This paper presents a simple and affordable approach to flood hazard assessment in a region where primary
data are scarce. Using a multicriteria decision analysis (MCDA) approach coupled with GIS layers for
elevation, catchments, land-use, slope, distance from channel, and soil types, we model the spatial extent of
flood hazard in the Nadi River basin in western Fiji. Based on the flood hazard model results we assess risk to
flood hazards in the greater Nadi area. This is carried out using 2007 census data and building location data
obtained from aerial photography. The flood model reveals that the highest hazard areas in Nadi are the
Narewa, Sikituru and Yavusania villages followed by the Nadi central business district (Nadi CBD). Closer
examination of the data suggests that the Nadi River is not the only flood vector in the area. Several poorly
designed storm drains also present a hazard since they get clogged by rubbish and cannot properly evacuate
runoff thus creating water build-up. We conclude that the MCDA approach provides a simple and effective
means to model flood hazard using basic GIS data. This type of model can help decision makers focus their
flood risk awareness efforts, and gives important insights to disaster management authorities.