Methods to Reduce the Risk of Flash Floods for Wadi El Ibrahimi, Eastern Desert, Egypt

Abstract

The hydrological regime of Wadi El Ibrahimi, located in the Eastern Desert, Egypt, is characterized by repeated flash floods, causing extensive damage to infrastructure, villages, and major roads, as well as several fatalities. Therefore, the main objective of this research is to find methods to reduce the damages caused by flash floods. In this study, data for a time period from 2000 to 2023, which had four storms, was used. The SMADA 6.3 program was used to create hydrographs for the four storms with varying
rainfall depths (29.63, 34.94, 11.56, and 18.11 mm) and return periods (2.4, 1.71, 1.5, and 1.33 years), respectively, in order to determine the maximum flow and runoff volume. The volume of runoff obtained varies from 0.243 million m3 to 0.07 million m3. Using ArcMap-software 10.3, Wadi El Ibrahimi was divided into six subbasins. David's method was used to determine hazard degrees for the
detected subbasins of Wadi El Ibrahimi. The hazard degrees can be divided into four categories: basins of very low hazard degree (subbasin 5); basins of moderate hazard degree (subbasin 3); basins of high hazard degree (subbasin 2, subbasin 4, and subbasin 6); and basins of very high hazard degree (subbasin 1). Recommended Construction of detention dams at the outlets of the main channels to allow recharging of groundwater aquifers and reduce the amount of lost water that runs to the Nile River. Also, the installation of cisterns at the exits of the main channels allows for the storage of large quantities of surface water, as well as the installation of well-turbulent rain stations for more accurate estimates.