Use of Space Technology and GIS in Seasonal Water Course System (Case of Gash River Basin)

Large areas of the African Region have experienced widespread flooding in the last years. The hydrologic models can help reduce the human and economic losses in these regions by providing improved monitoring and forecast information to guide relief activities. Hydrologic models need to be calibrated for the specific region where they will be used to produce best results. Gash River is a frequent source of tracer to the inhabitants in the areas around it. Flooding of the Gash is now approximately one in five years. The recent 2003 catastrophic flood of kassala Town is an example. The objectives of this study are to explore the use of wide stream flow model (GeoSFM) developed by the USGS to manage the floods of a seasonal streams like the Gash. The model uses the widely available public domain data from remote sensing to produce river flow forecast. The data used include DEM, Soil data, land use, land cover and climatological data. The data available splitted in to two parts one used for calibration and other for verification. The model calibration was done manually to reproduce the observed flows and produce parameters in their physical limits. It was found that the model reproduces the observed hydrographs closely especially the peak value