Risk Study Of Flood Storage In Ponds

The flood has the characteristics of benefit and disaster which will lead huge losses to people's lives and property if improperly used, so it is necessary to analyze the risk in course of exploit and use. Flood storage by ponds is one of the ways for flood resource utilization in middle and lower reaches of rivers, the risk assessment and control will provide a basis with safe and effective use of regional flood resources.First of all, the risk control measures of flood resources utilization which includes "long-term planning, pre-plan, real-time control" is introduced, and the principles, objectives and main contents are described in the paper.The risk identification method is proposed, which identifies the risk factors and risk factors losses during the use of flood resources. The analytic hierarchy process and principal component analysis are applied to screen the main risk factors of use of ponds flood storage on the basis of risk factors identification result for use of flood resources. It includes:uncertain risk of benefit losses, uncertain risk of calculation and parameter, risk of long-term rainfall-runoff forecasting errors, risk of scheduling decision as well as risk of implementation.The assessment method of flood resources utilization is proposed. On the basis of time & space dimension, a two-dimensional risk rate estimation model of ponds flood storage, which takes Cile Pond in Baicheng City, Jilin Province, China as an example, is established. The model is solved based on practical to get the risk rate of flood storage during different flood times in situation with and without control measures. The risk factors result is applied to implement 200mm of rainfall to flood the late for obtaining the risk loss value of during different flood storage times in situation with and without control measures in Cile Pond. The study indicates that the risk level of ponds flood storage with control measures is smaller than that without control measures, and the former is defined light risk, the latter is defined between small and heavy one. On the whole, the risk law is:in space dimension, the greater the flood storage capacity, the greater the risk is, whereas smaller; in time dimension, the earlier the storage, the greater the risk is. The risk loss with control measures changed little, such as in late August, the minimum is 0.793×106 yuan, the maximum is 1.653×106 yuan, the amplitude is 0.860×106 yuan; the risk loss without control measures changed great, such as in late August, the minimum is 0.001×106 yuan, the maximum is 4.870×106 yuan, the amplitude is 4.869×106 yuan, which is about 5.7 times of the one with control measures. When the flood storage is large, the risk loss with control measures is obviously smaller than that without control measures.