Thousands accessing Auckland flood maps every day

Wednesday, 13 August 2025

Last year the were more than 780,000 visits to Auckland Council’s flood viewer ‒ 2000-plus visits a day.

New Zealand’s largest city experienced shock flooding on its anniversary day in early 2023, which has left a legacy of anxiety when storms hit.

And that appears to have resulted in many renters and home buyers using Auckland Council’s flood viewer to check out the risk the properties they are interested in buying, or renting.

The anniversary weekend floods and Cyclone Gabrielle resulted in 15 deaths, thousands of evacuations and significant damage to homes, businesses, and infrastructure, with an estimated economic cost to New Zealand of up to $14.5 billion.

Nick Brown, Auckland Council’s Healthy Waters head of intelligence, said: “Anecdotally, we are hearing from real estate agents saying that even when people are going to look at houses on a hilltop, where it’s downhill in all directions, they’re still asking the question about flooding.

“Lots of flooding occurred, it is still in people’s consciousness in Auckland,” he said, adding the council had also been driving that awareness through targeted advertising campaigns.

In the past two decades there had been a quantum leap forward in the city’s waterflow and floodplain data with advances in aerial laser surveying, and computer modelling.

In 2013, complete flood data for the city became publicly available, but the big leap forward in usage came in August 2023 when the council made it available in a format that could be accessed on mobile phones.

Nancy Baines, senior Healthy Waters specialist, said while this information was already available, the council wanted to make it as easy as possible, not just for buyers. “Renters are really key. They move a lot, and they don’t pay for a LIM because they’re moving so often, and it’s expensive. That was a really key audience that we wanted to try and make sure got this important information.”

A LIM is a land information memorandum containing information about properties, including exposure to natural hazards like periodic flooding.

As well as buyers and renters, the council hoped the flood viewer, which can be searched by people entering addresses, or zooming in on properties, would help owners of homes to understand their risks, and then take action, if they found they were at risk.

Last year, a survey published by the country’s largest insurer IAG indicated nearly nine in 10 people looking to buy a home were paying attention to natural hazard risks like flooding when they were house-hunting, up from just 55% before the 2023 flooding.

Kelvin Davidson, chief economist from property research company CoreLogic, said while there may be a lot of interest from homebuyers in flood information, as yet, he had seen no evidence of any impact on house prices.

“It’s not clear from the most recent pricing data that there is a pricing impact,” he said.

There was some past evidence that flooding did impact house prices, but memories faded relatively quickly.

Davidson said after flooding in Dunedin in 2022 there was a price effect, but it disappeared over time.

However, Davidson said, there was a rising issue about insurability of homes.

Lead by insurer Tower, insurers have been moving to greater risk-based pricing for individual homes.

Buyers who had to pay more to insure a home could afford lower mortgage repayments than people buying less hazard-prone homes with cheaper premiums, Davidson said.

Data on flood, and other hazards like earthquakes, is becoming increasingly easily available.

It’s one of the things that needed to happen in New Zealand as the country readies for increasing climate change, according to a report published in July by the Independent Reference Group on Climate Adaptation headed by Matt Whineray, former chief executive of the Guardians of New Zealand Superannuation.

“One of the most important recommendations in the Independent Reference Group report is the call to invest in publicly accessible natural hazard and climate risk data,” said Jimmy Higgins, chief executive of Suncorp, which owns Vero and majority-owns AA Insurance.

“This is a crucial first step toward a fairer, more informed system, and it’s a step that we can take right now,” he said.

Higgins was a member of the seven-member Independent Reference Group.

Earlier this month, Auckland Council launched a coastal monitoring portal, which Aucklanders could use to access data like sand levels, coastal camera imagery, and wave and water levels at key Auckland beaches.

“The Matt Whineray report into adaptation came out about three weeks ago, saying, ‘How do we get more information out to the public so people can make informed decisions about the risks that they are taking when they choose to live in an area?”

There’s another group with a growing interest in the subject: Banks.

Westpac indicated the direction of travel earlier this year as it went in search of a new strategic insurance partner to help it make lending decisions that better take into account natural hazard risks like flooding.

Already banks track the proportion of the properties that are security on loans they have made that are at risk of flooding during periods of high rainfall.

Speaking to The Post in May, Westpac chief executive Catherine McGrath said people buying homes were now very conscious of natural hazard risk.

“I think the way that we get through all of this together … is with data,” McGrath said.