- Listen to the Diving Deeper: Tsunamis podcast to learn more about the causes of tsunamis and how to prepare for them.
- Visit the Glossary to view the definition of inundation terms commonly used throughout this website.
- Learn about the Coastal and Inland Flood Observation and Warning (CI-FLOW) project and how riverine flooding and coastal flooding events affect each other.
Understanding Coastal Inundation
The first step is to understand what inundation is and why communities should be concerned.
Inundation and Coastal Communities
What Is Inundation? Water covering normally dry land is a condition known as inundation.
Inundation events are among the more frequent, costly, and deadly coastal hazards that can impact coastal communities in the U.S. In fact, riverine and coastal inundation causes the highest number of natural-hazard-related deaths. With coastal states supporting 81% of the U.S. population and generating 83% of U.S. gross domestic product, the potential for catastrophic loss from inundation events is greater in these states than in other areas of the country.
In addition, future inundation risks may be exacerbated by local changes in climate and sea level. It is important to know current inundation risks to understand the potential effects of changing conditions.
Episodic Coastal Inundation Events
There are four primary causes of significant inundation: storm surge, tsunamis, inland flooding, and shallow coastal flooding.
Longer-Term Coastal Inundation
Sea level rise is an increase in the mean level of the ocean. NOAA has been measuring mean sea level for over 150 years, with tide stations operating on all U.S. coasts.
View works cited and additional resources for understanding inundation.