American Council of Engineering Companies of Texas





		Sophisticated Flood Plain Modeling Saves Money For Local Citizens





		In 2004, FEMA began a re-mapping of the Brazos River which dramatically affected flood levels along the river in the Richmond, Texas area. These higher flood levels resulted in significant flows overtopping the river and draining away from the river channel. HEC-RAS, the one-dimensional hydraulic used in re-mapping effort, is limited in its ability to simulate these types of complicated overbank flow scenarios.

		The engineering firm believed that peak water levels predicted by the FEMA models, were not correct in the vicinity of the River’s Edge subdivision, which is located in the overbank area of the Brazos. To provide a more accurate simulation, the firm conducted an analysis utilizing state-of-the art two- dimensional (2D) modeling software to compute peak flood elevations in the overbank areas. This sophisticated 2D modeling analysis yielded lower flood levels in the Rivers Edge area, which, in turn, will lower citizens’ flood insurance premiums and the developer’s costs for future mitigation.


		The 2D Modeling – The Future of Sophisticated Flood Plain Modeling Project was designed by Costello, Inc. based in Houston, Texas. This project was a gold medal winner in the 2010 ACEC Texas Engineering Excellence Awards Competition.