3 October 2015
El Cambray Dos landslide
(I wrote this a few days ago but for some reason failed to publish it. I upload it here for information)
A very large landslide struck the small village of El Cambray Dos, near to Guatemala City, earlier this week, with catastrophic effects. Whilst there are wild variations in the loss estimates at present, the known death toll is at least 26 people, with an unknown number more missing. Whilst the images in the media are in general somewhat confused (and I suspect that at least some reports are using archive images from other events), the best sources of information on the El Cambray Dos landslide are first this image from the BBC:
And second this video from CONRED, shot I assume from a drone, that provides an overhead view of the landslide:
The El Cambray Dos landslide was apparently triggered by heavy rainfall. Judging by the above image, this is a slide in poorly consolidated, weak materials. I do not know much about the about geology of this area (can anyone comment?), and I am not having much luck in finding detailed information. As far as I can tell the landslide occurred at this location, in the incised valley at the centre of the image:
This is a perspective view of the site, also from Google Earth:
The combination of a deeply-incised valley, a meandering river that is actively eroding its banks, weak rocks and intense rainfall appear to be responsible for this landslide, although we will need further information to be sure.
In the last large El Nino in 1997 and 1998, Central and South America were badly affected by rainfall-induced landslide. Given the magnitude of the El Nino currently developing, the next few months would seem to be a period of high risk.
Thanks for Jose Cepeda for highlighting the CONRED information and for his thoughts on the event.