Risk Information for Floodplain Management

Abstract

The United States began structural flood control in the 1930s and added complementary nonstructural measures in the 1960s. Nevertheless, national flood damage totals continue to increase. Reversal of this trend will require better communication among regulatory agencies, experts assessing risk, and floodplain occupants. Modern technology provides tools to measure specific risks and communicate the hazards of property loss and personal danger to individuals able to act to reduce the losses. One problem with the existing communication based on a safety standard tied to the 100‐yr floodplain is that some locations in the 100‐yr floodplain are only subject to trivial damage by shallow flooding, while other locations outside that magic boundary are subject to major devastation and threats of drowning by floods that could be as common as the true 25‐yr event. Systematic estimation and dissemination of the risk of economic loss can reduce flood losses, vary community programs with the hazard to life and property, and help every floodplain occupant accommodate more effectively with his site‐specific problem.