Fluvial Stage-discharge Rating of Wadi Hanifa Main Channel

Abstract

Recent cross-sectional survey of Wadi Hanifa reach, within Arriyadh city, has been analyzed. The analysis includes the estimation of carrying capacity, possible maximum scour depth and sediment transport capacity of the selected reaches. A well-known resistance equation has been adopted and modified to a simple form in order to be used in the present analysis. The modified resistance equation has been used to calculate the mean velocity through the channel sections. In addition, a sediment transport equation has been applied for the prediction of transport capacity of the various sections. Results show that the existing drainage sections of Wadi Hanifa channel reach under study have adequate carrying capacity under existing bank-full conditions, but these reaches are subject to bed erosion even in low flow situations. Regarding sediment transport rate, it can be estimated that the channel flow has a relatively low range of bed material concentration. Finally, stage-discharge curves for various sections have been developed. Based on stage-discharge rating data of various sections, water surface profile and sediment-rating curve of Wadi Hanifa have been developed.