Discharge modeling in part of Ambika River basin using SWAT model

Abstract

Discharge or Runoff is a very important factor of hydrologic cycle and it is useful for watershed management
for conservation and development of natural resources and its management. Till now most useful and appropriate
method for surface Runoff estimation is Soil Conservation Services-Curve Number (SCS-CN). Remote sensing and
Geographical Information System (GIS) is effective tool for extracting watershed parameter and use of mathematical tool
is the current trend for hydrologic evaluation of watershed. In present study, QSWAT having an interface with QGIS
software was selected for estimation of Runoff for small watershed of Ambika river basin of Gujarat, India. Various
parameters Digital Elevation Model (DEM), Landuse/Landcover (LULC) and NBSSLUP soil data and temporal data for
temperature and precipitation was used as input for the model to predict runoff at the catchment outlet. The performance
of the model in terms of simulated discharge was evaluated using statistical method and compared simulated monthly
flow with the observed monthly flow values from 2000 to 2006 to a significant extent. The simulated flows for five years
of recorded and results are encouraging. The correlation coefficient for the monthly discharge was obtained as 0.753,
0.936, 0.536, 0.939 and 0.506.