Tsunamis – Get prepared

Tsunamis move rapidly through deep water (up to 800 km/h) until they surge or break onshore causing damage by impact, floods, and washing debris back into the body of water.

When they reach shore, tsunamis may appear as rapidly rising or falling tides, a series of breaking waves, or a wave that is shaped like steps with a steep front. A tsunami can happen at any time of year even if there is ice. If you live in a tsunami zone, take steps to prepare.

How to prepare before a tsunamis

Whether you live by the ocean or are just visiting, it is important that you know the risks and take steps to prepare for tsunamis.

• Make a household emergency plan. Consider the specific needs of all members of your household, including older adults, children, pets, and anyone with special health needs
• Prepare your emergency kit. Learn more about what items to put in your kit, including quick and easy steps you can take right away
• Learn about tsunami alert types and the difference between a watch, warning, and advisory
• In some cases, you may not receive an alert before a tsunami. It's important to know the environmental signs:
  • Feeling strong earthquake for 20 seconds or more near the coast
  • Noticeable rapid rise or fall of coastal waters
  • Coastal water making unusual noise sounding like an approaching train, plane, or whistling
• Stay connected to a weather and tsunami alerting service to receive the latest weather information

Plan to evacuate

• Check with your local government for maps, evacuation routes and safe areas
• Plan to go as far inland and as high up as possible
• Plan an evacuation route that follows official guidance, when available
• You should be able to reach your safe location on foot within 15 minutes
• Know your local safe zones and evacuation routes and how to get there by on foot, by bike, or by car
• Roads may be blocked and driving may be difficult. Plan multiple evacuation routes using different transportation methods
• Practice your evacuation routes during the day and night, once a year
• Find out if your home, school, workplace or other frequently visited locations are in tsunami risk areas
• For high risk areas, create an evacuation plan with all household members:
  • Keep essential needs in mind, such as medical and mobility needs
  • Be ready to evacuate at a moment's notice
  • If your children are in school or daycare, know their evacuation route and planned safe area

Tsunami alerting in Canada

Successful tsunami alerting is based on detection of distant undersea earthquakes. However, alerting for some tsunamis is challenging. Tsunamis that are caused by landslides, volcanic activity and air pressure disturbances are difficult to detect. When a tsunami starts close to the coast, there may not be enough time for an alert to reach the affected population before the tsunami arrives. Because of these challenges, it is important to be aware of tsunami alert types as well as natural tsunami warning signs, and that you are ready to react on short notice.

When they are available, tsunami watches, warnings and advisories may be issued by Environment and Climate Change Canada in partnership with provincial and federal organizations in response to a message from the United States’ National Tsunami Warning Center. Alerts may be updated over the course of several hours. You should monitor official channels until a tsunami alert is officially cancelled.

Where to get information

• Stay connected to weather alert services that share weather warnings, watches, advisories and statements:
  • WeatherCAN app provides local weather alert notifications
  • Weather information including public weather alerts across Canada
  • Weatheradio network hosts a listing of radio weather broadcast frequencies by province or territory
  • Hello Weather provides forecasts, conditions, and other weather information by telephone
  • Local radio and television broadcasts will help you stay up to date with the latest local weather information
• The Canadian Coast Guard's Marine Communications and Traffic Services broadcasts tsunami alerts to mariners
• Some local authorities also have tsunami warning sirens. Contact your local government to find out more
• The United States' (US) National Tsunami Warning Center (NTWC) provides tsunami monitoring, detection, analyses, assessment, and messaging for the ocean coasts of Canada, the continental United States (including Alaska), the Caribbean Sea, and the Gulf of Mexico.
• Learn more about tsunami alerting in Canada, including who issues alerts and when

Prepare for safe boating

In addition to staying connected to tsunami alerting services, mariners should make additional plans to stay safe during tsunamis

• Talk to your harbour master to learn about local tsunami procedures
• Know how long it takes your boat to get to deep water, at least to a depth of the 30-fathom line (180 feet)
• Ensure your boat has enough supplies to sustain you and your crew at sea for at least 24 hours

During a Tsunami

If you receive an alert or official instructions, or if you observe warning signs of a tsunami, follow your evacuation route to higher ground immediately.

If you're in a tsunami warning area

• Evacuate inland or to higher ground, above and beyond tsunami hazard zones
• If you can't get to higher ground, stay inside where you are protected from the water
• Get to an upper floor on the landward side of the house, away from windows
• Stay alert for updated tsunami watches, warnings, and advisories
  • Updates are usually provided every 30 to 60 minutes until a warning, watch or advisory is canceled

If you observe natural warning signs of a tsunami

• If you feel a strong earthquake or extended ground rolling, move inland or uphill by foot
• If the ocean recedes to reveal seafloor, or rises higher than usual, move inland or uphill by foot
• Follow your designated tsunami evacuation route
• Do not stay and watch an incoming tsunami, as they move faster than a person can run

If you're in a tsunami advisory area

• Large waves are expected in areas under an advisory
• Follow instructions from your local emergency officials for detailed local information
• Move out of the water to avoid strong currents
• Move off the beach, and away from harbors, marinas, breakwaters, bays and inlets
• Don't go to the shore to watch a tsunami

If you're at sea during a tsunami

If you are on a boat when you receive either an official tsunami alert, or if you observe the natural warning signs of a tsunami, you should know how to assess the situation quickly.

• Try to reach the shore if you can get to high ground within ten minutes
• If you can't make it to shore safely, head for deep water as soon as possible
  • You need to be at a depth of at least 30-fathoms to stay safe from a tsunami
• Avoid entering shallow water, harbors, marinas, bays, and inlets
• Watch for debris and strong currents if you're at sea

Stay alert for changing conditions

Remember that tsunami events may last several hours. The first wave may not be the largest. Successive waves may be spaced minutes to hours apart and may continue for many hours.

• During a tsunami, there may be extended periods of strong waterflows and flooding
• Water may be full of debris
• Don't return to the coast until local authorities indicate it's safe
• Check for updated tsunami advisories, watches and warnings. Updates are usually provided every 30 to 60 minutes until an alert is canceled

After a tsunami

Don't assume a tsunami event is over until local authorities confirm that danger has passed. Tsunamis can be deceptive. A large surge may come well after the event appears to be over. It's important to stay vigilant.

• Continue to take precautions and follow directions from local authorities
• If you're safe, stay and wait for instructions from local authorities
• Return to the coast only after local authorities tell you it's safe
• Stay alert for secondary hazards including:
  • earthquake aftershocks
  • landslides
  • flooding
  • damaged buildings and roads
  • coastal flooding and storm surges