Flood susceptibility mapping in the Bilate catchment, Ethiopia

Abstract

Flood susceptibility mapping plays a key role in planning flood mitigation. Floods may not be avoidable due to future climate changes. The Bilate catchment in Ethiopia is vulnerable to flood disasters and it is used as a case study in this project. The analytical hierarchy process (AHP) under multi-criteria decision analysis (MCDA) is used to develop the flood susceptibility map of the Bilate catchment. It was accordingly found that factors such as slope, rainfall, land use/land cover (LULC), elevation, topographic wetness index (TWI), soil type (ST), sediment transport index (STI), drainage density (DD), stream power index (SPI), and distance from the river (DR) have significant effects on the flood intensity in the Bilate catchment. The output maps were developed using ArcGIS. The prepared flood susceptibility map was classified into five classes such as very low, low, moderate, high, and very high covering 9.3, 32.6, 41.2, 10.8, and 6.1% of the area, respectively. The flood susceptibility map reported in this research is a great resource for relevant parties, including government and non-governmental organizations, to evaluate the impacts of flooding in the Bilate catchment and throughout the nation. The flood identified in this research may also be used as a reference to flood-related studies.

Flood Impacts on Household Livelihoods and Its Mitigation Strategies: Focus of Gelana Woreda, Oromia, Ethiopia

“…The area's altitude or elevation signi cantly determines ood hazards. Altitude in uences temperature and precipitation, which in turn impacts how surface water ows (Edamo, Bushira, et al, 2022). The reclassifying tools of ArcMap 10.8 were used to construct all the processes needed to establish the in uence of elevation factors on ood risk from DEMs.…”

“…Land use and land cover should be considered when determining which locations are vulnerable to ooding (Edamo, Bushira, et al, 2022). According to the rede ned land use/land cover suitability map for oods, the percentages of the entire region with very high, high, medium, low, and very low levels of ood danger are 34%, 0.5%, 2.5%, 52.7%, and 9.3%, respectively (Table 12).…”

Flood Susceptibility Mapping in the Municipality of Bayombong, Province of Nueva Vizcaya, Philippines

“…Flood is a recurring natural hazard that adversely affects the lives and properties of many people around the world. It can be attributed to natural and man-made factors such as climate change, increasing precipitation, deforestation, population growth and urbanization (Edamo et al 2022). In the Philippines, major floods were caused by the prevalence of typhoons and heavy rainfalls.…”

“…AHP is a decision-making procedure that combines multiplechoice criteria into hierarchy and these criteria are ranked based on their impacts using Pairwise Comparison Matrix (Yahaya, 2010). Many studies related to flood susceptibility mapping (Edamo et al, 2022;Cabrera et al, 2020) uses the AHP as a multi-criteria decision analysis strategy to map flood-prone zones.…”