Better understanding of the flood hazard phenomenon and its potential consequences in our society is crucial for the development of flood control polices, risk reduction projects, and other types of flood management strategies. This study focuses on how two different ArcHydro models used to predict the floodplain extent and assess the vulnerability of Dongola city that may affect the estimation of potential flood damage. The stream Water System Elevation (WSE) from point WSE measurement is used as first model which creates two temporary output files. In order to determine the flooding extent, the water heights from Dongola gauge station were analyzed to identify the area of floodplain. Floodplain has been delineated and was found to be 566 m on average on the east bank, while it was 404 m on average on the west bank.

Keywords: Flood plain, geographic information systems (GIS), river banks.