Regional flood frequency analysis by L-Moments method in Halil Roud Basin (Jiroft)

Among natural hazards, flood is perhaps the most destructive one which imposes high damage to human communities, facilities, industrial and agricultural areas. Frequency analysis and our knowledge of the probability of occurrence or return period of floods will help us in planning and risk reduction of the floods. In this study, the method of L-moments was applied for regional flood frequency analysis in Halil Rood basin, Jiroft. For regional homogeneity and finding discordant stations, two H and D measurements showed that the region is homogeneous without discordant station. After selecting at-site distribution, the goodness-of-fit-test, ZDIST showed the LN3 distribution to be the best regional distribution. The area of watershed was also found the parameter of multiple regressions which is used for estimation of flood with different return periods at ungauged watersheds.