期刊名称：Science et changements planétaires / Sécheresse
印刷版ISSN：1147-7806
电子版ISSN：1777-5922
出版年度：2013
卷号：24
期号：3
页码：171-181
DOI：10.1684/sec.2013.0389
出版社：John Libbey Eurotext
摘要：Figures See all figures Authors Mohammed El Bastawesy , Turki Habeebullah , Khalid Balkhair , Ibrahim Ascoura National Authority for Remote Sensing and Space Sciences (NARSS) 23 Joseph Tito Street El-Nozha El-Gedida Egypt, Umm Al Qura University Geography Department PO Box 715 Makkah 21421 Saudi Arabia, Umm Al Qura University The Institute of Custodian of The Two Holy Mosques for Hajj and Omrah PO Box 6287 Makkah 21955 Saudi Arabia, King Abdul Aziz University Faculty of Earth Sciences PO Box 9027 Jeddah 21413 Saudi Arabia Key words: flash flood, GIS, hydrology, Makkah, remote sensing, Saudi Arabia, wadi DOI : 10.1684/sec.2013.0389 Page(s) : 171-81 Published in: 2013 This paper assesses the hydrology of flash floods in urbanized dryland catchments of Makkah. The original landscape and land cover of the catchments have witnessed significant changes over the past few decades, during which most of the alluvial channels and the mountain foot slopes have been covered by urban sprawl. The occasional threat of flash floods has prompted the development of a mitigation measure including installation of a rainfall-sewage system, culverts, small dams upstream, and lining of the levees of some channels. However, the latest flash flood event of the 30th of December, 2010 resulted in fatalities and demonstrated the insufficiency of the current mitigation system to control flash floods. The runoff coefficient was estimated from the opportunistic observations and measurements of the flow discharge parameters for the latest event, in addition to the recorded rainfall parameters. The digital elevation model (DEM) was analysed using the Geographical Information System (GIS) to determine the spatially distributed time-area zones of the catchment, which were used to simulate the runoff hydrographs under certain runoff coefficients and designed storms of long return periods. The development of urban areas at the expense of the alluvial channels has resulted in a significant surge of total runoff and peak discharges as well as and the reduction of transmission loss into the underlying alluvium. Consequently, it is estimated that the 50-year simulated runoff parameters will far exceed the designed discharge capacities of installed culverts and lined channels, which may endanger certain urban areas in Makkah. The integrated management strategy of flash floods in Makkah should include the construction of several small dams on the fingertips of alluvial channels to reduce sediment and water influx to the urban areas and the conveying alluvial channels. Additionally, the levees of active channels should be controlled and maintained to convey the estimated flow magnitudes to outlet.
关键词：flash flood; GIS; hydrology; Makkah; remote sensing; Saudi Arabia; wadi
