Updated: October 6, 2022
Ten years ago on March 11, 2011, at 2:46 p.m. Japan local time, a 9.0 magnitude earthquake occurred off the northeastern coast of Honshu, Japan, that generated a devastating tsunami.
Total damage was estimated at $220 billion, making it the most expensive disaster in history. It was the largest magnitude earthquake ever in Japan and is the fourth largest in the world since 1900.
In many coastal towns, waves flooded to at least the third or fourth floor of buildings. An estimated 500,000 houses were completely or partial destroyed, and about 500,000 people displaced. More than 18,000 individuals lost their lives – nearly all from the relentless tsunami waves.
The situation started with a large scale earthquake, followed by a deadly tsunami, and escalated with a surge in radiation levels at the Fukushima Daichi nuclear power plant.
The earthquake generated a Pacific-wide tsunami, reaching the Hawaiian Islands, and causing extensive damage to private and public property in Honolulu, Maui, and Hawaiʻi Counties.
More than 200 waves were recorded in varying heights. The counties sustained millions of dollars in damage from the event.
Then President, Obama, declared the event a Major Disaster for the State of Hawaiʻi on April 8, 2011.
Since the incident, the Hawai’i Emergency Management Agency (HI-EMA), in coordination with county partners, the University of Hawai’i system, the Federal Emergency Management Agency, and the United States Coast Guard have taken major steps to mitigate impacts to the state, enhance communications networks, improve awareness, and prepare for whenever the next tsunami may occur.
Hawaiʻi has become the first jurisdiction in the United States to implement tsunami evacuation maps for emergency response operations. The 2011 Tohoku tsunami prompted the development of extreme inundation scenarios beyond what can be inferred from historical records, and county emergency management augmented the evacuation maps with a second hazard zone delineated by modeled tsunamis from potential Mw 9.3 and 9.6 earthquakes. These can be located in the front pages of your local telephone book, as well as online.
Hawaiʻi has created the largest outdoor warning siren system in the United States. 410 sirens are installed across the islands, with 76 state-of-the-art sirens to be added, increasing coverage state-wide. The new, standardized, electronic sirens are battery powered with a photovoltaic solar charging system and have redundant cellular/satellite communications. Additionally, 73 existing legacy sirens are to be upgraded.
A wide-ranging data compendium in support of emergency management for the nine state harbors has been developed to facilitate delineation of offshore refuge areas, where vessels are evacuated to during a tsunami warning. Of equal importance to the maritime community is the occurrence of more frequent tsunami advisories, when hazardous nearshore currents are expected. The “Hawaiʻi Boater’s Hurricane and Tsunami Safety Manual” can be found online.
The HI-EMA Public Assistance Branch facilitated over $6.4 million in federal dollars for repair projects across the state resulting from the 2011 tsunami. In such time, all reparations have been completed and three projects remain to be approved and closed by FEMA.
From the newly expanded Continuity of Operations location nestled in Diamond Head Crater, seismic activity is constantly monitored with the continuous vigilance of the State Warning Point Team.
Revised and updated Tsunami Response Checklists, for Local and Distant Earthquake events that produce a tsunami, have been developed and practiced. Emergency lines of communication between SWP and the four counties’ early warning centers are routinely tested, and additional communications systems have been installed in case the primary and secondary systems are ever interrupted. Also, the agency has upgraded its FEMA authorized software for use of the Intergraded Public Alert and Warning for Emergency Alert System and Wireless Emergency Alerts notifications over TV, Cable, Radio, & WEA enabled/compatible cellular devices. The agencies internal mass notification system for situational awareness and staff recall was also upgraded.
The HI-EMA encourages every resident to take steps now to prepare for any emergency and protect your ʻohana.
Pack a 14-day ‘Go-To-Kit’ for your family
- Change of clothes and sturdy shoes
- 1 gallon of water per person per day
- Non-perishable foods
- Masks, gloves, and sanitizer
- First aid kit
- Battery powered or crank powered radio
- Manual can opener
- Hygiene supplies
- Important documents
Make a plan
- Plan escape routes – ensure all family members know where to go and how to get out
- Meeting place – choose a physical location to meet if communication between family members is down
- Family communication – identify a family member who lives out-of-state who everyone can notify when they are safe
After a strong or long earthquake, a tsunami may follow. If you feel the ground shake.
- Drop, cover and hold on
- Evacuate quickly on foot to high ground or far inland
- Wait for local officials to advise on cautionary re-entry
Sign up for Emergency Notifications
Please visit the HI-EMA website for links to each County website for free text-based notifications for the latest updates on natural disasters and man-made emergencies
We cannot go back in time and change history, nor can we control the dynamics of our planet. Yet we can and must learn from the past, prepare for whatever the future may bring, and work to limit tsunami impacts to our state and people. For more information visit ready.hawaii.gov.