Right now tsunamis and earthquakes are right at the top of people’s minds. Our greatest tsunami threat for much of the North Island comes from the Hikurangi subduction zone off our East Coast, where the Pacific Plate is being forced under the Australian Plate. If this fault line ruptures, the only warning you might get of a tsunami would be from the shaking of the earthquake itself. The first wave may arrive in as little as 10 minutes, so there is no time to wait for an official warning. Kapiti and Porirua could similarly face a tsunami threat from their offshore fault lines.
If you are at the coast or are in a tsunami evacuation zone, and you feel a LONG earthquake that lasts for a minute or longer, OR a STRONG earthquake that makes it hard to stand up, that’s the only notification you need, and may be the only notification that you will get that there could be a tsunami on the way.
DON’T WAIT for further instructions, for your phone to beep, or other notifications or advice, a message on the radio, or something on Facebook, evacuate immediately on foot to high ground, past the blue lines if they are in your area, as soon as the shaking has stopped.
Check out the tsunami evacuation zones now, so that you aren’t trying to find out if you are in a tsunami evacuation zone just after the earthquake when there may be no power or internet. Look for where you live, work or play, and the places you often visit or pass through.
We have brand new tsunami evacuation zone maps available for the region, covering our entire coastline. The maps are all available as JPGs and PDFs that you can print at www.getprepared.org.nz/tz . There’s also a searchable map of the region, where you enter an address to see if it’s in a zone.
The different zones are colour coded so that officials can tell you which particular areas they need you to evacuate from after an earthquake overseas, such as from Chile, produces a tsunami that could affect us. In these cases, there would be many hours to coordinate an evacuation – officials may say to stay out of the Red Zone (the beach and some very low lying areas), or if it’s big enough, the Red and Orange Zones. But if you feel any long or strong earthquake, you should immediately evacuate all of them, the Red, Orange and Yellow Zones, without waiting to be told to.
These maps were developed using computer modelling of the behaviour of tsunami waves on our coastlines by GNS Science, and the Yellow Zone covers the worst case credible scenario for tsunami that could impact our region. Where they have been painted, the Blue Lines indicate the edge of the Yellow Zone, so head uphill past them to get out of the zone.
The key message remains, if it’s long or strong, be gone.