Integrated flood vulnerability assessment of villages in the Waimanu River Catchment in the South Pacific: the case of Viti Levu, Fiji

This paper uses a holistic approach within a catchment scale, through the application of both climatic and non-climatic parameters, to analyze the impacts of river floods on the human security needs of rural riverine communities in the Waimanu Catchment situated in Nausori, Fiji. Consideration of both climatic and non-climatic factors is required since non-climatic factors could be controlled to build resilience against floods. The indicator-based flood vulnerability index methodology is applicable worldwide, but the indicators used in this study were specifically related to the Pacific Island context. In the context of fluvial flood vulnerability, effects of land management and climate change are not mutually exclusive of each other. Consequently, vulnerability assessments should consider the connection between people’s actions and ecosystems for the entire catchment area since upstream land use practices influence flood vulnerabilities downstream. In our research, a community-based flood vulnerability index system in conjunction with rainfall variability and land use assessments was used to quantitatively and qualitatively analyze the flood vulnerability, and it was found that increased rainfall, poor agricultural practices, gravel extraction, and improper waste management predominantly increased the exposure and sensitivity of midstream and downstream communities to river floods by modifying river morphology. Midstream communities in the Waimanu Catchment were most vulnerable to river floods due to their very low adaptive capacity in terms of poor ecosystem health and lack of natural resources to cope with the subsequent impacts of floods, being most sensitive to changes in land use and land cover