Flood Hazard Micro Zonation from a Geomatic Perspective on Vitilevu Island, Fiji

Abstract

Flash floods in the rural and urban areas led to high level of water in the roads, houses and agricultural land which create numerous problems such as traffic problems, water-borne diseases, and damages of roads and collapse of buildings. It is impossible to reduce the occurrence of floods but it is possible to identify the risks zone and employ measures to reduce its disastrous effect. The aim of this paper is to demarcate the flood risk zone of Vitilevu Island into ‘low’, ‘moderate’, and ‘high’ classes. In order to fulfil this, we use hydrology, site-soil-geology, and geomorphology and SRTM DEM data. The method used is called Analytical Hierarchical Process (AHP) to ascertain the relative impact weight of flood causative parameters to get the flood hazard index (FHI). The outcome was the flood hazard Zone of Vitilevu Island showing selected infrastructures vulnerable to different zone of flood. Thus, this present study contributes conceptually, contextually and temporally towards the use of GIS and urban planning disciplines.