Photo: RNZ / Cole Eastham-Farrelly
Moves are afoot to let you know more about the flood hazards posed to the house you are looking at buying.
It is too late for householders dealing with floods right now in the upper North Island, but the combination of science and law are working together to take out that "if only I had known" factor.
First up is a law change in the works to force councils that do not provide enough info on flooding and earthquakes to do more.
For Gillian Blythe, head of industry group Water New Zealand, it can't come soon enough.
"Not every land information report [LIM] has information about floods and climate change hazard," she said.
"All householders and businesses want to understand that hazard information. It must be reported in a nationally consistent and transparent way."
Submissions on the bill closed in early February.
Some people whose property values might be lowered if flood information was put on LIMs have, in the past, opposed this - but it is vital, as long as it is correct, Blythe said.
"Law changes requiring that level of transparency is really important, but you can't provide transparency if you don't have data. So you need flood data."
That's where Dr Emily Lane comes in. The NIWA scientist is just over a year into leading the first national project to draw up the sort of flood maps that her agency four years ago said were urgently needed.
"People will actually be able to know what their flood hazard is beforehand," she said.
"It will take a little bit of time because obviously, you know, people need to understand, 'This is my flood hazard.' But with events like this happening, people are more aware of flood hazard."
Major centres typically had more flood maps than smaller places, but even then they were not consistent.
Her team will have its first nationally consistent version ready in about a year, and within two years it should be flexible enough to adapt to the vagaries of climate change.
"As we've seen an Auckland, there are places that are suddenly going to be flooded and it's going to be hard.
"But it's important that we actually understand this, where possible, if we start moving people away before they experience that flood rather than waiting till it happens."
The Insurance Council's Tim Grafton witnessed the reality of the hazards on a stormy Whangaparāoa peninsula out of his own window.
"My greatest hope is that from the two weather bombs we see some concerted action to build resilience," he said.
House buyers should be asking sellers if they'd had a flood before, and when, while they wait over the next several years for the science of flood mapping to catch up with the law around clearer LIMs, Grafton said.
"Standard national flood maps around the country would be great - if you can identify the risks, you know, you're going in eyes wide open whether to purchase a property."
The flood mapping project has five streams, that include Lane looking at where the hazards are, others looking at what floods and others at who is hit in different ways.
Among the other national initiatives underway is tougher scrutiny by Taumata Arowai of wastewater systems.