A tsunami is a series of powerful waves caused by a sudden movement of the sea or lake floor or by something falling into the water. Most tsunamis are caused by large underwater earthquakes, but they can also be caused by volcanic eruptions or underwater landslides.

Find information about where tsunamis come from and Waitaha/Canterbury's tsunami warning systems and evacuation zones.

Tsunami hazards

The entire Waitaha coast is at risk from tsunamis. Find out more about their origins and characteristics.