Assessment of flood risk due to storm surge in coastal bayous using dynamic hydraulic modeling
Ray, J. Tyler
Master of Science
The purpose of this study is to analyze the combined effects of storm surge and inland rainfall on the floodplain of a coastal bayou in the Houston area using dynamic hydraulic modeling. HEC-RAS, a one dimensional flow model, was run for both the steady and unsteady states in order to analyze the linkage between inland flooding and storm surge. First, the steady model was run to give a basic understanding of the watershed. The unsteady HEC-RAS model was then evaluated in the unsteady state which allowed both rainfall and storm surge from Hurricane Ike to be introduced dynamically. This allowed for a more accurate representation of the timing of flooding characteristics of Horsepen Bayou, and the modeled hydrographs generated an excellent match against measured data in Horsepen Bayou. Using this model it was discovered that the timing of both rainfall and storm surge play a significant role in the magnitude of flooding.
Hydrology; Geological engineering; Civil engineering