Drainage Analysis of Mountainous Watersheds in Ras Al Khaimah Emirate, UAE
Abstract – Many Wadis in the Arab Emirates (UAE) are active during rainy periods. Geomorphologically, the UAE is composed of mountains, gravel plains, sand dunes, and coastal zones. The runoff generation in these Wadis represents a complex phenomenon because of the topography of drainage basin. Morphological parameters were estimated and analyzed for the surface runoff generation and flooding possibility of twelve catchments in Ras Al Khaimah area of UAE. Hydrologic Engineering Center-Hydrologic Modeling System model is used to estimate the water yield in Wadi Al Bih due to rainfall events. Simulated results were compared with the observed water storage data of several historical storm events for the calibration of the model. The obtained results were compared with the observed yield and are found accurate and within an average of error 10%. Rainfall-runoff/yield curves were developed based on the duration and intensity of rainfall distribution. These curves can be used for prediction of surface water runoff and water storage in dams due to different rainfall events.
Keywords: Geomorphology, Watershed, Flood, Rainfall-runoff, United Arab Emirates.