Flooding in the U.S. is a pervasive, year-round threat, affecting Americans nationwide. And although flooding from large-scale extreme weather events such as hurricanes tend to grab headlines, they are only part of the nation’s flood story. According to a new analysis of storm data by The Pew Charitable Trusts, other events, including heavy rains and rapid snow and ice melt, cause varying degrees of flooding across the country, often inundating homes and businesses, compromising infrastructure, and impairing local economies.
Pew’s analysis of the National Oceanic and Atmospheric Administration’s Storm Events Database, which includes reports from a variety of government and nongovernment sources, revealed three themes about the frequency, type, and geographic extent of flood events across the country over the past two decades.
Since 2000, at least one flood occurred in the U.S. on nearly 300 days per year, on average. The NOAA database also shows that all 50 states and the District of Columbia were affected by flooding in 2021. This ever-present risk underscores the need for comprehensive resilience planning that can help safeguard communities and the critical infrastructure they depend on daily, such as roadways, schools, and hospitals.
The Storm Events Database shows that even during the June-November Atlantic hurricane season, the majority of days with flooding were not reported as associated with tropical cyclones but involved other events such as flash floods, lakeshore floods, and seiches (significant waves typically driven by strong winds or rapid changes in atmospheric pressure). This can pose a constant threat to the lives of Americans nationwide.
Although some of the more damaging and widespread floods in recent memory occurred along our nation’s coasts during hurricane season, NOAA’s Storm Events Database shows that where it rains, it can flood. In fact, flooding was reported almost as often inland as it was along the coast from June to November over the past two decades.
Flooding continues to be the most common and costly natural disaster in the country, with flood-related disasters causing more than $85 billion in damage and economic losses in 2021 alone. These events weaken and destroy infrastructure and upend the livelihoods of families and businesses. To reduce these costs and better prepare Americans, all levels of government must take action to plan for, fund, and implement flood-resilient solutions.
Brian Watts is a principal associate and Forbes Tompkins is a senior manager with The Pew Charitable Trusts’ flood-prepared communities project.