GIS-based river flood hazard mapping in urban area (a case study in Kayu Ara river basin, Malaysia)

In the past decades, thousands of lives have been lost, directly or indirectly, by flooding. In fact, of all natural hazards, floods pose the most widely distributed natural hazard to life today. Sungai Kayu Ara river basin which is located in the west part of the Kuala Lumpur in Malaysia was the case study of this research. In order to perform river flood hazard mapping HEC-HMS and HEC-RAS were utilized as hydrologic and hydraulic models, respectively. The generated river flood hazard was based on water depth and flow velocity maps which were prepared according to hydraulic model results in GIS environment. The results show that, magnitude of rainfall event (ARI) and river basin land-use development condition have significant influences on the river flood hazard maps pattern. Moreover, magnitude of rainfall event caused more influences on the river flood hazard map in comparison with land-use development condition for Sungai Kayu Ara river basin.