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Tsunamis

Tsunamis are large, deadly ocean waves that are generated from an earthquake or other disturbance (such as volcanos or landslides). These events can be scary, dangerous, and deadly if we are not prepared; if you are caught in a tsunami the survival rate is very low.  Below is a short, helpful guide on what to do before, during, and after a tsunami.   

This tsunami model illustrates the impact a tsunami would have on Bali, Indonesia.  Notice the time series graphs that show how long a tsunami lasts and how many waves are involved.

Before a Tsunami

Many things can be done to protect yourself and your family from the dangers of tsunamis, yet few people take these three necessary precautions.

BAT

1. Practice the 20-20-20 Rule

The 20-20-20 principle is simple.  If the ground shakes for greater than 20 seconds, you have 20 minutes to evacuate to a location at least 20 meters higher in elevation.  Practicing this principle with your family, friends, and neighbors before a tsunami hits allows you to have confidence in your evacuation route before you are in danger.

Ground shakes for > 20 seconds

20 minutes to evacuate

Get to a location at least 20m higher in elevation

DAT

During a Tsunami

1. Don't wait for a warning form local or government leaders!

The earthquake itself is a warning.  If the ground shakes for more than 20 seconds, even if the shaking is weak, evacuate immediately. Do not delay by trying to find family and friends.

2. Remember 20-20-20!

Remember the 20-20-20 principle you practiced!  If the ground shakes for greater than 20 seconds, you have 20 minutes to evacuate to a location at least 20 meters higher in elevation.  Following this principle has kept many individuals, families, and communities safe in the face of dangerous "killer waves."

Ground shakes for > 20 seconds

20 minutes to evacuate

Get to a location at least 20m higher in elevation

AAT

After a Tsunami

Wait before you go back to the coast

Don't return to the coast to look for survivors immediately after the first wave.  Oftentimes, the second, third, and fourth waves can be more dangerous than the first.  Listen to local officials and emergency management services for information on when it is safe to return to the coast.

OR

Other Resources

View these resources for more information on how to keep you and your family safe in the event of a tsunami.

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