Tsunami Information

A Tsunami is a series of ocean waves that are sometimes generated at the same time as an underwater earthquake. Large underwater landslides can also displace a great deal of water and generate a tsunami. A tsunami wave can race outward in all directions at speeds of up to 800 kilometres an hour and can reach heights of six to nine metres at the shoreline.

Tsunami Wave

What Should I Know About a Tsunami?

  • They have nothing to do with the tides or the weather and act differently from ordinary waves.
  • They can move through the ocean at intense speeds and be scarcely noticeable, even when passing under a boat.
  • The first wave of a tsunami is often not the largest; others may follow for a period of several hours.
  • Their danger lies in shallow waters, near shore.
  • Heights of the waves increase as the tsunami runs into river and coastal channels.

Types of Tsunami Alerts

Alert Level

Threat

Action

WARNING

Flood wave possible

Full evacuation suggested

ADVISORY

Strong currents likely

Stay away from the shore

WATCH

Danger level not yet known

Stay alert for more information

INFORMATION STATEMENT

Minor waves at most

No action suggested

CANCELLATION

Tidal gauges show no wave activity

Confirm safety of local areas

How Can I Prepare Myself For a Tsunami?

  • Sign up for Saanich Peninsula Alert to ensure you receive critical alerts during an emergency. Information regarding sheltering in place or evacuation instructions would be delivered over Saanich Peninsula Alert.
  • Create emergency kits for the purpose of sheltering in place, and grab-and-go in the event of an evacuation
  • Make a plan that includes designated meeting places and emergency contacts

For more information, familiarize yourself with the Capital Regional District’s Tsunami Information Portal Map. This mapping tool hosts data and widgets that allow you to visualize and gain a holistic understanding of tsunami related information based on assets, data and real to near-real time events that are available. It allows residents and guests in the capital region to understand their tsunami hazard risk.

In the video below, Town of Sidney staff provide a brief demonstration on how to utilize the Capital Regional District’s Tsunami Information Portal Map, specific to Sidney.

For any further inquiries, you are welcome to contact Emergency Management staff at the Fire Department.