Flood hazard zoning and risk assessment for Bandar Segamat sustainability using analytical hierarchy process (AHP)

Flood is common natural disaster that occurs during heavy rainfall. It has cause devastating impact towards lives, infrastructures, properties and environment landscape. In recent flooding event in Malaysia on December 2014, it is reported that about 200 000 people are affected, which double up the number of people affected during flooding event on December 2006 and January 2007. Thus, the demand for flood risk assessment becomes crucial. This paper explores the application of Analytical Hierarchy Process (AHP) in flood risk assessment for Bandar Segamat sustainability. Several criterions has been chosen to be analyzed which include rainfall distribution, slope, distance from river, land use, drainage density and road density. These criterions were assigned with weightage that has been given by the experts in order to determine the most contributed factors towards flooding. ArcGIS 10 developed by Environmental Systems Research Institute (ESRI) was used for processing the data. The results of this analysis were overlaid with the flood vulnerable element such as land use, buildings and population. Results indicated that 50.75km² of 190.38km² of the study area is prone to flood. Sg. Segamat, Gemereh and Pagoh sub-districts of Segamat were revealed as having the most area to be at high risk being flooded which is about 16.85km², 10.7km² and 7.74km². This study emphasizes one of the alternatives of many presence flood risk assessments nowadays that can help the authorities to devise strategies in dealing with flooding.