Using a new flood modeling and mapping method named PRIMo (Parallel Raster Inundation Model) to show in nearly house-by-house detail the impact of a 100-year flood, the study found existing assessments to be wildly inaccurate and the aging waterway control system to be woefully inadequate for coping with a massive deluge.

"We knew the paper would get some attention because we're saying that the number of people at risk is 30 times greater than the federally defined flood plains would suggest," says lead author Brett Sanders, UC Irvine professor of civil and environmental engineering. "On top of that, we identified glaring racial and economic inequalities in the flooding risks that residents face. … Sanders' co-authors include fellow Department of Civil and Environmental Engineering faculty [and Professor] Amir AghaKouchak, along with research specialist Jochen Schubert and grad student Daniel Kahl; [Professor] Steven J. Davis of the Department of Earth System Science; [Professor] Richard A. Matthew and [Assistant Professor] Nicola Ulibarri of the Department of Urban Planning and Public Policy; and researchers from UC Riverside, UC San Diego and the University of Miami. Read More