Application of satellite image processing and GIS-Spatial modeling for mapping urban areas prone to flash floods in Qena governorate, Egypt

摘要

Flash floods in Egypt are considered frequent meteorological natural hazards. Qena is one of the most Egyptian governorates prone to flash floods. Various flash floods events hit Qena from 1954 till 2016. Flash floods occurred in Qena on 28th October 2016 inundated houses and roads, generated losses in lives, damages to private and public property. The intensive rainfall coupled with the rapid urban expansion in Qena and along the Nile Valley could worsen the situation. Despite, the destructive impacts of the flash floods in Qena, flash floods can be used as a valuable source of fresh water as the study area is classified as an arid zone and characterized with the fresh-water shortage. Integration of remotely sensed data with the Analytical Hierarchy Process and Geographic Information Systems spatial modeling presented valuable analysis techniques in this study. The present study focused on mapping the spatial distribution of flash floods vulnerability in Qena's urban areas. Ten indicators were used to analyze the flood floods namely; rainfall, soil, geology, slope, elevation, flow direction, drainage network, land cover, total population, and population density. The results revealed that Qena, Qus, Naqadah, and Dishna urban districts are the most vulnerable to flash floods and located in the very high zone with 25.3%, 14.9%, 12.3%, and 9.8% respectively. The total population situated at very high and high vulnerability zone reached represents 7.66% and 43.36% of the total population. The obtained results considered crucial information for decision-makers for future effective flash floods hazards mitigation, assessment management, planning, and sustainable development.