Simulation of Levee Breach due to Overtopping Using Two- and Three-Dimensional Models

Abstract

Accurate prediction of levee-breach characteristics is necessary for emergency preparedness to minimize loss of life and property due to levee failure. Three-dimensional computational fluid dynamics software, FLOW-3D Hydro, is used to predict the breach characteristics of noncohesive earthen levees. The model is validated using experimental data of small-scale levee breaches from the literature. The results show that FLOW-3D Hydro accurately predicts the time evolution of breach characteristics, including breach hydrograph and water depth in the channel adjacent to the breach. The results of the three-dimensional model are compared to the numerical results of the two-dimensional depth-averaged model developed at the University of South Carolina. The comparison shows that the results of the three-dimensional model agree more closely with the experimental measurements as compared to those of the two-dimensional model. This information should be helpful for developing flood risk management strategies by providing more accurate predictions of levee breach characteristics for the design and safety assessment of levee systems.