The Flood Inundation Mapping of Kampung Sungai Kertil in Kuala Muda, Kedah

Abstract

This study focuses on using a geomatics-based flood modelling as a tool to visualise and communicate predicted flood levels in Kampung Sungai Kertil in Kuala Muda, Kedah. Flooding is a recurring problem in the area, causing significant damage and disruptions to human settlements, infrastructure, and the economy. This research aims to develop an effective flood model that enhances the accuracy of flood map preparation and facilitates a better understanding of flood risks. The research utilises a combination of hydrological modelling and geographic information systems (GIS) to analyse flood-prone areas in a case study region. In ArcGIS, the Hec-GeoRAS extension extracts geometric information from Digital Elevation Model (DEM) and imports data from HEC-RAS for flood inundation mapping. Data from the SRTM DEM is used in this case study. In order to accurately simulate floods and analyse water levels using the steady flow simulation approach, RAS layers that include crucial hydraulic parameters are created within HEC-RAS. The model results demonstrate that higher discharge scenarios (up to 150 m³/s) produce substantially larger inundation extents, identifying seven settlements within the predicted flood-prone area.The study advances a thorough knowledge of regions vulnerable to flooding by creating maps of flood potential, which supports preventative flood management measures. The results underscore the importance of flood modelling in improving the precision of flood map creation and bolstering efficient flood control strategies.