How do I know if my Flood Factor score is accurate?

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First Street Foundation’s Flood Model was scrutinized by a panel of experts who found the methods used to determine Flood Factors accurate and of high quality.

The data used to determine a property's Flood Factor® comes from the First Street Foundation Flood Model, which is based on decades of peer-reviewed research and developed in collaboration with more than 80 world-renowned experts. The Flood Model's methodology was reviewed by experts in the field, who confirmed its scientific rigor and deemed it worthy of scientific publication.

Flood Factor simplifies flooding so every American can determine their risk, understand the science, and make informed decisions to prepare for the future.

The First Street Foundation Flood Model 

The First Street Foundation Flood Model is a nationwide, probabilistic flood model that integrates all major flood types, from tides, coastal surges, rains, and rivers and uses historical flooding events to validate risk. The data the model produces undergo multiple reviews and must pass comprehensive checkpoints before being made publicly available.

  • Where possible, data has been validated against historic flood reports and government flood claims.
  • In developing its flood model, First Street Foundation created the first national adaptation database, including more than 40 different adaptation types, which is used to both inform and validate flood projections.
  • All methods used by the First Street Foundation Flood Model have undergone an expert academic panel review and have been submitted to scientific peer-review journals.

But my property has never flooded nor is it in a FEMA SFHA 

Your FEMA zone and Flood Factor are two independent risk assessments. The main difference between the two is that Flood Factor considers the impact of climate change and the risk of flooding from rain. FEMA flood maps identify over 1.1 million miles of flood hazard areas, while Flood Factor’s national flood model shows that flood risk is more widespread, with over 24 million properties in the U.S. at risk over the next 30 years.

As sea levels continue to rise, sea surface temperatures continue to increase, and the atmosphere continues to warm, floods will increase in both frequency and severity. A warming atmosphere means more evaporation and more water is available for rain, which contributes to changing weather patterns and flood risks. Extreme rain events are increasing in duration, intensity, and frequency, which causes more urban and flash floods, and more flooding from overflowing rivers and streams.

The importance of Flood Factor

Without free access to accurate flood information, more Americans will unknowingly be at risk from the nation’s costliest natural disaster. Flood Factor was created to quantify and communicate America’s flood risk. By making flood risk data freely available for all, individuals and communities can prepare for and mitigate risks before they become a reality. 

First Street Foundation® supports scientific collaboration and data transparency and created Risk Factor to make its peer-reviewed research on these risks freely available to all. Presented with easy-to-understand graphs and text to ensure every American has “access” peer-reviewed climate change research in a way that is understandable. Search your home state, county, city, or zip code on to understand if you may be threatened by climate-intensified flooding. 

Like all flood models, it's intended to help identify potential flood risks, and Risk Factor users are encouraged to follow up with qualified professionals and supplement this information with additional research and documentation they might have.

Press Coverage

The New York Times: New Data Reveals Hidden Flood Risk Across America

The Washington Post: Millions of homeowners face flood risks without realizing it, and climate change is making it worse

CNN: Flood risk is growing for US homeowners due to climate change. Current insurance rates greatly underestimate the threat, a new report finds

The New York Times: Climate Threats Could Mean Big Jumps in Insurance Costs This Year

Bloomberg: Most Americans Don’t Have Enough Flood Insurance for Climate Change

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