Method of flash flood rainfall indicator determination based on rainfall-runoff charts based on rainfall-runoff charts
Xu Shaojun1 Jiang Yansheng1 Ma Beiping2 Luo Qian2
1.Flood Control and Drought Relief Headquarters Office of Hubei Province ,Wuhan 430071;
2.Middle Yangtze-River Bureau of Hydrological and Water Resources Survey in Yangtze-River Water Resources Commission Ministry
Abstract:The rainfall threshold is an important indicator used to establish early warning system and making prevention plans for flash floods disasters. Based on a review of commonly used methods for estimating rainfall threshold in flash flood forecasting, the interpolation of correlation curve between rainfall and runoff method is proposed in this study, combining with investigation and evaluation of flash flood. The method is applied to calculate the rainfall threshold of the Zhangjiahe watershed in Hubei Province. First of all, the method considers the influence of antecedent rainfall to gain rainfall thresholds by interpolating the correlation curve using the corresponding flow of the warning water level. The correlation chart is proposed, according to a certain period of rainfall and the formed flood peak flow. Taking advantages of the data-driven statistical and inductive methods and the physical process-based hydrologic hydraulic methods, the calculation method in this paper is practical and desirable for prevention flash flood disaster.