Runoff simulation using the SWAT model and SUFI-2 algorithm in Ghod catchment of upper Bhima river basin Patil Mangal1,*, Kothari M.1, Gorantiwar S.D.2, Singh P.K.1 1Department of Soil and Water Engineering, College of Technology and Engineering, MPUAT, Udaipur-313001 2Department of Irrigation and Drainage Engineering, Dr A.S.CAE&T, MPKV, Rahuri-413722 *Corresponding author: E-mail: mangalpatil43@gmail.com (Mangal Patil)
Online published on 26 June, 2019. Abstract In this study, the soil and water assessment tool (SWAT) was used to simulate the runoff in Ghod catchment of upper Bhima river basin for the period 1997–2015. Model calibration and validation were performed for monthly time periods using sequential uncertainty fitting version 2 (SUFI-2) within the SWAT-calibration uncertainty program (SWAT-CUP) using 19 parameters which have been selected from past literature. Calibration outputs for the period 2000–2010 with 3 years warm-up period (1997–1999) showed a good correlation between observed and simulated values with the P-factor and R-factor found 0.59 and 0.56, respectively, nash sutcliff efficiency (NSE) = 0.88 and correlation coefficient (R2) = 0.89. During the validation period (2011–2015), the P-factor and R-factor found 0.52 and 0.63, respectively, and the NSE and R2 values were found 0.72 and 0.74, respectively. Following calibration, the overall effect of each parameter used was ranked using a global sensitivity function within SWAT-CUP. From the analysis, curve number (CN2) was found to be the most sensitive parameter with absolute t-value of 18.50 and p-value of 0.00 to simulate the stream-flow of the Ghod catchment. The deep aquifer percolation fraction (RCHRG_DP) was observed as the least sensitive parameter with t-statistic and pvalue of 0.02 and 0.97, respectively. It was concluded from the study that the coupling of the SWAT and SWAT-CUP made the calibration process quicker and reliable to simulate local hydrology within the watershed. Top Keywords Calibration, SUFI-2, SWAT, SWAT-CUP, Validation and Sensitivity analysis. Top |