The unusually soggy winter, which also finished up at a record 1.4C above normal, was put down to a mix of local, regional and global climate drivers, from warmer coastal waters to La Niña and climate change.
It continued a troubling trend for our insurance sector, which had already paid out close to $200m in extreme weather claims in the year to June.
The latest tracker report, released today, also included a nationwide poll that found 82 per cent of people feel these wild events are growing worse and more common, while 69 per cent were worried about the impacts of climate change.
But 42 per cent felt poorly prepared for them – and a similar proportion had taken recent steps to better protect themselves.
"What the Tracker clearly shows us is that despite high levels of concern, awareness and property damage, people do not feel prepared and little action is occurring to help people protect themselves," said the insurers' chief executive, Amanda Whiting.
"This could be because people don't know how to prepare, or simply hope it won't happen to them."
In August, the companies proposed a three-step plan to the Government to address flood risk.
"We need to work collectively and urgently to better protect people and property in our most at-risk communities," Whiting said.
"That means agreeing a common view of which communities are at the highest risk, stopping further development and intensification in high-risk areas, and investing in infrastructure to protect our most flood-prone communities."
IAG was meanwhile eyeing more risk-based pricing to avoid customers in low-risk areas subsidising those in high-risk ones – an approaching our largest general insurer, Tower, has also been taking.
After last year becoming New Zealand's first insurer to introduce a new pricing model based on individual homes' risk of flooding from rainfall and rivers, and making these public, Tower was now turning to coastal erosion.
According to New Zealand's most recent risk assessment, 72,065 people live in areas exposed to once-a-century coastal inundation flood risk, while about 675,500 live in areas prone to inland flooding.
But those figures were almost certainly underestimates.
One major new sea level rise study found that, in vast swathes of our coastline, one-in-100-year extreme flooding could become an annual occurrence within two decades.
In all, rough estimates put the cost of losing properties and assets in coastal and floodplain areas threatened by climate impacts at about $145 billion.
Researchers have warned that homeowners living in seaside areas at risk of one-in-100-year flood events today could lose insurance within their lifetimes – and perhaps within the next 10 years.
Over the longer term, insurance retreat from some locations was seen as inevitable.
"The distribution of insurance claims across regions suggests that some parts of Aotearoa are already experiencing the impacts of climate change without the financial backstop of insurance," Climate Sigma's Belinda Storey said of the tracker's latest data.
"For example, the Tairawhiti region was devasted by storms in March, but the region doesn't feature in this report, presumably because much of the damage was inflicted on uninsured property."
By the numbers
• 82%: of people polled in AMI, State and NZI's latest Wild Weather Tracker believe extreme events are increasing in frequency and severity.
• 71%: agree climate change is a key contributor to wild weather, while 69% are concerned about the potential impacts of wild weather.
• 40% have taken precautions to prepare for wild weather in the past six months, while 42 per cent were either unprepared or only a little.
• 34% increase in property damage in the last six months: or 13,587 claims compared with 10,106 claims in the same period last year.
