Flash flood modeling and mitigation of Al-Hussainiyah area, Makkah, Saudi Arabia

• DOI: 10.1007/s12517-021-08400-9
• Publication Date: 2021-09-22T08:03:44Z
• Authors: Safwat S. Gabr; Ibrahim A. Alkhaldy; Waleed A. El-Saoud; Turki M. Habeebullah
• Keywords: 13. Climate action; 11. Sustainability; 15. Life on land; 01 natural sciences; 6. Clean water; 0105 earth and related environmental sciences

The topographic nature of Makkah, Saudi Arabia, hinders most of the urban development and expansion activities except on the foothills of the mountains, where most of the already developed and ongoing/planned new settlements occur. Al-Hussainiyah area is one of many unplanned settlements that has been constructed along the course of Wadi Uranah flood plain. The area has been affected by many flash floods events over the past years, which resulted in a considerable amount of property damage. Rapid mitigation measures for such area are important to avoid future flash flood losses. The current research uses all the available fieldwork, meteorological, and remote sensing data to predict the surface water runoffs from modeled rainfall storms of returning periods of 10, 25, 50, and 100 years. The modeling results revealed that the average surface water runoffs from the modeled storms are 194.5, 247.7, 284.8, and 318 million m3 running at maximum speeds of 7578, 9610, 11,014.3, and 12,260.9 m3/s respectively. The results also indicate that the current flood course of Wadi Uranah at Al-Hussainiyah area will not be able to accommodate these volumes of water at its given speeds and will case devastated damage to the settlements of the area unless this course is expanded to accommodate the volume of water generated from at least one of the designed storms.