CONFIRMEDDate confidence: CONFIRMEDStated as firmHow firmly the source words the date: confirmed, scheduled, estimated, delayed or unverified.Show all CONFIRMED pins78% CONFIDENCEOverall confidence: 78%How well the pin's source and references back up its dates.Weighted average of how firmly 4 references, the source included, support the pin's start and end times; a reference counts half as much for every 180 days older than the newestShow all pins at 75% confidence or better
Wikipedia's[1][2][3] article and timeline date the collapse to 8 August 1975 (the failure spans 8-10 August); Weather Underground gives the night of 7-8 August and Wikipedia's Typhoon Nina article says the storm moved southwest on 8 August after causing the collapse.Typhoon Nina's record rainfall burst the Banqiao Dam on the Ru River in Henan on 8 August 1975, triggering the failure of dozens of other dams in the deadliest dam disaster in history.
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