Civil Defence Emergency Management groups from across the East Coast of the North Island are developing an emergency plan in response to a rupture of New Zealand’s largest fault - the Hikurangi subduction zone.
Using a credible magnitude 8.9 earthquake and tsunami scenario, the groups are discussing how to enhance communities' preparedness for such an event.
Project leader Natasha Goldring says building the collaborative response plan was vital in lifting readiness for, and resilience to a future earthquake and tsunami on the Hikurangi fault.
“The scenario we are using to support the development of this response plan is a very realistic example of what we could face in our lifetime, or that of our children and grandchildren,” Ms Goldring said.
She says people still need to make sure they understand the risks they face and take the necessary steps to prepare themselves.
“Communities are at the centre of all response planning, and we want this project to be a collaborative effort. We are all responsible for ourselves and our families – we are all part of Civil Defence in New Zealand.”
The launch of the project comes in response to research over the last several years which is suggesting the likelihood of a rupture may be higher than initially understood.
GNS Scientist, Dr Laura Wallace, attributes this to a combination of factors, including new insights gained following the Kaikoura earthquakes, evidence for pressure building on the fault, and geological evidence for prehistoric earthquakes on the subduction zone.
“A subduction zone is where one tectonic plate subducts (dives) underneath another - the boundary between these two plates forms a large fault. This one in particular runs offshore from the east of Gisborne down to the top of the South Island and poses a significant earthquake and tsunami risk to the entire east coast of New Zealand.”
She said subduction zone faults had been responsible for most of the world’s deadliest earthquakes and tsunamis to date, with Japan 2011 being the most recent example.
“We know the Hikurangi subduction zone can produce large earthquakes and tsunamis, and these events have happened in the past.
“While we’re carrying out more research to build a clearer picture of the hazard posed by the Hikurangi fault, we know a rupture at some point in the future is certain.”