mahnaz edirsh

According to the annual damages of flood in Dez river catchment and the lack of information about water quantity which contribute substantially to the flow of the river in the middle sub-basins, the aim of this study was to determine the contribution of sub-basins flow to total basin flood and to identify areas of flooding potential. So, the standard precipitation index was calculated to identify the wettest period in the region. Then, the whole basin was divided into 11 sub-basins and subsequently a rainfall-runoff simulation was carried out by using WMS software. Finally, the contribution of each sub-basin to the outlet flood peak was quantified by successively eliminating sub-basins from the simulation process. The result showed that the Dokouheh sub-basin by decreasing the peak flow (40 percent) is the most effective region in flooding. Then, Hamidabaad with 35 percent and Dez dam with 15 percent are the sub-basins with more flood potential, respectively. In addition, to eliminate the effect of sub-basin area, prioritization was done corresponding to the contribution at the outlet per unit area of sub-basins. Dokouheh with 29 percent, Hamidabaad with 25 percent and Dezful with 15 percent were given first, second, and third rank, respectively