14 March 2022
Ampang: a deadly urban landslide in Malaysia
On Thursday 10 March 2022 a large urban landslide occurred at Taman Bukit Permai 2 in Ampang, Malaysia, killing four people and injuring a further individual. The landslide has been extensively reported in the media in Malaysia. The two best images of the landslide that I have found are these two. The first was published in Utusan Malaysia:-
Whilst the second was published in My Metro:-
The landslide was triggered by heavy rainfall, which is quite unusual for this time of year in Malaysia. It appears that the immediate trigger was an extremely heavy, short duration rainfall event, although unseasonal rainfall has reportedly been falling for several weeks.
There is a video of the landslide occurring, which has been posted to Twitter:
Landslide in Ampang, 15 houses affected, three feared buried alivehttps://t.co/g1NlaKtqnN
10 March 2022
AMPANG JAYA: Some residents at Taman Bukit Permai were injured after a landslide covered several homes in Pandan Indah here today. pic.twitter.com/ABg68cpksh
— Eugene CHUNG (@eugenechung) March 10, 2022
The video appears to show a rotational failure in the upper part of the slope. The main track is essentially planar – it appears that the main part of the debris has moved as a flow, fortunately with only moderate mobility. The failure appears to have been in deeply weathered (residual) soil or in fill (see below). Interestingly, there are some reports that local residents had seen signs of deformation on the slope in the weeks leading up to the failure. It is also interesting to note that in the first image posted above another large landslide is visible on the slope.
The location of the landslide is 3.107, 101.762. At first glance the slope looks to be natural, but Google Earth is very revealing. The image below was collected in 2004:-
The image above appears to indicate that this was an engineered (i.e. modified) slope. It will be interesting to discover the design specification for this slope, the maintenance regime (especially with regard to drainage) and the monitoring that has been undertaken since. Hong Kong’s remarkably successful slope safety system has been based upon careful management of engineered slopes such as this.