Identifying best combination of methodologies for event-based hydrological modeling using HEC-HMS software: a case study on the Panchganga River basin, India

摘要

Abstract The present study focuses on identifying the best combination of methodologies from the selected methods of loss, transform and routing given in HEC-HMS for identifying the best suited event-based hydrological model for the Panchganga River basin, Kolhapur District, Maharashtra, India. The model development consists of delineating the catchment using QGIS 3.10.1 and delineated catchment is further processed in the HEC-HMS. By performing permutation and combination of selected loss methods namely Green and Ampt and SCS curve number (SCS-CN), transform methods namely SCS unit hydrograph (SCS-UH) and Clark UH and routing methods namely Muskingum and Muskingum-Cunge, eight different models are developed. The developed models are calibrated for the rainfall event thatoccurred during 22/7/2014 to 4/8/2014 and validated for the rainfall event that occurred dufring 5/7/2016 to 20/7/2016. The performances of eight models are evaluated by using statistical indices namely Nash–Sutcliffe index (NSI), percent difference in peak flows (Dp ) and deviation in runoff volumes (Dv ). On the basis of statistical indices, best combination of loss, transform and routing methods is selected. On the basis of evaluated statistical indices for different models corresponding to validation, it is found that, combination of SCS-CN, Clark UH and Muskingum-Cunge method has NSI value 0.81 and very low values of Dv (7.77) and Dp (0.61), so this combination of methodologies is identified as the best combination for the event-based modeling of the Panchganga River basin. The simulated discharge values obtained from the best combination of methodologies corresponding to validation are found to be in good agreement with corresponding observed discharge values at Wadgane and Ichalkaranji gauging stations.