Mitigation of urban waterlogging from flash floods hazards in vulnerable watersheds

Abstract

Study regionThe Aswan region is a vast plateau in the South of Egypt located 150 m above mean sea level (AMSL). Within this region, the tourist city of Aswan is Egypt’s southernmost city, located on the east bank of the Nile River. Study focusThe occurrence of flash floods can severely impact low-lying and densely populated areas. Therefore, highly vulnerable areas require effective mitigation measures to guarantee public safety and preserve archeological sites of great importance. This study investigates the interaction between the soil, surface water, and groundwater in the Aswan region of Egypt. Based on the rainfall analysis and the watershed hydrology, six different scenarios were run using the MODFLOW and Watershed Modeling System (WMS) software, which simulated rainfall recurrence intervals of 2, 5, 10, 25, 50 and 100 years. New hydrological insights for the regionThe model's results indicated that an increase in the recurrence interval produced a rise in the groundwater level (GWL) up to 8.82 m (AMSL). Therefore, constructing three dams was proposed as a solution at the three basins of Al- Haytah, Al-Kimab, and Umm-Buwayrat. The proposed solution allows the storage of large volumes of water upstream. It mitigates GWL's rise within and near Aswan City. The presented study can be applied to vulnerable watersheds in arid and semi-arid regions. It can help policymakers to integrate additional sustainable solutions into construction dams and their implementation in development plans.