Flash floods mitigation and assessment of groundwater possibilities using remote sensing and GIS applications: Sharm El Sheikh, South Sinai, Egypt

Abstract Background In arid and hyper arid regions, flash floods directly affect human life and ecosystem balance through soil erosion and sediment exchange between different watersheds. The present study provides an integrated approach using remote sensing and geophysical data, multiple thematic layers, and field investigations to mitigate the flash flood hazard and explore the groundwater potentiality in Sharm El Sheikh area, Egypt, where devastating flash flood hazards and shortage in water supply are critical problems against the development of the touristic city. Results A new flood hazard index (FHI) is introduced using the morphometric parameters and multiple thematic layers for the investigated hydrographic basins. The FHI ranges between 55.2 (low) and 73 (very high). The resulted surface runoff from a single event (59 mm/day) reached up to 7.96 mm while the total runoff volume reached up to 20.23 (106) m3 representing about 13.5 % of the total rainfall. Hydrogeologically, the Miocene sediments represent the main aquifer, which is cut by four recognized faults providing opportunities for enhanced groundwater recharge. The integrated geophysical datasets (aeromagnetic and vertical electrical sounding) and borehole data indicate that the subsurface sedimentary succession reaches up to 200 m of Quaternary and Miocene sediments. Conclusions The present study introduces a comprehensive system to mitigate floods and increase the opportunity of groundwater recharge that could protect and enhance the environment under arid conditions. The presented approach can be applied in any arid and hyper arid regions with the same conditions. Graphical abstract