Computational Simulation of Levee Breeching and Flooding of the Midwest Flood in Mississippi River, 2008
 
Yafei Jia, Ph.D.

Catastrophic flooding is a major security concern in the United States. Failure of dams, levees and flood gates of water infrastructures such as reservoirs, lakes, rivers and coastal water will cause losses of many lives, billions of dollars in property damage and environment degradations. Although most of the rivers are confined within manmade levee systems, these infrastructures are in great need to be improved and strengthened.

In June, 2008, the levees of the Mississippi River were breached by a large flood. More than 22 breached levees flooded many areas along the River in several days with 24 fatalities; thousands of people were affected and lost their homes, many industries and farmers in 51 counties of 5 states (Illinois, Missouri, Wisconsin, Iowa, and Minnesota) lost their products and ability to recover from this disaster.

Recently, NCCHE has been supported by the US Department of Home Land Security to develop technologies for studying flood propagations due to dam break, levee breaching and flood associated morphologic response and chemical contamination.  The Midwest Flood 2008 was selected as a test example to demonstrate the developed computational capabilities. CCHE2D finite element model for free surface flows was modified to compute the flood. The levee breaching and flood propagation were computed using a hybrid explicit/implicit solution method which greatly speeded up the computation and reduced the total computation time.  Satellite imageries were used to define the locations of the breaching, Manning’s resistance parameter and to estimate breaching times in this reach of the River. Eight breaching were observed in the satellite images. 
The computed flood propagation process and that observed are illustrated in the attached animations which can be played using Google Earth over the actual flooded area (Canton City, Mo.). The computed and observed flooding processes agree quite well. The computed results have to be simplified to generate the animations to have the file size limited. Detailed animations of the simulation results are available if interested.
The computational modeling system is supported with a user friendly graphic user interface and can be deployed quickly for flood emergency management purposes. Other capabilities of the system such as simulating water contamination, water quality, geomorphic response and levee closuring, etc. will be made available soon.
 

Download link for Midwest Flood KMZ file