Digital elevation model for flood hazards analysis in complex terrain: Case study from Jeddah, Saudi Arabia

• DOI: 10.1016/j.jag.2023.103330
• Publication Date: 2023-04-29T21:49:49Z
• Authors: Ahmed M. AL-Areeq; Hatim O. Sharif; S.I. Abba; Shakhawat Chowdhury; Mohammed Al-Suwaiyan; Mohammed Benaafi; Mohamed A. Yassin; Isam H. Aljundi
• Keywords: Wadi; Elevation (ballistics)

Global Digital Elevation Models (GDEMs) have been increasingly used to assess the risk of flooding worldwide. However, their effectiveness and performance flood models in areas with complex terrain, such as Jeddah, Saudi Arabia, not comprehensively studied. This study aims compare five distinct − 30-m SRTM, ASTER, 90-m MERIT, 10 m Sentinel-1 DEM, 12.5 ALOSPALSAR - estimating inundation extent depth Jeddah watershed, including three dams. Both hydrological hydraulic modeling approaches were utilized achieve this objective. The findings revealed that all produced similar watershed boundaries mountain area (Wadi Qaws), except for ALOS-PALSAR, which generated a different boundary from previous reports studies. GDEMs failed accurately delineate drainage one dams, SRTM ALOS-PALSAR. Moreover, ASTER products provided closest estimates ground observations, producing peak discharges 114.1 m3/s 110 m3/s, respectively. For entire encompassing mountain, urban, coastal areas, demonstrated significant differences boundary, streams, outlet location, discharge at outlet. In addition, each GDEM's map was significantly distinct. Overall, results suggest outperformed other area.