U.S. Tsunami Preparedness:

Federal and State Partners Collaborate to Help Communities Reduce Potential Impacts, but Significant Challenges Remain

GAO-06-519: Published: Jun 5, 2006. Publicly Released: Jun 5, 2006.

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The 2004 Indian Ocean tsunami raised questions about U.S. preparedness for such an event. The National Oceanic and Atmospheric Administration (NOAA) leads U.S. detection and warning efforts and partners with federal and state agencies in the National Tsunami Hazard Mitigation Program (NTHMP) to reduce tsunami risks. In 2005, Congress appropriated $17.24 million in supplemental funding to enhance these efforts. This report (1) identifies U.S. coastal areas facing the greatest tsunami hazard and the extent to which potential impacts have been assessed, (2) discusses the effectiveness of the existing federal tsunami warning system, (3) describes efforts to mitigate the potential impacts of tsunamis on coastal communities, and (4) assesses NOAA's efforts to develop long-range plans for federal tsunami programs.

NOAA has determined that the Pacific coast states of Alaska, California, Hawaii, Oregon and Washington, as well as Puerto Rico and the U.S. Virgin Islands in the Caribbean Sea, face the greatest tsunami hazard. The east and Gulf coasts are relatively low-hazard areas. While high-hazard areas have been identified, limited information exists on the likely impacts of a tsunami in those areas. Some coastal areas lack inundation maps showing the potential extent of tsunami flooding in communities, and others have maps that may be unreliable. State assessments of likely tsunami impacts on people and infrastructure have been limited, in part, due to a lack of tsunami loss estimation software, as exists for floods and other hazards. Although federal warning centers quickly detect potential tsunamis and issue warnings, false alarms and warning system limitations hamper their effectiveness. Some state and local emergency managers have raised concerns about false alarms--the 16 warnings issued since 1982 were not followed by destructive tsunamis on U.S. shores--potentially causing citizens to ignore future warnings. Furthermore, limitations in the Emergency Alert System and NOAA Weather Radio All Hazards may impede timely warnings to communities. For example, signal coverage for these two systems is insufficient to transmit warnings to some coastal areas and failure to properly activate them has resulted in warnings being delayed or not transmitted to some locations. NOAA has begun addressing false alarms but, according to agency officials, lacking the states' permission elsewhere, has only conducted "live" end-to-end testing of the warning systems in Alaska to identify problems. The at-risk communities GAO visited have mitigated potential tsunami impacts through planning, warning system improvements, public education, and infrastructure protection, but the level of implementation varies considerably by location. Most of the states and some communities GAO visited have basic mitigation plans identifying tsunami hazards. While all of these locations have multiple warning mechanisms in place, disruptions to key infrastructure such as telephone lines may hamper timely warnings. Furthermore, key educational efforts, such as distributing evacuation maps and developing school curricula have not been consistently implemented. In addition, few states and communities protect critical infrastructure from tsunamis through land-use and building design restrictions. Emergency managers attributed variability in their efforts to the need to focus on more frequent hazards like wildfires and to funding limitations. Furthermore, few communities participate in NOAA's preparedness program, according to NOAA officials, because they perceive the threat of a tsunami to be low. The nationwide expansion of NOAA's tsunami-related activities and NTHMP is under way; however, the future direction of these efforts is uncertain because they lack long-range strategic plans. NOAA has yet to identify long-range goals, establish risk-based priorities, and define performance measures to assess whether its tsunami-related efforts are achieving the desired results.

Recommendations for Executive Action

  1. Status: Closed - Implemented

    Comments: In a September 2006 meeting of the White House Subcommittee on Disaster Reduction, NOAA officials initiated coordination with officials from the Federal Emergency Management Agency (FEMA) and the United States Geological Survey (USGS) for the development of a tsunami module to add to FEMA's existing hazard loss estimation software, and also discussed the need for FEMA to receive additional funding for its completion. NOAA will continue to support the development of a tsunami module for FEMA's loss estimation software and other tsunami mitigation products and decision tools.

    Recommendation: To help improve national tsunami preparedness, the Secretary of Commerce should direct the NOAA Administrator to work with the Federal Emergency Management Agency Director and the U.S. Geological Survey Director to create standardized tsunami loss estimation software to help communities determine the potential impact of tsunamis and identify appropriate mitigation actions.

