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 from June 1938 to January 1947 created by the Chinese National Army's intentional destruction of dikes (levees) on the Yellow River in Huayuankou, Henan Province. The first wave of floods hit Zhongmu County on 13 June 1938.

The flood acted as a scorched-earth defensive line in the Second Sino-Japanese War.^[1][2][3] There were three long-term strategic intents. Firstly, the flood in Henan safeguarded the Shaanxi section of the Longhai railway, the major northwest traffic where the Soviet Union sent their military supplies to the Chinese National Army from August 1937 to March 1941.^[4][5] Secondly, the inundated land and railway made it difficult for the Japanese Army to mobilize into Shaanxi, thereby preventing them from entering the Sichuan basin, where the wartime capital of Chongqing and the southwestern home front was located.^[6] Thirdly, the floods in Henan and Anhui crushed the tracks and bridges of the Beijing–Wuhan Railway, Tianjin–Pukou Railway and Longhai Railway, thereby preventing the Japanese Army from mobilizing their machines and troops across the theaters of North China, Central China and Northwest China.^[7] The short term strategic intent was to stop the quick mobilization of Japanese Army from North China into the Battle of Wuhan.^{[7][8][9][10]}

The flood achieved the above strategic intent; 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 Henan, Anhui and Jiangsu provinces,^[11][12][13] while a total of 400,000 to 500,000 civilians died from drowning, famine and plague.^[14][15] The Yellow River was diverted to a new course over swathes of farmland until the repair of the dykes in January 1947. Five million civilians lived on such inundated land until 1947.^[15] Inspired by the strategic outcome, dykes elsewhere in China, especially along the Yangtze, were later destroyed by the Chinese and the Japanese.^[1]