Performance of HEC-HMS and SWAT to simulate streamflow in the sub-humid tropical Hemavathi catchment

Abstract The present study was conducted to examine the accuracy and applicability of hydrological models Soil Water Assessment Tool (SWAT) Hydrologic Engineering Center (HEC)- Modeling System (HMS) simulate streamflows. Models combined with ArcGIS interface have been used for in humid tropical Hemavathi catchment (5,427 square kilometer). critical focus streamflow analysis determine efficiency when were calibrated optimized using observed flows simulation Daily weather gauge stations data as inputs from 2014–2020 period. Other required run included land use/land cover (LU/LC) classes resulting remote sensing satellite imagery, soil map digital elevation model (DEM). For evaluating performance calibration, daily stream discharge outlet used. SWAT available water holding capacity by (SOL_AWC), curve number (CN) evaporation compensation factor (ESCO) are identified sensitive parameters. Initial abstraction (Ia) lag time (Tlag) significant parameters HEC-HMS calibration. subsequently adjusted autocalibration 2014–2017 minimize variations simulated values at (Akkihebbal). validated 2018–2020 period models. simulating streamflows during calibration validation phases, performances Nash-Sutcliffe (NSE) coefficient determination (R2). yielded high R2 NSE 0.85 0.82 comparisons time, suggesting that showed relatively good results compared model. Also, under modified LU/LC ungauged conditions, can be later future predictions. Overall, seems done well studies.