A new report from the Government Accountability Office (GAO) says the U.S. Coast Guard is not sufficiently prepared to deal with tsunamis.
The Pacific Northwest is home to seismic hazards, including the Cascadia Subduction Zone (CSZ). This is a large fault 50-100 miles offshore known to produce large earthquakes and tsunamis that may necessitate the evacuation of Coast Guard personnel and dependents during a major event.
GAO’s review found however that only 19 of the 39 Coast Guard units at risk in this region have a written tsunami evacuation plan for personnel and their dependents. The plans varied significantly and many of those that did have plans had not exercised them.
The CSZ is approximately 800-miles long and is located 50 to 80 miles off the coasts of Washington, Oregon, Northern California; and British Columbia, Canada. According to the Federal Emergency Management Agency (FEMA), such subduction zones produce some of the world’s largest earthquakes, which can exceed magnitude 9.0, generate large tsunamis, and produce aftershocks for months afterwards. FEMA says a full rupture of the CSZ fault may generate ground shaking up to five minutes and an initial tsunami wave of between three and 80 feet reaching the outer coast of Washington and Oregon within 10 to 30 minutes. Tsunami arrival estimates along Washington’s inner coast may exceed one hour from rupture. According to the Oregon Office of Emergency Management, scientists estimate there is a 37 percent chance that a magnitude 7.1 or greater CSZ event will occur in the Pacific Northwest within the next fifty years.
Seismic activity is difficult to predict and the CSZ fault could generate a major earthquake and tsunami without warning that would affect millions of people’s lives, property, infrastructure, and the environment for years. FEMA planning documents state that approximately 86,000 people in the Pacific Northwest live in the CSZ tsunami inundation zone. A full rupture of the CSZ fault could injure over 107,000 people, result in nearly 14,000 deaths, and severely damage approximately 620,000 buildings, 2,000 schools, 100 hospitals, and all seaports on the Pacific Northwest coast.
GAO is understandably concerned about Coast Guard’s lack of evacuation plans, given the potential scale of such a disaster in the Pacific Northwest (District 13). The watchdog found not only a lack of evacuation plans but a lack of leadership on the issue, noting that “Coast Guard does not ensure units in this seismically active region of the United States create tsunami evacuation plans”. Instead, each unit’s leadership determines whether to develop a plan.
Of the 19 plans that did exist at the time of GAO’s review, the watchdog found much variation, due primarily to lack of guidance. For example, seven plans direct personnel to evacuate upon detecting major seismic activity, whereas the remaining 12 direct personnel to wait for an official tsunami warning before initiating evacuation procedures. National Oceanic and Atmospheric Administration (NOAA) officials responsible for operating the National Tsunami Warning System told GAO that evacuation procedures should begin upon detecting a major earthquake. Specifically, NOAA officials explained that damage to communication infrastructure caused by the initial earthquake may inhibit units from receiving an official warning and any delay in evacuating the tsunami inundation zone may result in the loss of life.
While Coast Guard provides units with contingency planning templates that include explicit procedures for emergency evacuation for various natural hazards, including earthquakes, hurricanes, and wildfires, it has not done so for tsunamis.
Leadership at the units GAO visited that had written tsunami evacuation plans did not know the feasibility of their plans because they had not exercised them due, in part, to the impact of COVID-19 on in-person gatherings. GAO’s report states that “Coast Guard officials were unaware of past attempts to exercise their unit’s plan or the frequency, results, and lessons learned from exercises”.
While GAO’s report exposes shortfalls in Coast Guard’s tsunami evacuation planning, it is not without recognition for the work already undertaken by the agency and welcomed its work on tsunami preparedness including contingency plans, emergency communications equipment purchases, and participating in emergency response exercises. Some key steps the Coast Guard has taken include District 13’s development of the All-Hazards plan, which includes protocols for responding to a variety of natural hazards, including a CSZ event. In addition, following Coast Guard’s involvement in Cascadia Rising 2016, a national level exercise, involving federal, state, and local emergency management officials, it developed and submitted after-action reports documenting lessons learned, best practices, and recommendations for improvement.
To address the shortcomings discovered in its review, GAO has made three recommendations to the Commandant of the Coast Guard:
- Ensure that coastal units in the Pacific Northwest develop location-specific evacuation plans.
- Ensure that coastal units in the Pacific Northwest are provided with tsunami evacuation planning guidance that includes protocols for personnel and dependents.
- Ensure that coastal units in the Pacific Northwest assess the feasibility of their tsunami evacuation plans through regular exercises that provide participation opportunities for Coast Guard personnel and dependents.
The Department of Homeland Security concurred. However, GAO is concerned at the timeliness of Coast Guard’s response to the recommendations. The agency does not anticipate developing written tsunami evacuation plans and providing guidance to units for plan development until December 31, 2025. It also does not anticipate that units will exercise their plans until December 31, 2026.