Geospatial risk assessment of flash floods in Nuweiba area, Egypt

Nuweiba sits on a flood plain between the Sinai Mountain and the Gulf of Aqaba. Flash floods pose significant threats to socio-economic development in the region. This study assessed flash floods risk in the greater Nuweiba area in support of mitigation planning. Our approach evaluated topographic, hydrological, and geological factors holistically to rank areas of high, median, and low flash floods risk along the Wadi Watir. Data from field surveys, Enhanced Thematic Mapper (ETM+) imagery, and Shuttle Radar Terrain Model (SRTM) were analyzed through digital image processing and spatial analysis to characterize lithology, soil types, land cover, and hydrological morphometrics. The morphometric parameters were used to evaluate the most sensitive sub-basins for flooding and create the flash flood susceptibility map. Soil Conservation Service (SCS) Rainfall-Runoff model was used to estimate hydrological responses at ungauged catchments, including runoff depth, lag time, and peak discharge. We spatially integrated all the risk factors and created a flash floods risk map as the practical geospatial assessment of flash flood risk in the greater Nuweiba area.