What can be learned from Taiwan's Matai'an Barrier Lake disaster?

On Sept. 23, 2025, at 2:50 p.m., a historic downpour caused the Matai'an Barrier Lake in Hualien to overflow and burst its banks. Within minutes, 60 million tons of water and debris swept through the villages of Guangfu Township, flooding streets, damaging over 1,600 homes and killing at least 19 people. What caused the collapse of the world's largest rainfall-formed landslide dam? Two experts who monitored the lake reveal the science, the challenges, and the difficult decisions behind Taiwan's disaster response -- from the earthquake that weakened the slopes to the race to evacuate those in danger.