Evaluation of Land Development Impact on a tropical Watershed Hydrology Using Remote Sensing and GIS

Understanding how the land use change influence the river basin hydrology will enable planners to formulate policies to minimize the undesirable effects of future land use changes. Land cover changes increase impervious ground surfaces, decrease infiltration rate and increase runoff rate, hence causing low base flow during the dry seasons. Efficient tools such as satellite remote sensing and Geographic Information System (GIS) are currently being used to manage the limited water resources. The need for spatial and temporal land-cover change detection at a larger scale makes satellite imagery the most cost effective, efficient and reliable source of data. The ability of GIS makes it an important and efficient tool for spatial hydrologic modeling. In this study, Satellite data and GIS were integrated with a spatial hydrological model to evaluate the impacts of land development in the Upper Bernam River Basin of Malaysia. HEC-1 (Hydrologic Engineering Center) model was calibrated and validated using actual flow data from the outlet of the watershed. The model performance was checked by means of four criteria viz., mean absolute error (MAE), root mean square error (RMSE), Theil’s coefficient (U) and coefficient of determination (R2) obtaining values of 0.14, 0.18, 0.097, and 0.86, respectively. From th