Tsunamis are series of waves triggered by an earthquake, volcanic activity, or underwater landslide offshore. A tsunami can move at hundreds of miles per hour and can be 10-100 feet high. Even 10-foot tsunamis can be very destructive. Areas near the coast, within a mile of the shoreline, and that are less than 25 feet above sea level are at the most risk for a tsunami.
How to Prepare For a Tsunami
- Be informed and know tsunami terminology:
- Warning—A tsunami with the potential to generate widespread inundation is imminent or expected. People in the warned area are encouraged and may be ordered to evacuate.
- Advisory—A tsunami with the potential to generate strong currents or waves dangerous to those in or very near the water may be imminent or expected, but significant inundation is not expected for areas under an advisory. Beaches, harbors, and marinas in the warned area may be closed.
- Watch—An earthquake that could produce a tsunami has been detected.
- Information Statement—In most cases indicates that an earthquake has occurred or a warning, watch, or advisory has been issued for another section of the ocean with no imminent threat to the local area to prevent unnecessary evacuations.
- Determine whether you live or work in an area with the potential to be hit by a tsunami.
- Determine where tsunami signs are located.
- Whether you live in the area or are a tourist, know the community’s warning systems and evacuation protocols.
- Make a written family evacuation plan. Identify a place to evacuate that is at least 100 feet above sea level or two miles inland and you can reach within 15 minutes.
- Make a written emergency communication plan in case family members are separated.
- Build an emergency kit.
What to Do If There Is a Tsunami
- Stay tuned to the radio or TV for more information or instructions. Authorities will issue a warning only if they are certain a threat exists.
- Stay away from the beach.
- A large recession of the water is nature’s warning of a tsunami. Heed this as you would an official warning.
- There may be little time between a warning and the tsunami, so if you are told to evacuate, do so immediately, and take your animals with you.
- If you hear an official tsunami warning or are told to evacuate:
- Immediately get to higher ground, preferably a previously identified area.
- Take your emergency kit.
- Once you are in a safe place, muster with your command if you are military or civilian personnel or a member of the selective reserves.
What to Do After a Tsunami
- Continue to listen to news reports for further information and instructions.
- Stay clear of flood waters (standing and moving) as they may be contaminated or deeper than expected.
- Stay clear of damaged areas until you are told otherwise.
- Beware of downed power lines.
- Return home only after local officials tell you it is safe.
- Avoid any roads where waters have receded as they may have weakened and could collapse under the weight of a car.
- Be extremely cautious when entering buildings and homes as there may be unseen damage.
- Clean and disinfect everything that was touched by flood water, as it can contain sewage and other contaminants.
- After a declared emergency, register your needs with the Navy through the Navy Family Accountability and Assessment System (NFAAS) at https://navyfamily.navy.mil or call 1-877-414-5358 or 1-866-297-1971 (TDD).
Where to Find Additional Information
- Centers for Disease Control and Prevention (CDC)—www.bt.cdc.gov/disasters/tsunamis/
- Department of Homeland Security (Ready.gov) & FEMA—www.ready.gov/tsunamis