Zoning of flood potential in Gorchay Ramian watershed

Flood risk management deals with cases such as; analysis, management and declining the social impact of flooding. Gorchay Ramian watershed due to the countless floods was selected for this study. The purpose of this research was identifying factors, which affect zoning of flooding potential and flooding potential prioritization of sub-basins by using AHP method. As deficiencies caused because of being subjective and selective attention of experts in this field have been plunged, also integrating sub-basins prioritization with respect to the weight of each indicator in achieving the objectives can be provided. Analyzing the final weight from AHP approach has shown that, hydrometorological criterion with weight of 0.65 compare to morphometric criterion is more important in this study area and rainfall intensity for the time of concentration sub-criterion was the most important of these criteria. Based on the final ranking, flooding potential zone constitute almost 27 percent portion of the catchment, which most of them are situated in mountainous and upland areas, this is due to the high weight of two sub-criteria of rainfall intensity for the time of concentration and precipitation with return period of 25 years in comparison with other sub-basins. The proposed method in this study, in addition to improving the accuracy of identifying flooding potential areas, can help in understanding the processes involved in catchment.