Halil-River Basin Regional Flood Frequency Analysis Based on L-moment Approach

摘要

In the present study L-moment approach was used for flood frequency analysis in Halil-River basin. To identify the homogeneous regions, the Ward hierarchical cluster method was used. For independent testing of the cluster in the station for homogeneity, site data information was used. The Halil-River basins were divided in to two regions (region A and B) and parameters of the regional frequency distribution were evaluated by L-moment ratios. For the selection of appropriate distributions, L-moment diagram, goodness of fit test and plotting position methods were used. The results showed that in Halil-River basin, Generalized Pareto distribution for region A, Generalized extreme values, Pearson type III, Lognormal, Generalized Logistic and Generalized Pareto for region B are appropriate distributions. The relative Root Mean Square Error (rRMSE) between observed and estimated data in all stations was calculated. The results showed a good agreement between observed and estimated data. Regional model evaluated for determination of mean flood discharge magnitude by liner and multiple regression method.