Rainfall-Runoff Simulation using Remote Sensing and GIS Tool (SWAT Model) (A Case Study: Xebanghieng Basin in Lao PDR)

Abstract

The Arc-SWAT model was applied to the Xebanghieng (XB) river Basin for modeling of the hydrological water balance. The primary objective of this study was to assess the water availability in the basin and feasibility of the SWAT model for prediction of main stream flow which is available for gauging site and which is not available so far for gauging site in the Basin. The water balance modeling was performed on annual, monthly and daily basis using spatial and temporal data of surface runoff. The model was calibrated and validated in main stream in lower part of XB River using SUFI-2. The sensitive analysis of the model to sub basin delineation and HRU( hydrologic response unit) definition thresholds showed that the flow is more sensitive to the HRU definition thresholds than sub basin discretization effect. SUFI-2 gave good result during calibration period. Coefficient of determination (R²) criterion, Nash and Sutcliffe efficiency (NSE) were adopted to see performance of the model during calibration and validation period.  Study indicated that due to high intensity of precipitation and good water retention capacity, the study area has high potential for agricultural activities.

Keywords: Xebanghieng River, GIS, SWAT, Runoff