Nadma report: Cause of Batang Kali landslide likely ‘natural’, not enough evidence to blame human activities

The landslide near Batang Kali, Malaysia, which tragically claimed the lives of dozens of campers, including children, last year, has been determined to have been "likely" caused by "natural failure," according to the investigation report by the Natural Disaster Management Agency (Nadma). While human activities were considered a potential factor, there was no concrete evidence to support this theory. Some environmentalists had raised concerns about development in the hilly area, suggesting it might have contributed to the slope's collapse.

Nadma's investigation found no substantial anthropocenic causes for the landslide, even though human activities may have had some impact. Routine slope and road maintenance in the area were conducted as scheduled just before the landslide occurred.

The disaster occurred in December 2022, with 31 people losing their lives in the landslide, which struck after nearly five days of heavy rainfall, including 13 children. Most of the victims were camping on a popular site owned by a commercial orchard. The landslide was attributed to embankment failure in an area approximately 500 meters long, 200 meters wide, and 8 meters deep, involving the movement of approximately 450,000 square meters of soil.

Two significant slope failures were identified during the incident, the first of which occurred due to high water saturation, creating a collapse zone with an average depth of 14 meters and a length of 120 meters. The debris reached a campsite located approximately 550 meters away. Subsequently, the debris formed an artificial temporary dam at the toe of the failed slope, leading to a combination of a rotational slide and debris flow. The primary contributing factors to such events were identified as heavy rainfall and hydrogeology, linked to changes in the underground water regime.