Study region: Wadi Tayyibah is located in south Sinai, Egypt, in a region called Abou Zenima, and
it is used to develop this study.
Study focus: Flash floods tremendously impact many facets of human life due to their destructive
consequences and the costs associated with mitigating efforts. This study aims to evaluate the
harvesting of Runoff by delineating the watersheds using the Hydrologic Engineering Center-1
(HEC-1) model and ArcGIS software in trying to benefit from it in different ways. All morphometric parameters of the basin were considered, and the risk degree of the different sub-basins
was determined. The suitable locations of dams were identified using a Geographical Information System (GIS) using the basin’s morphometric characteristics.
New hydrological insights for the region: The study proposed a total number of eight dams, including
five dams that were recommended for sub-basin (1) and three dams in sub-basin (4), while subbasins (2) and (3) are not suitable locations to build dams according to the contour map of Wadi
Tayyibah. Results indicate that, based on the constructed flash flood hazard maps and the basin’s
detailed morphometric characteristics, the best locations of dams are Dam (3) in sub-basin (1) and
Dam (7) in sub-basin (4), where the runoff volume reached 3.13 million cubic meters (Mm3) and
5.56 Mm3 for return period 100, respectively. This study is useful for decision-makers and designers for using morphometric parameters and flash flood hazard degree maps to select dam
locations. Also, the cost-benefit analysis for using the morphometric parameters is required to be
investigated.