Dona Juana: a large garbage landslide in Bogota

On Tuesday 28 April  2020 a large garbage landslide occurred at the Dona Juana waste site on the outskirts of Bogota in Colombia.  Fortunately there were no casualties.  News reports suggest that it had a volume of about 60,000 cubic metres.  The images are quite spectacular:-

The 28 April 2020 Dona Juana garbage slide in Bogota. Image via BluRadio. Note the backhoes at the foot of the landslide, which provide a scale.

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Side view of the Dona Juana garbage landslide on 28 April 2020. Image tweeted by @OscarFlorezO.

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RTE has a news report about the landslide, providing some useful background.  News reports in Colombia suggest that concerns have been raised in recent weeks about the performance of the private sector operator of this extremely large landfill site, although there is little detail as to the concerns.

Fortunately the images suggest that although this slide has a large area the depth is not particularly great.  The slide appears to be translational in nature, which raises the question as to whether the process of emplacing the waste has created a weak surface that has allowed sliding to occur.  Whatever the cause, garbage piles are always made by people, so the failure is ultimately human error of one sort or another.

Interestingly, the Dona Juana landfill site underwent a much larger landslide in 1997, with an estimated mass of about 700,000 tonnes. There is a paper on ResearchGate providing details of that event.  In that case the landslide appears to have been quite deep-seated, and to have been a consequence of poor management of the leachate (water that has percolated through, and been generated within, the waste) and the biogas generated within the garbage.  A failure to provide adequate drainage pathways allowed high pore water pressures to be generated, promoting instability.

I suspect that the cause of the failure at Dona Juana this week is rather different, but is just as unacceptable.