The flood risk landscape has dramatically worsened since 2020. Hurricane Helene, which sent floods tearing through the Southeast, headlined 27 disasters in the United States in 2024 that individually cost $1 billion or more. It was the second-highest number since the NOAA record began in 1980. Meanwhile, 2023 saw 28 weather and climate disasters, surpassing the previous record of 22 in 2020, reaching a price tag of at least $92.9 billion. Knowing your home’s risk could save your life and could save you money.
The Earth’s rapidly changing weather patterns make historic flood risk projections increasingly unreliable. Research from the New York-based nonprofit First Street Foundation launched in 2020 on the finding that 67% more American homes than previously estimated face high flood risk during the next 30 years. Recent updates show the situation has only intensified.
A February 2025 study published in Nature Communications found that by 2100, flood exposure could rise, threatening 1.9 billion people globally. Human migration will account for 77% of the increased risk, while climate change will drive 21% of the threat. Low-income and urban regions will be most affected. According to First Street Foundation’s ongoing analysis, 14.6 million properties face substantial flood risk—nearly 70% more than FEMA’s 8.7 million properties classified as high-risk. Almost six million U.S. households and property owners currently underestimate or remain unaware of their flood risk.
The First Street Foundation’s flood assessment goes beyond traditional approaches by incorporating sea-level rise and extreme weather projections. When these factors are included, many more homes—not just in low-lying coastal areas but also in desert communities like Phoenix, Arizona, and mountainous regions—face significant flood risk.
Take a moment to understand your flood risk now to improve your preparations and protect your investment.
Why Has the Risk Profile Changed So Dramatically?
U.S. flood risk analysis has traditionally relied on historical data, but climate change is supercharging the increasing frequency and intensity of extreme weather that lead to billion-dollar disasters.
Consider Houston’s experience of three “500-year storms” within just three years. Based on traditional modeling, the record-breaking floods should never have happened in such a short time. Likewise, 2024 saw unprecedented global flooding, impacting regions across Central Asia, East Africa, West Africa, Southeast Asia, and Central Europe.
Flooding is becoming more frequent along U.S. coasts, as most sites measured have experienced an increase in coastal flooding since the 1950s. Even more concerning, the nation is predicted to experience four to eight high tide flooding days during 2025, an increase of five more flood days per year since 2000.
One of the most critical updates to understand is that low-lying coastal land is not the only geography at extreme flood risk. Research since 2020 has revealed that flood danger extends far beyond traditional flood zones.
Mountainous and Steep Terrain
Mountains and steep hills produce rapid runoff, which can cause streams to rise quickly. A creek only 6 inches deep in mountainous areas can swell to a 10-foot deep raging river in less than one hour if a thunderstorm drenches an area for an extended period. The photo below of Elk Creek in Southern Oregon, which passes behind Earth911’s home base, shows how a creek that is six inches deep during the summer can become a torrential flood when heavy rains fall.
Steep terrain, torrential wintertime storms, and wildfires combine to put the Santa Barbara coastal watershed at high risk of flash flooding and mudslides, as rainfall screams down canyons carved into the Santa Ynez Mountains. Colorado reports approximately 30-40 flash flood warnings annually, with the highest concentration of warnings occurring in mountainous regions.
Urban Areas
Densely populated areas are at a high risk of flash floods. The construction of buildings, highways, driveways, and parking lots increases runoff by reducing the amount of rain absorbed by the ground. New York City alone experiences more than 50 flash flood warnings each year, mainly due to the combined effect of urbanization and intense summer storms.
Desert and Arid Regions
In deserts, flash floods can be particularly deadly, as the recent flooding that killed at least 135 people demonstrated, for several reasons. First, storms in arid regions are infrequent. Yet, they can deliver an enormous amount of water in a very short time. Second, these rains often fall on poorly absorbent and often clay-like soil, which significantly increases the amount of runoff.
First Street found increased flood risk in Idaho, Utah, and Arizona, regions not traditionally considered flood-prone. As heavy rainfall events become more intense and frequent, flash and river flooding affect areas previously thought safe.
