Abstract
A retarding basin, that temporarily stores storm water to reduce downstream flow rate, is one of the most effective countermeasures to mitigate existing downstream flooding problems. Effectiveness of the basin is dependent on design of an overflow levee. Experimental works have been commonly employed for the overflow levee design, because the flows around the levee are very difficult to be handled by theoretical and/or numerical methods. The objective of this study is to demonstrate that the numerical model, which comprises the finite volume method based on unstructured grid using FDS technique, along with appropriate boundary conditions is able to calculate the stage-discharge relationship for retarding basins built in river bends with good accuracy.
