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About the National Tsunami Hazard Mitigation Program (NTHMP)


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NTHMP Vision: Reduced loss of life and property when a tsunami strikes any U.S. state or territory and resilient communities that are prepared for tsunami hazards

As demonstrated by the 2004 Indian Ocean and 2011 Japan events, tsunamis can be devastating. In the United States, history and geologic evidence show that tsunamis are a significant threat. Since the beginning of the 20th century, 36 tsunami events have caused more than 500 deaths and over $1.9 billion (2017 dollars) in damage to U.S. coastal states and territories. Recent studies indicate that in the future, a large U.S. tsunami could affect millions of people and cause tens of billions of dollars in damage. Tsunamis cannot be prevented, but their impacts on life, property, and the economy can be greatly reduced.

In 1995, recognizing the threat, the U.S. Congress directed the National Oceanic and Atmospheric Administration (NOAA) to form and lead a federal/state working group to develop a plan for reducing tsunami risk to U.S. coastal communities. This group formed what has become a model for federal/state partnerships—the National Tsunami Hazard Mitigation Program (NTHMP). Following the 2004 Indian Ocean tsunami, Congress passed the Tsunami Warning and Education Act to strengthen the capabilities of this partnership "to improve tsunami preparedness of at-risk areas in the United States and its territories." An update to this act—the Tsunami Warning, Education, and Research Act—was signed into law in 2017.

Today's NTHMP includes NOAA, the Federal Emergency Management Agency, the U.S. Geological Survey, and 28 U.S. states and territories (states). This strong and active partnership connects states with the federal agencies responsible for the U.S. Tsunami Warning System and brings together the expertise and experiences of all the partners. This enables all levels of government to work together toward the common goals of protecting lives and reducing economic losses from tsunamis at the community level.

Reducing the Impacts of Tsunamis


Through collaboration, coordination, and financial and technical support to partner states, the NTHMP works to reduce the impact of tsunamis on the nation. NTHMP activities affect, either directly or indirectly, everyone in the United States, including coastal residents and visitors, emergency managers, land-use planners, elected officials, educators, government and business organizations, the military, and the tourism and maritime industries.Tsunami Sign

The NTHMP is led by a Coordinating Committee made up of representatives from its partner organizations. This committee guides the work of subcommittees established to address three key functions of the NTHMP: hazard assessment, warning guidance, and mitigation (sustained action to reduce or eliminate the long-term risk to human life and property). To support, supplement, and implement the work of these subcommittees, Congress authorized NOAA to provide financial assistance to NTHMP partner states for tsunami-related activities.