Utility of 2D/3D visualization methods in analyzing and disseminating flood information

Flooding is a leading natural cause of physical damage and loss of life, and substantial effort has been invested in improving the prediction of intensity and timing of flooding along major river systems. However, for these predictions to have the greatest impact on public behavior and response, improved visualization techniques must be implemented to reveal critical flood information in a useful and efficient manner. Utilizing HEC-RAS hydraulic model simulations along the Pascagoula River in southern Mississippi, currently produced operationally at the Lower Mississippi River Forecast Center (LMRFC), the utility of using various 2D and 3D techniques for viewing water level data are presented. This includes methods for viewing and interpreting extent, location, intensity, and timing of flood waves through the river channel, as well as local-scale hydraulic effects resulting from engineering structures or backwater flow. The utility of the various visualization methods is outlined with regard to information dissemination, but the utility for analysis and interpretation of model output by forecasters is also addressed. Early results indicate that the improved capabilities for viewing and analyzing water extent and depth relative to surrounding terrain and structures provides a more effective and efficient method for displaying model simulations, and provides a platform for additional analysis using existing hydraulic variables available in HEC-RAS output. This includes a more robust assessment of ensemble simulations and more rapid verification of model output with remotely sensed data. A software product that implements these 2D and 3D visualization techniques for hydrologic applications is currently being developed at the Geosystems Research Institute (GRI) at Mississippi State University, with future plans including a stand-alone package for operational use at the LMRFC and other river forecast centers.