GNS Science has made some alarming predictions about what could happen if there is movement on New Zealand's active fault line - the Hikurangi subduction zone.
It predicts there could be 1000 deaths, about 10,000 injuries and extensive destruction along the east coast of the North Island.
The prediction is based on a hypothetical scenario and is not designed to scaremonger but to guide our response plan.
- Earthquake research deemed problematic by Kiwi experts
- Alpine Fault quake: Is the big one coming?
- 'Significant' NZ research reveals 'clear link' between earthquakes and climate change
"For an event of this scale, we will never be totally prepared, but we can do as much as we can between now and then," says Jeremy Holmes, of the Wellington Region Emergency Management Office.
If a magnitude 8.9 quake hit the North Island's east coast the impacts predicted would be like nothing we've ever seen before, dwarfing those of previous earthquakes in Napier and Christchurch.
"The reality is these sorts of events occur in a sort of thousands of years, but it could conceivably happen tomorrow, it is something we need to be concerned about," says Holmes.
According to the report's scenario in Wellington, almost all buildings suffer damage and 50 would collapse. The first tsunami reaches the south coast after 10 minutes, inundating the southern end of the runway and washing boats onshore.
Fires break out, 500 people are killed another 500 are injured.
In Napier, it's only marginally better. Ten buildings collapse and liquefaction is widespread.
The first wave hits the coast after 20 minutes, causing major flooding.
The town is cut off by road and rail and the airport is unusable.
Around 200 people die, 700 are injured.
Further up the coast and up to 20 buildings collapse in Gisborne, while landslides cut off all highways.
The quake is once again followed by a series of tsunami waves, destroying the State Highway 35 bridge and badly damaging the port.
About 90 people die and 500 are injured.
"It is about understanding if you live in an inundation area, what you're evacuation route could be and practising that evacuation route as well," says Ian Macdonald, group manager at the Hawke's Bay Civil Defence Emergency Management group.
And while New Zealanders aren't too worried, they are aware.
"We've got water containers and things at home in our garage ready to go," one person told Newshub.
"I have a full emergency kit with all sorts of long-life food and that in it," said another.
And if scientists are right, it's not a matter of if those preparations are needed - but when.
Newshub.
