Canterbury’s coastline is exposed to tsunamis – long, powerful waves created by a sudden disturbance in the sea or a lake – created both close to shore or across the Pacific Ocean. Our biggest tsunami threats are tsunamis created by large earthquakes on the Hikurangi or Kermadec subduction zones, to the east and north of the North Island, or on the Puysegur subduction zone to the south of the South Island, or by large earthquakes off the coasts of Central or South America. Where a tsunami comes from determines how much, and what kind of warning we get.
Most tsunamis that arrive at our shores will not flood land but can still cause unpredictable and dangerous currents and surges in the water and on beaches. Occasionally though a large tsunami that could flood land will arrive, and you don't want to be in its way.
Remember: Long or Strong, Get Gone! If you feel a long earthquake that goes for more than a minute, or an earthquake so strong that it is hard to stand up, move out of Canterbury’s red and orange evacuation zones, or away from any lake shore, as soon as the shaking stops. Do not wait for anyone else to tell you what to do. There will not be enough time for an official warning if the tsunami is coming from close by.
move to the nearest high ground, or out of the red and orange tsunami evacuation zones in Canterbury. Do not wait for anyone to tell you what to do.
Tsunamis are not like regular waves. Just check out this video of one of the 2010 Chile tsunami waves coming into the Avon Heathcote Estuary (Ihutai) – it doesn’t look that high, but it packs a punch.