Mapping Flood Extent Using a Simple DEM-Inundation Model

Abstract

A grid-based one-dimensional digital elevation model (DEM)-inundation model has been developed as a tool for flood extent mapping on floodplains. The validity and accuracy of the model have been assessed through comparison of modeled results with those derived from the widely used standard and complex 1-D Hydrologic Engineering Center-River Analysis System (HEC-RAS) model and verification against the September 1999 flood on the lower Tar River floodplain, North Carolina. The two models are comparable in accuracy. With its simple implementation and ease of parameterization, the DEM-inundation model is a potential alternative to the HEC-RAS model.