Simulation of flood inundation of a low lying area of Ma'abar town in Yemen using remote sensing and GIS

Yemen is an arid to semi-arid country,which is now facing a very serious water shortage problem. at the same time,the country is remarkably exposed to more frequent disasters due to flooding. ma'abar town in yemen is among the most vulnerable places in yemen for flooding. accurate floodplain maps can be the most valuable tools for avoiding severe social and economic losses from floods. the main objective of this study is to generate a flood inundation map for the town and its surrounding area. the study consists of three component!: hydrology,hydraulics,and flood inundation mapping. the hydrologic component involves computing a multi- year design flows at ma'abar using hec-hms hydrological model. for the hydraulics component,the design flow is fed to hec-ras hydraulic model for estimating water surface profiles. the mapping component involves transferring water surface profiles into flood inundation extent. the inundated areas,delineated using the approach employed in this study,closely match with the area inundated during the observed historic flooding taken on the bases of available high flood marks observed on some buildings of the area and the evidence received from the people of the area.