Communicating Flood Risk to the Public
"As the Houston region grapples to recover from Hurricane Harvey and prepare for future storms, one continuing point of contention is whether the floodplain maps illustrate a realistic level of flood risk.
A report prepared by the City of Houston indicates that during Harvey, a larger number of structures flooded outside of the 100-year and 500-year floodplains than within the floodplains. Because flood insurance is not mandatory for homes outside the 100-year floodplain, most of the impacted homeowners are now facing costly repairs without insurance benefits. Frustrated homeowners who thought they would be safe from flooding are now questioning the accuracy of these maps.
What hasn’t been transparent is that the flood risk mapping process includes unavoidable underlying uncertainty and limitations. Even if the maps are updated with new information, the underlying uncertainty will always exist. Rather than relying on the accuracy of the maps, the community must work toward a more complete and robust understanding of flood risk and the maps that portray this risk."