Precipitation-induced inland flood causes more property damage in the United States than any other natural disaster. On average, the U.S. experiences ground-up losses from precipitation-induced inland flood of more than $25 billion annually, according to the AIR Inland Flood Model. With continued development (much of it in flood-prone areas), rising property values and increasing numbers of extreme wet-weather events, this figure is expected to increase.

To illustrate the high risk of loss from inland flood in the United States, AIR created a megadisaster scenario that features an entire year of precipitation-induced inland flood events from the AIR U.S. inland flood model's stochastic catalog, with an aggregate ground-up loss of $100.8 billion — a loss level that has an exceedance probability (EP) of one percent (100-year return period). The scenario includes a wide range of inland flood events, with on- and off-floodplain flooding in several major river basins, short- and long-duration storm systems, and failed flood defenses. As shown in Figure 1, every state in the contiguous United States plus the District of Columbia experienced inland flood losses during the modeled year.

Inland floods in the United States