Tsunamis are a series of waves (not just one big one), most often generated by a major earthquake beneath the ocean floor. The time between crests can range from minutes to hours, and in height from a few centimetres to several metres. In the deep ocean, the waves travel about 800 kilometres per hour, but start to slow in shallower, coastal waters where their heights increase dramatically.

Tsunami Preparedness

If you live in coastal British Columbia, know your tsunami notification zone (PDF, 6.6MB), then get prepared to manage on your own for a minimum of 72 hours. Start by developing a household plan, putting together your emergency kit and connecting with your neighbours.

What To Do if There is a Tsunami Threat

Earthquakes are often a precursor to a tsunami. If you feel strong shaking, drop, cover and hold on. Then move to higher ground or, in some communities, a pre-identified safe area.

Tsunami waves can last several hours, so stay there until you receive the “All Clear” message from your local government before assuming the event is over. Never go to the beach to watch the waves. A tsunami can move faster than you can run.

How Will I Know if a Tsunami is Coming?

B.C. receives notification of a potential distant tsunami from the U.S. National Tsunami Warning Center. All information is then assessed by federal and provincial emergency officials and technical staff to determine if there is a threat to coastal BC.

If a tsunami threat is identified, Emergency Management BC will activate the Provincial Emergency Notification System (PENS), which notifies local communities and agencies with information on alert levels for the province’s five tsunami zones. Each zone includes all islands and inlets within it. What zone are you in? Emergency response plans are implemented at the local level as required.

You can also subscribe to Twitter, text and email notifications via the Intergovernmental Oceanographic Commission, US National Tsunami Warning Center (@NWS_NTWC) and Emergency Info BC (@EmergencyInfoBC).

Throughout the event, official tsunami emergency warnings and information will be broadcast by radio, television, telephone, text message, door-to-door contact, social media, weather radios and/or outdoor sirens. Always follow instructions from local emergency officials.

Types of Tsunami Alerts

Types of Tsunami Alerts










One Source, One Stop


B.C.'s central resource for emergency preparedness information.

Mark your calendar

Tsunami Preparedness Week

In British Columbia, Tsunami Preparedness Week is recognized the second full week of every April. Hosting a High Ground Hike in your coastal community is a fun and engaging way to educate residents and visitors about local tsunami risk and proper response. Learn more here.

Know Your Zone

Tsunami Notification Zones

B.C.'s coastal communities have been divided into five "notification zones" (PDF, 6.57MB). What zone are you in?

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