Coastal Inundation
America’s coastal communities, ecosystems, and infrastructure—and the economies they support—face increasing hazards from sea level rise.
The impacts of climate change are challenging—and in some cases, devastating—coastal communities, infrastructure, and the resources our economy depends on. Many communities along the coast are already experiencing the daily realities of more frequent and severe coastal inundation events and sea level rise. The effects of coastal inundation are threatening the natural and built environment, requiring strategic investments in planning and adaptation measures that account for changing future conditions.
Sea level along the U.S. coastline is projected to rise, on average, 10 - 12 inches (0.25 - 0.30 meters) in the next 30 years (2020 - 2050)... The result will be a profound shift in coastal flooding over the next 30 years as tide and storm surge heights increase and reach further inland.
Decision-makers can find the most up-to-date sea level rise projections available for all U.S. states and territories in the 2022 Interagency Sea Level Rise Technical Report. The Interagency Sea Level Rise Scenario Tool gives users a way to explore these projections, and the Sea Level Rise Technical Report Application Guide for Decision Makers is available to assist planners in using the sea level rise data.
Maps
The federal government has extensive data resources that can be used to explore the impacts of climate change at the coast. Here's a sampling of maps and data visualizations related to sea level rise and coastal inundation.
Areas susceptible to high-tide flooding
High-tide flooding is increasingly common along U.S. coastalines as higher tides reach further inland due to sea level rise. On average, high-tide flooding occurs more than twice as often as it did just 20 years ago.
High-tide flooding is fairly shallow—averaging less than 2 feet deep—yet repeated inundation by seawater results in continual damage to streets, stormwater systems, and other underground infrastructure.
Blue shading along the coast of this map shows areas identified in State of High Tide Flooding and 2022 Outlook as most susceptible to high-tide flooding, based on their elevation and proximity to the coast.
Enter a location of interest in the search field or zoom in to a coastal area to check where high-tide flooding occurs.
Future projections
Sea level rise will bring about a profound shift in coastal inundation as high tides and storm surges will occur atop already higher water levels, reaching further inland. By 2050, “moderate” coastal inundation events—inundation to depths that typically cause some damage—are projected to occur around ten times more often than they do today, according to the 2022 Interagency Sea Level Rise Report.
This map, based on the Intermediate U.S. Sea Level Rise Scenario, shows areas projected to be below the level of average high tide for some part of nearly every day around 2050. The Intermediate U.S. Sea Level Rise Scenario is closely aligned with the current trajectory of sea level rise in most coastal regions of the United States.
Zoom in or out to see areas with blue shading.
To view projections for community-level impacts of coastal inundation or sea level rise in future decades, check Local Scenarios in the NOAA Sea Level Rise Viewer .
Intermediate-High Sea Level Rise Projections
This map displays future projections of relative sea level rise along the US coastlines under the Intermediate-High sea level scenario for 2050 and 2100. The black dots along the coastline indicate tide gauge locations used to characterize past sea level rise and project future trends.
Select the play button on the map to view the projected changes over time, zoom to local areas on the map, and click on tide gauge points to learn more about projections for that local area.
Intermediate-Low Sea Level Rise Projections
This map displays future projections of relative sea level rise along the US coastlines under the Intermediate-Low sea level scenario for 2050 and 2100. The black dots along the coastline indicate tide gauge locations used to characterize past sea level rise and project future trends.
Select the play button on the map to view the projected changes over time, zoom to local areas on the map, and click on tide gauge points to learn more about projections for that local area.
Resources to explore
Here's a selection of federal resources related to coastal resilience.