Tsunami Preparedness

Although tsunamis are rare, it’s important to understand the impact of a tsunami on Victoria and what to do if one occurs. To learn about the risk of tsunamis in Victoria and to find out if you are in the tsunami hazard zone, check out the new interactive tsunami map for the Capital Region.  

A tsunami consists of a series of unusually large waves formed by a large-scale disturbance of water bodies. One of the primary causes of tsunamis is an earthquake, but tsunamis may also be triggered by landslides, volcanoes or explosions. Did you know that the majority of the Capital Region’s coastline is quite elevated? This means that most people are safe from the risk of tsunamis and that anyone in a low-lying tsunami hazard zone does not need to travel far to reach safety. 

Victoria is at risk of experiencing tsunami hazards from a number of potential sources including the Cascadia Subduction Zone, the Alaska-Aleutian Subduction Zone and local shallow crustal faults.

Is Victoria at risk of a tsunami?

In 2021, the Capital Region completed the Regional Coastal Flood Inundation Project to better understand the regional impacts from coastal storm flooding due to sea level rise and tsunamis.

This project used 11 different tsunami sources that may cause tsunamis in our region that were evaluated for different magnitudes and sections of the Cascadia Subduction zone, Aleutian Trench, Alaska, Haida Gwaii, Devil’s Mountain Dault and Southern Whidbey Fault. Tsunami maps were created that show the safe zones and tsunami hazard zones for all 11 sources on one map. There are other potential sources of tsunamis that were not included in this modelling and mapping project. The 11 sources modelled were chosen based on likelihood of occurrence, potential impacts, and risk. 

The main risk of a tsunami in Victoria is from a felt earthquake and, therefore, the SHAKING is your warning that a tsunami may be coming. If you feel strong shaking from an earthquake drop, cover, and hold on! Count to 60 after the shaking has stopped and then move to higher ground (tsunami safe zone) by foot or bicycle if you are in a tsunami hazard area. There is no need to drive to the top of a mountain to find safe high ground. Other signs of a tsunami may include the ocean receding, a sudden rise or fall in sea level, or a roaring sound coming from the ocean. For more information on tsunami preparedness and the tsunami safe zones in Victoria, check out this brochure [PDF - 2 MB]. To get alerts for tsunamis and other possible hazards, sign up for Vic-Alert.

For more detailed information, check out the CRD Tsunami Modelling and Mapping Report Oct 2021.

Tsunami Hazard Map

It is important to know if areas that you frequent such as your home, workplace, school, etc. are located in a tsunami hazard zone so that you can move to a tsunami safe zone in the event of a felt earthquake or tsunami warning.  Check out the City of Victoria’s interactive Tsunami Map to find out if you are in a hazard zone. Not in Victoria? Check out the Capital Region Tsunami Map

Additional Resources

Visit PreparedBC to download the Earthquake and Tsunami Guide.

Visit the National Tsunami Warning Center (NTWC) which provides tsunami warnings to California, Oregon, Washington, British Columbia, and Alaska.

British Columbia's Tsunami Notification Zones

BC's coastal communities are divided into five tsunami notification zones. Each zone includes all islands and inlets within it.

Here in the Capital Region, you may find yourself in three of the five notification zones:

  • Zone C: Outer west coast of Vancouver Island including Port Renfrew
  • Zone D: Juan de Fuca Strait from Jordan River to Greater Victoria including the Saanich Peninsula
  • Zone E: Strait of Georgia including the Gulf Islands.

When tsunami warnings, watches, or advisories are issued, they may make reference to these zones.

Tsunami Alert Levels

Tsunami notifications, such as those issued using Vic-Alert, are communicated using the four levels of tsunami alerts: warning, advisory, watch, and information statement:

Credit: National Weather Service – National Oceanic and Atmospheric Administration

Tsunami Warning – A tsunami warning is issued when a tsunami with the potential to generate widespread inundation is imminent, expected, or occurring. Warnings alert the public that dangerous coastal flooding accompanied by powerful currents is possible and may continue for several hours after initial arrival. Warnings alert emergency management officials to take action for the entire tsunami hazard zone. Appropriate actions to be taken by local officials may include the evacuation of low-lying coastal areas and the repositioning of ships to deep waters when there is time to safely do so. Warnings may be updated, adjusted geographically, downgraded, or canceled based on updated information and analysis.

Tsunami Advisory – A tsunami advisory is issued when a tsunami with the potential to generate strong currents or waves dangerous to those in or very near the water is imminent, expected, or occurring. The threat may continue for several hours after initial arrival, but significant inundation is not expected for areas under an advisory. Appropriate actions to be taken by local officials may include closing beaches, evacuating harbors and marinas, and repositioning ships to deep waters when there is time to safely do so. Advisories may be updated, adjusted geographically, upgraded to a warning, or canceled based on updated information and analysis.

Tsunami Watch – A tsunami watch is issued when a tsunami may later impact the watch area. The watch may be upgraded to a warning or advisory or canceled based on updated information and analysis. Emergency management officials and the public should prepare to take action.

Tsunami Information Statement – A tsunami information statement is issued when an earthquake or tsunami has occurred of interest to the message recipients. In most cases, information statements are issued to indicate there is no threat of a destructive basin-wide tsunami and to prevent unnecessary evacuations. Information statements for distant events requiring evaluation may be upgraded to a warning, advisory, or watch based on updated information and analysis.

cancellation is issued after an evaluation of water-level data confirms that a destructive tsunami will not impact an area under a warning, advisory, or watch or that a tsunami has diminished to a level where additional damage is not expected.