ghats by Prof Putty, see: https://sandrp.in/2020/08/08/landslides-in-kodagu-western-ghats-a-critique-of-gsi-report/. Feedback on that is welcome.
Himanshu Thakkar ([email protected]), SANDRP
Good
Very good
The rockslide in the Sawtooth Mountains was worth watching. Shame about the total morons with a very limited vocabulary, doing the ‘commentary’.
Please write about the failure mechanism of Pettimudi Landslip of 2020