1938 Yellow River flood

The 1938 Yellow River flood (simplified Chinese: 花园口决堤事件; traditional Chinese: 花園口決堤事件; pinyin: Huāyuánkǒu Juédī Shìjiàn; lit. 'Huayuankou Dam Burst Incident') was a man-made flood in China from June 1938 to January 1947 created by the intentional destruction of levees on the Yellow River in Huayuankou, Henan, by the National Revolutionary Army (NRA) during the Second Sino-Japanese War. The first wave of floods hit Zhongmu County on 13 June 1938.

NRA commanders intended the flood to act as a scorched earth defensive line against the Imperial Japanese Armed Forces. There were three long-term strategic intentions behind the decision to cause the flooding: firstly, the flood in Henan safeguarded the Guanzhong section of the Longhai railway, a major northwestern route used by the Soviet Union to send supplies to the NRA from August 1937 to March 1941. Secondly, the flooding of significant portions of land and railway sections made it difficult for the Japanese military to enter Shaanxi, thereby preventing them from invading the Sichuan basin, where the Chinese wartime capital of Chongqing and China's southwestern home front were located. Thirdly, the floods in Henan and Anhui destroyed much of the tracks and bridges of the Beijing–Wuhan railway, the Tianjin–Pukou railway and the Longhai railway, thereby preventing the Japanese from effectively moving their forces across Northern and Central China. In the short term, the NRA aimed to use the flood to halt the rapid transit of Japanese units from Northern China to areas near Wuhan.

The flood achieved the strategic intentions set by NRA commanders; in particular, the Japanese Operation 5 never captured Shaanxi, Sichuan or Chongqing. However, the flood came at enormous human cost, economic damages and environmental impact; in the immediate aftermath, 30,000 to 89,000 civilians drowned in the provinces of Henan, Anhui and Jiangsu, while a total of 400,000 to 500,000 civilians died from drowning, famine and plague.