Billions of dollars worth of infrastructure is at risk from climate change but there is no national plan to deal with rising sea levels or extreme weather events, a new report shows.
The Climate Change Adaptation Technical Advisory Group stocktake report says while New Zealand has significant knowledge about climate change, there were gaps about what was happening and how to adapt.
It also said there was a lack of co-ordination in how local councils, businesses and communities would manage climate change impacts.
"Information is either not accessible to decision-makers, decision-makers do not have the capacity or capability to make decisions, or they are not able to prioritise adaptation action based on current information," the report said.
It said agencies tended to respond to significant events, such as drought or flooding, rather than preparing for them.
Climate Change Minister James Shaw said while it made for grim reading, he hoped the report would be useful.
"We are already having more severe flood events, more frequent flood events, storms, droughts, which are more frequent and more severe and so on. So it is really important that we get ahead of this before it really starts to bite."
The report said 68,000 buildings were at risk of sea level rise, with a replacement cost of $19 billion.
Five regional airports, 46km of railway and 1100km of roads were also exposed.
Mr Shaw said local councils would be at the forefront of plans to deal with the risks.
"If we're building new railways or new roads or new subdivisions or apartment buildings or airports, it gives us a decision-making framework to say, well how do we ensure that we're not pouring billions of dollars into new stuff that we're then going to have to write-off only a decade or two down the track."
Local government New Zealand president Dave Cull said councils had been crying out for that information for years.
"We should be cognisant of the seriousness of the issues confronting us but there's no point in being daunted, we've got to confront it."
He said the government needed to set up a risk agency for local government around climate change impacts.
"We already told the government that we want to work with them in a collaborative way to develop planning and to identify what effects different communities and different councils will have to confront, then on the basis of that you can do some planning around your finances, etc."
Environmental defence society chief executive Gary Taylor said the report was a big wake up call and New Zealand was lagging in climate change preparedness.
"We've seen a lot of coastal inundation, particularly around Dunedin for example, which has been unplanned for. We've got a lot of managed retreat from rising sea levels and stormwater surges happening in other parts of the country.
"This is all pretty uncoordinated."
The government's also released a report on coastal hazards and how councils should deal with them.
The Climate Change Adaptation Technical Advisory Group will make recommendations in March on how New Zealand can adapt to the impacts of climate change.