What happened

Saddle Dam D, an auxiliary embankment of the 410-megawatt Xe-Pian Xe-Namnoy hydropower project near Paksong in Attapeu Province, southern Laos, collapsed at around 20:00 local time on 23 July 2018 after torrential monsoon rainfall, which the project's joint-venture operator (Xe-Pian Xe-Namnoy Power Company, whose partners included SK Engineering and Construction, Korea Western Power, Ratchaburi Electricity Generating Holding and Lao Holding State Enterprise) said had filled the dam beyond capacity. Engineers had reportedly detected around 11 centimetres of subsidence at the dam's centre and flagged structural concerns at least a day before the collapse, and an evacuation order had been issued after cracks were discovered, but survivors said they received warnings only a few hours before the resulting flash flood struck. The collapse released a catastrophic flood that killed 71 people and displaced roughly 6,600 people across at least six villages, including Yai Thae, Hinlad, Ban Mai, Thasengchan, Tha Hin and Samong; the number reported missing fluctuated as high as 98-110 during the search-and-rescue effort before the final confirmed death toll was established. About 90% of the project's electricity output was contracted for export to Thailand. The disaster prompted extended calls from civil-society groups across the Mekong region for accountability, compensation and stronger hydropower dam-safety oversight. This is documented as a rainfall-triggered structural dam failure, not an attack.

When cited sources give different casualty, damage or spill figures for this event, they’re reported side by side above rather than merged into one number. See how confidence levels work.