Climate Change Minister James Shaw released the report on Wednesday, which sets out a six-year plan to embed adaptation to global warming into policies and legislation.
"Frankly, it is an astonishingly complex area of public policy to work through," he said.
Among the proposals, councils will need to provide homeowners and buyers with their assessment of how the changing climate might impact their property.
Around one in seven New Zealanders live in flood-prone areas, according to the report, and over 70,000 are threatened by sea-level rises.
"That's just coastal areas. We don't have quite as good data on river and floodplains and so on," he said.
"There's a significant number and it's not confined just to houses. There are farms, commercial property, public infrastructure."
Mr Shaw was expected to outline a process for "managed retreat" in the report, where at-risk communities are asked to leave their homes due to extreme weather events.
One managed retreat has already taken place, the coastal town of Matata in Bay of Plenty, which battled with landslips and debris under heavy rain.
The 34 property owners were forced into a buyout after the council deemed their homes unsafe, and uninsurable.
Other communities, including Westport, built on a floodplain in South Island's wet west coast, and Tokomaru Bay in the remote Tairawhiti region of North Island, have been mooted for similar action.
Mr Shaw said the difficulty of making those assessments alongside different government workstreams meant there was not yet a policy or formula on moving at-risk community - or who pays.
"The risk and the cost has to be appropriately shared between the property owner, their insurance company, their bank, local government and central government," he said.
"We are seeing some real tensions, over the course of the last year, repeated flood events and associated insurance claims in a number of areas like Tairawhiti or Westport.
"We're trying to develop a solution to deal with (those places) as the most immediate challenge.
"We'll take lessons from that and apply it to other parts of the challenge, whether it's coastal or drought risk or so on ... and we have to make sure we're building in the right place in the future."
The report comes amid speculation on the political future of Mr Shaw, who was a Greens co-leader from 2015 until last month.
The 49-year-old failed to meet a 75 per cent satisfaction rating among grassroots Greens delegates at the party's AGM a fortnight ago, which stripped him of his leadership role.
All other Greens MPs have ruled out a tilt, but Mr Shaw - who is re-contending for the job - could still face a challenge from grassroots members.
Mr Shaw said he was unaware of any other applicants ahead of the nomination deadline on Thursday.
The climate adaptation plan sits alongside other a plethora of other government efforts to track and curb greenhouse gas emissions.
New Zealand has an emissions trading scheme, legislated in 2008, as its primary tool to cut emissions, and under Jacinda Ardern's government, has a goal to plant one billion trees between 2018 and 2028.
In 2019, the government legislated its Paris Agreement targets in the Zero Carbon Act, which also established an independent climate change commission.
Earlier this year, the government delivered its first emissions reductions plan, as required by the Zero Carbon Act, setting aside $NZ2.9 billion for a variety of initiatives.
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