Hydrological Modeling in A Semi-Arid Region Using HEC-HMS

In this study, the Hydrologic Engineering Centre's Hydrologic Modeling System (HEC-HMS) model was employed to simulate runoff in the semi-arid region of northwestern China, specifically the Hailiutu watershed. The Hydrologic Engineering Centre's Geospatial Hydrologic Modeling Extension (HEC-GeoHMS) was used in conjunction with ArcHydro tools in an ArcMap geographical information system (GIS) environment to create input files of the catchment physical characteristics for the HMS model. The model was calibrated for the time period of 1978-1992. The results showed that the model systematically underestimated winter and spring hydrographs as well as a few summer flows. This was due to the discrepancy between the nonlinear rainfall-runoff response in the watershed and the linear structure of the Soil Moisture Accounting (SMA) model used. Also, the results pointed out that, due to data unavailability on hydraulic engineering in the Hailiutu watershed, the model faced challenges in simulating runoff properly and therefore could not be validated. Ultimately, the model's general performance in simulating runoff in the Hailiutu watershed was found unsatisfactory.