STREAMFLOW QUANTIFICATION USING SWAT ON SUBCATCHMENT OF NARMADA RIVER BASIN IN MADHYA PRADESH

Abstract

Water is an essential element for the existence of all living things, including flora, wildlife, and industrial activities. In recent years, there has been a tremendous increase in the demand for water for domestic, commercial, industrial, and agricultural applications. Recently, many distributed and quasi-distributed watershed models based on the deterministic approach have been widely utilised for the assessment of hydrological scenarios and to implement the alternative management techniques in the area like water resources development and management. In previous studies, the applicability of SWAT model has been tested at large scale and small-scale basins to build the commendable watershed management strategies. As per the availability of hydrological models in the open-source domain, a semi-distributed and continuous time step based hydrological model viz. SWAT has been employed in this research study to perform the rainfall-runoff modeling in Banjar River basin under varying climatic and terrain characteristics. Banjar River is a tributary of Narmada River basin. Banjar and other sub-basins that cover parts of Madhya Pradesh and Chhattisgarh states are covering the selected catchment area of 1520 km2. In this study, the model was simulated utilizing various datasets such as DEM, LULC map, soil map, and climate variables during 2000 to 2009. Model calibration/validation has been done in SWATCUP tool on the daily and monthly time steps utilizing the (Sequential Uncertainty Fitting Approach) SUFI2 with reference to observed flow (2000-2009). During the daily calibration, the SWAT model usually performs well as the model strength was tested by several statistical functions viz. Nash Sutcliffe efficiency (NSE), Coefficient of determination (R²), and Percentage bias (PBIAS) recorded as 0.37, 0.39, and -9, respectively. However, the monthly calibration results show a significant improvement in the R² (recorded as 0.65). SWAT CUP is successfully utilized in the optimization of Banjar River parameters and exploring the uncertainty involved in modeling inputs and outputs.