Comprehensive hazard susceptibility assessment in Port Sudan city using AHP: emphasizing flash flood risk, soil moisture, and salinity dynamics

Natural hazards threaten ecosystems, societies, and infrastructure, especially in rapidly urbanizing areas. Port Sudan City, on the Red Sea coast near the Red Sea Hills, is vulnerable to flash floods, soil collapse from salinity, and variable soil moisture, affecting sustainable land use. This study develops a hazard susceptibility assessment using the Analytic Hierarchy Process (AHP) and geospatial analysis. Factors including elevation, slope, curvature, geology, land use/cover (LULC), drainage density, salinity, and soil moisture were integrated into an AHP-based multi-criteria framework. Satellite data (Landsat 8 OLI, Sentinel−2) provided indices such as NDVI, LSE, LST, and SMI. Four factor groups were analyzed: (i) hydro-meteorological factors driving floods; (ii) soil-related factors causing infrastructure damage; (iii) terrain factors increasing rockfall risk; and (iv) LULC and geology-related factors. An integrated hazard map was validated with field surveys and lab analyses. Flood risk had the highest AHP weight, followed by salinity and soil moisture. Southern areas, including the airport and Bashair Terminal, are highly flood-prone; the 2024 Arbaat Dam collapse increased northern flood risk. Shoreline areas face salinity and moisture hazards, while western steep terrain is prone to rockfalls. Results highlight the need for updated hazard maps, better drainage, and sustainable land-use planning.