Banqiao Dam: The Deadliest Dam Failure in History

In August 1975, Typhoon Nina stalled over central China and dropped more than a year's worth of rain in a single day. Before the night was over, the Banqiao Dam and sixty-one others had failed, in what remains the deadliest dam failure in recorded history. But the disaster didn't start with the rain. It started in the 1950s, with an engineer named Chen Xing who looked at the plans for these dams and said they were dangerous. He was purged for it. Twenty years later, the government that exiled him would send him to Beijing to authorize blowing up their own flood-control structures to save the survivors. This is the story of the arithmetic of a reservoir, the political culture that ignored it, and the people caught downstream when the iron dam finally broke. Chapters: 00:00 Cold Open 00:57 Huai River Basin 01:58 Dam Building 02:32 Embankment Dam 03:11 The Iron Dam 03:49 The Water Budget 05:36 The Great Leap Forward 06:53 Suya Lake 08:50 Typhoon Nina 11:56 Overtopping 12:41 The Failures Begin 13:13 The Sky Collapses 15:05 Exploding the Dams 15:52 The People 19:04 Chen Xing 20:20 Banqiao Rebuilt 20:47 Conclusion 21:24 Outro Sources and further reading: Yi Si, "The World's Most Catastrophic Dam Failures," in Dai Qing (ed.), The River Dragon Has Come! (M.E. Sharpe, 1998) Human Rights Watch, "The Three Gorges Dam in China," Vol. 7 No. 1, February 1995 Association of State Dam Safety Officials, Banqiao Dam case study Qian Gang, "The Great 1975 Zhumadian Flood" U.S. Bureau of Reclamation, Reclamation Consequence Estimating Methodology (2015) A note on sources: the record on this disaster is thinner and more contested than usual, and the death toll in particular was a state secret for decades. Where the numbers are disputed, I've tried to show you exactly how and why in the video rather than pick one for effect. Satellite typhoon imagery: representative modern imagery from a GEO-KOMPSAT satellite. Credit the Cooperative Institute for Research in the Atmosphere at Colorado State University, the Korea Meteorological Administration, and the National Meteorological Satellite Center (CSU/CIRA & KMA/NMSC).