Regional Flood Frequency Analysis Using L Moments for the Buyuk and Kucuk Menderes River Basins of Turkey

The main goal of this study was to determine regional probability distributions for the annual maximum flood data observed at 45 streamflow gauging sites in the Kucuk and Buyuk River Basins in Turkey using index flood L moments. Mann–Kendall trend analysis was previously applied to the streamflow gauging sites’s observed data, and dam effects were sought at all stations. Seven sites were omitted from the analysis because they were not unregulated or trends were present in the data. A regional analysis was performed on the remaining 36 sites, which satisfied the screening criteria of having a minimum record length of 10 years , representing unregulated natural flows, and passing the Mann–Kendall test at the 5% significance level. Data from the 36 streamflow gauging sites in the basins were screened using the discordancy measure ( Di ) . Homogeneity of the region was then tested using the L-moments heterogeneity measure by carrying out 500 simulations using the four parameter kappa distribution. Based on th...