Ministry of Natural Resources confirms road subsidence near Vajira Hospital caused by soil collapse

Chayanan Pakdeejit, Permanent Secretary at the Ministry of Natural Resources and Environment, along with experts from the Department of Mineral Resources, visited the scene of the road subsidence in front of Vajira Hospital in Bangkok’s Dusit District on the morning of September 24. This followed an initial collapse at 07:13 am, which expanded by 07:45 am, causing power poles and vehicles to fall into the sinkhole.

Initial investigations revealed that the area is composed of Bangkok Clay, a layer of dense, approximately 25-metre thick clay, covered by a fill layer that serves as the road base. The subsidence occurred in a linear pattern along the road, which differs from natural sinkholes that tend to form in a circular shape. As such, it was concluded that this incident is unrelated to geological factors.

Chayanan said the main cause of the subsidence is attributed to the collapse of the fill layer, triggered by several factors, including a burst water pipe, heavy rainfall that eroded the soil and created voids underground, and the ongoing construction of the subway line in the area, which may have impacted soil stability.

The Ministry has instructed the Department of Mineral Resources to coordinate with all relevant agencies to ensure accurate information is provided to the public and to reduce panic.