Numerical Modeling of Flow through a Breached Levee and during Levee Closure

Excessive precipitation, fast snow melting, and storm surges due to hurricanes often result in levee breaching and inland flooding which devastates social facilities, residential properties, environment quality and threatens human lives. To enhance the resilience of society, it is important and necessary to study levee breaching flows and develop technologies for repairing damaged levees effectively during the flood. In this study, computational simulations were conducted using a finite element based two-dimensional and depth-integrated numerical model, CCHE2D. Data of a scaled levee breaching physical model were used to validate the computational model. The flood and levee breaching occurred during the Hurricane Katrina in New Orleans, LA, were studied in the Hydraulic Lab, and the measured flow distribution in the vicinity of the breached levee was simulated. The numerical model resulted in good agreement with the measured flow velocity and water surface elevation distribution. The computational model such validated was also applied to simulate the breach closure processes conducted in the physical model. This capability could help emergency managers and engineers to close breached levees more effectively. The practice of placing sand bags into the flow and closing the breaching was mimicked by using a graphic user interface.