    Agency Affected: Department of Commerce

  2. Status: Closed - Implemented

    Comments: This recommendation consisted of four sub-parts. NOAA has addressed each of them. First, NOAA completed the planned expansion of its deep-ocean tsunami detection stations (known as DART buoys) in March 2008. Second, NOAA conducted a review of the criteria it uses to determine when alerts are issued and to which area, which was published in the Science of Tsunami Hazards Journal in May 2008. Third, in 2006, NOAA expanded the scope of the National Tsunami Hazard Mitigation Program Warning Coordination Subcommittee to include state and federal scientific experts, and uses this as a venue to review warning guidance procedures as requested by the subcommittee members. Fourth, the NOAA Tsunami Program produced a strategic plan, which contains, among other things, performance measures for assessing the timeliness and accuracy of tsunami forecast and warning products that will guide improvements over the next 5 years.

    Recommendation: To help improve national tsunami preparedness, the Secretary of Commerce should direct the NOAA Administrator to reduce the number of tsunami warning false alarms by (1) completing the planned expansion of tsunami detection stations, (2) reexamining the National Weather Service's rules dictating when a warning will be issued and to which areas, (3) establishing a routine process for other federal and state experts to formally review and comment on the centers' use of seismic data, and (4) setting performance goals to guide improvements.

    Agency Affected: Department of Commerce

  3. Status: Closed - Implemented

    Comments: NOAA officials have met with the National Tsunami Hazard Mitigation Program (NTHMP), which includes state emergency managers, to discuss end-to-end testing of the tsunami warning system. With NOAA's support, the NTHMP agreed to encourage states to participate in end-to-end testing and to make the topic an agenda item for future NTHMP annual meetings. Furthermore, NOAA has directly contacted the states of California, Oregon, and Washington to encourage end-to-end testing. As a result, on June 20, 2007, NOAA met with the California Governor's Office of Emergency Services to develop a strategy for a joint end-to-end tsunami communications exercise in California with the state of Alaska planned for March 2008.

    Recommendation: To help improve national tsunami preparedness, the Secretary of Commerce should direct the NOAA Administrator to work with the states to conduct periodic end-to-end tests of the tsunami warning system, including NOAA Weather Radio and the Emergency Alert System, to ensure the system will function as intended during a tsunami emergency.

    Agency Affected: Department of Commerce

  4. Status: Closed - Not Implemented

    Comments: In April 2010 we issued another report on the status of U.S. tsunami preparedness. During the fieldwork we followed-up with NOAA on the status of this recommendation. As we found out and later reported in GAO-10-490, NOAA has not conducted a formal assessment to identify barriers to or possible incentives for participating in the TsunamiReady program as we recommend in 2006. As such, this recommendation will be closed as not implemented.

    Recommendation: To help improve national tsunami preparedness, the Secretary of Commerce should direct the NOAA Administrator to evaluate the TsunamiReady program to determine what barriers, if any, exist to participation and what modifications are needed to encourage more high-risk communities to participate.

    Agency Affected: Department of Commerce

  5. Status: Closed - Implemented

    Comments: From May 15-17, 2007, NOAA hosted an external assessment of the NTHMP in Seattle, Washington. The review addressed past goal attainment, impacts of the Tsunami Warning and Education Act (PL 109-424), and provided recommendations for program improvements. Information on the assessment including individual assessments by the five external review panel members can be retrieved from the NTHMP's website: http://nthmp.tsunami.gov/assessments.html

    Recommendation: To help improve national tsunami preparedness, the Secretary of Commerce should direct the NOAA Administrator to evaluate the NTHMP to determine what has worked well in the past and what high priority activities remain to be completed and to help inform strategic planning efforts.

    Agency Affected: Department of Commerce

  6. Status: Closed - Implemented

    Comments: NOAA issued its Tsunami Program Strategic Plan for 2008-2017 on 7/31/08 and the National Tsunami Hazard Mitigation Program completed its strategic plan on 11/20/08.

    Recommendation: To help improve national tsunami preparedness, the Secretary of Commerce should direct the NOAA Administrator to develop comprehensive risk-based strategic plans for the Tsunami Program and National Tsunami Hazard Mitigation Program that consider input from states and federal partners and include metrics for measuring progress toward achieving program goals.

    Agency Affected: Department of Commerce


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