Assessment of flood risk by using geospatial techniques in Wabi Shebele River Sub-basin, West Hararghe Zone, southeastern Ethiopia
Biratu Bobo Merga, Feye Lama Mamo, Mitiku Badasa Moisa, Firdisa Sadeta Tiye, Dessalegn Obsi Gemeda
Abstract
Abstract Floods are produced as a result of several factors such as human-induced land-use changes, topographic conditions, and climate change. This study aimed to assess flood risk using geographic information system-based multi-criteria evaluation techniques in the Wabi Shebele River Sub-basin. Six parameters, namely, soil type, slope, land use and land cover, proximity to rivers, rainfall, and elevation, were used. The eigenvector of weight for each factor was computed in IDRISI Selva 17.0. Results show that the study area was subjected to a very high 527.31 km 2 (9.42%), high 2133.66 km 2 (38.12%), moderate 1906.44 km 2 (34.06%), low 847.35 km 2 (15.14%), and a very low 182.54 km 2 (3.26%) flood risk, respectively. Results reveal that the Wabi Shebele River Sub-basin is highly vulnerable to flooding. This study assists policymakers with regard to land-use planning. To reduce the effects of flood risk, integrated watershed management must be implemented in the study area.