Flood modeling using HEC-HMS and EasyFit software (case study: Abriz basin, Kaldan station, Delfard river)

The HEC-HMS model is one of the most reliable hydrological models for estimating rainfall -watersheds, which is widely used to estimate the volume and discharge of floods. In this research, with thehelp of the capabilities of this model and with the statistics and information of the meteorological andhydrometric stations of the Shiro Jiroft watershed in the period of ۳۲ years from ۱۹۸۳ to ۲۰۱۹ water year, weestimate and simulate the precipitation-runoff process and recalibrate the observational data and The basinwas calculated. Next, with the help of EasyFit software, the return period of the maximum flood flow wascalculated. For modeling, a rainfall-runoff event was chosen on ۲۹ and ۳۰ Bahman of the water year ۲۰۱۶. Inthe process of model calculations, in order to calculate basin runoff losses, the SCS network method wasused to convert the excess precipitation process into surface flow, and the SCS unit hydrograph method wasused. In the section of the meteorological model, a customized histograph method is used to analyze therainfall data. The results showed that the Nash-Santcliffe coefficient of Kaldan station is equal to ۰.۷ and theexplanation coefficient is equal to ۰.۹۳, which is a relatively high accuracy in simulating the hydrologicalbehavior of the Shore Jiroft river basin.

کلیدواژه ها:

HEC-HMS model ، EasyFit ، flood ، watershed ، Kaldan station