Multiple resources now exist to help you assess your property’s flood risk.
Essential Assessment Tools
FloodFactor.com. First Street Foundation’s free tool remains available and continues to be updated, but detailed reports require a subscription. The platform provides physically-based flood model forecasts showing how climate change will impact flood risk from rain, streamflow, sea level rise, and storm surge. Enter your address to get a comprehensive risk assessment.
ClimateCheck. Free climate risk reports are available for virtually all U.S. addresses. The site requests an email address before sending a report.
FEMA’s Flood Map Service Center. The official source for National Flood Insurance Program flood hazard information, providing flood hazard and risk data products to help communicate flood risk and inform mitigation actions.
FEMA’s National Risk Index. An easy-to-use, interactive tool that shows which communities are most at risk from 18 natural hazards.
Other Specialized Tools
Climate Central’s Surging Seas Risk Zone Map, including the Coastal Risk Finder tool released in 2025, provides detailed coastal flood risk analysis.
Federal Resources
State-Level Tools
Many states now offer flood risk assessment tools, such as Pennsylvania’s Flood Risk Assessment Tool, which provides access to available flood data from FEMA and other sources about locations in the state.
Immediate Assessment
Use FloodFactor.com, ClimateCheck, and FEMA’s tools whenever you’re shopping for a new home or evaluating your current property. The past flood history of a property is crucial to understanding its future flood risk, but it’s hard to find out if a particular property has filed previous flood insurance claims with the National Flood Insurance Program because of privacy concerns.
Property Protection Strategies
The risk isn’t just theoretical; it directly affects property values. Imagine trying to sell a home when the flood risk has increased significantly since it was purchased. The reality of flood risk has sunk in, the evidence can be seen as more than 3.2 million Americans have left high flood risk neighborhoods. These migrations create “climate abandonment areas” that are expected to decline in population by an additional 16%—some 2.5 million people—who will flee due to flood risk over the next 30 years, according to PreventionWeb.
Once you have a sense of your flood risk, consider specific flood mitigation measures:
- Move downspout outlets further from your home to avoid flooding of your foundation, even if rising water doesn’t reach the house.
- Landscape to direct water away from your foundation and into drainage rather than areas where it can accumulate.
- Ensure gutters are clear and don’t pour water under the eaves, which can rot, or into the house.
- Consider placing flood barriers, such as sandbags or berms, for areas prone to even minor flooding.
For detailed flood preparation guidance, visit State Farm’s flood preparation resources and FEMA’s Risk MAP program.
Insurance Considerations
Review your home insurance carefully to ensure adequate flood coverage. Visit FloodSmart.gov to learn about flood insurance options. Standard homeowner’s insurance typically doesn’t cover flood damage. Even if you’re not in a designated flood zone, flood insurance may be critical. Nearly 6 million households and property owners have underestimated or been unaware of their current risk because they were not identified as being within FEMA’s Special Flood Hazard Area zones.
Stay Informed About Changing Conditions
Human-caused climate change is increasing the frequency and intensity of extreme weather. Monitor local weather alerts and understand that flood risk can change rapidly. Post-Wildfire Conditions: Wildfires strip away vegetation that would typically help absorb water, so that rainwater runs off quickly, causing debris flows and flash flooding.
It’s On All Of Us Now
Flood risk in America has increased dramatically since 2020, with record-breaking disaster frequency and costs. But recent federal changes suggest that the government is stepping away from its role as the backstop during disasters. The geography of risk extends far beyond traditional coastal flood zones to include mountainous areas, urban centers, and even desert regions. With many free tools now available to assess your specific property risk, we can be better prepared to avoid and respond to flood risk.
Whether you’re a current homeowner or shopping for property, understanding your flood risk is now essential for both safety and financial protection. Take advantage of these resources today. Your life and savings may depend on it.
Editor’s Note: This article first appeared on July 8, 2020, and was substantially updated in August 2025.
