Flow over spillways or underneath gates has a tremendous amount of potential energy, which is converted into kinetic energy downstream control structures. This energy should be dissipated to prevent the possibility of excessive scouring of the downstream waterway bed, minimize erosion and undermining of structures, which endanger the structure safety. In this paper, an experimental study was conducted to predict the scour geometry downstream a sloped spillway and to minimize the scour using a

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... epped spillway with certain arrangements. It was found that the using of stepped spillway instead of the sloped one reduced the relative scour depth and increased the relative energy loss and the spillway with three steps gave the smallest value of scour depth. The dimensional analysis was employed to drive expressions correlating the different variables affecting the scour phenomena. Prediction equations were developed using the multiple linear regression (MLR) to model the relative scour depth Ds/yup and the relative the relative energy loss ∆E/Eup. A good agreement was obtained between the predicted and the measured values. Finally, this study yielded conclusions which can be recommended in the design procedure and practical applications.