Insurance premiums won’t fall in NZ’s capital despite research showing the chances of a major earthquake rupturing on the Wellington fault line have halved.

The “it’s our fault” project, conducted by NZ Government-owned research organisation GNS Science, has found the major fault running through the city is 50% less likely to crack and produce a magnitude 7.5 quake in the next 100 years than previously thought.

Until recently, evidence has suggested the segment ruptures every 600 years, with the last major quake 450 years ago at magnitude 7. The new findings show it ruptures every 900 years and the last earthquake was 300 years ago.  

“For some years we have suspected that Wellington’s reputation for being ‘overdue for the big one’ was an exaggeration,” Project Leader Russ Van Dissen said.

But he says earthquakes will still occur in the region and the need to be prepared remains the same. Wellington residents can expect several magnitude 6 to 6.9 earthquakes in their lifetime.

Insurance Council of NZ CEO Chris Ryan told insuranceNEWS.com.au the report is significant for reinsurers but doesn’t necessarily reduce the risk of losses for insurers.

“The reality is there’ll be no real change in terms of premiums for New Zealanders,” he said. “There are still going to be a large number of minor or lesser earthquakes that can potentially cause a lot of damage.

“The nature of earthquakes is not just their size but their make-up – whether they’re shakers or rollers, how deep in the earth’s crust they are and where they are located. Those risks remain and in terms of premiums there’s unlikely to be any immediate change.”