Abstract: To explore the causes of the “2020·6·12” flash flood disaster in Zheng'an County, Guizhou Province, data was collected and site surveys were conducted. The disaster, flood and rain conditions were analyzed. The dynamic process of flood inundation was simulated and verified using two-dimensional flow model software based on two-dimensional shallow water equations. The causes of the flash flood disaster were obtained: 1) The special topography provided basic conditions for the disaster; 2) Short-duration heavy rainfall superimposed on high previous cumulative rainfall was the key factor in inducing disaster; 3) The contradiction between the inadequate flood control capacity of the river course and excessive peak discharge made disasters inevitable; 4) Many non-residents and floating population, women and children with poor self-rescue ability, and people with low risk-avoidance awareness greatly increased disaster risks. On this basis, some measures to prevent and control flash flood disasters were proposed such as scientific top-level design, improvement of mass monitoring system and prevention of flash flood disaster, and detailed dynamic management of flood control and disaster reduction.

Key words: flash flood disaster, inundated by floods, analysis of causes, disaster enlightenment, Zheng'an County, Guizhou Province