Flow accumulation is among the most important criteria in determining flood hazard regions (Kazakis et al. 2015). Flooding occurs in regions with a lot of water (Tehrany et al. 2015). Flow accumulation is often lower for the lower classes of rivers in the upstream. In the downstream of the watershed, many tributaries join the main channel, which increases the flow accumulation and the flood risk. Therefore, high flow accumulation can be found in the downstream region of the study area. An increase in flow accumulation exacerbates the occurrence of flood (Abdel Hamid et al. 2020) (Figure 3 (g)). Flow accumulation is often lower for the lower classes of rivers in the upstream. In the downstream of the catchment, many tributaries join the main channel, which increases the flow accumulation and the flood risk. Therefore, high flow accumulation can be found in the downstream region of the study area. The flow accumulation and the area coverage of the Bilate catchment are given in Table 9.