A proposal to buy at-risk homes will provide more certainty and reassurance to residents, a council group says.
The densely populated South Dunedin area is built on a former coastal wetland, is low lying and is at risk from climate change, rising groundwater, and other hazards.
The Dunedin City Council has started discussions with Treasury about a voluntary scheme where properties could be bought on the open market and used for climate adaptation projects.
They could then be used for more resilient housing developments, wetlands or other adaptation projects in the future.
It was estimated to cost up to $132 million over an initial five-year period based on buying 65 properties a year.
South Dunedin Future is a collaboration between the Dunedin City Council and the Otago Regional Council to develop a climate change adaptation strategy with the community over the next few years.
Programme manager Jonathan Rowe said this approach would help the community to tackle the problem and provide much sought-after reassurance.
The proposal was developed following feedback from residents, he said.
"If you start to acquire property on the open market, it comes up a rate that's voluntary, right? It's people putting their homes on the market to sell so it's not compulsory. You're not forcing anyone out. You're not doing red-zoning or red-stickering which is a big concern we've heard from the community and something we want to avoid."
It was better to act earlier than wait for a disaster to potentially force their hand, he said.
"Could you get ahead of that curve? Could you start looking at buying property while it still has some value, keep it on the market in terms of housing supply? Could you rent it? Can that provide a revenue stream to the councils or whoever has purchased it, which then kind of offsets some of your costs?"
By the end of the year, a list of potential solutions is expected to go to the Dunedin City Council for approval to consult the community early next year.
"So that list is that kind of full spectrum of fight or flight so building hard infrastructure protections like pumps, pipes, seawalls, nature-based solutions like parks, wetlands, open watercourses - that sort of thing.
"And also managed retreat and relocation so moving people out of harm's way into areas that are lower risk, even new resilient housing development."
'Overkill by the council'
Greater South Dunedin Action Group chair Ray Macleod said the council should have spoken to locals first.
He was concerned the proposal would stress out residents and affect their ability to sell.
"The property acquisitions may be voluntary but those properties will be identified and that would materially affect the welfare potentially and the wellbeing of the people that own them because they would become unmerchantable on the market."
Residents would be more uncertain and concerned about whether they should fix their house up, sell it, the value and how that has been affected, and whether there would be any consequences from the banks if they didn't have the same security over the property, he said.
Other solutions should be prioritised before looking to buy land, although some land might be needed for projects in the future, he said.
"I think it's an overkill by the council in respect to a number of things. One is I think they should be seriously examining engineering solutions in the medium term rather than property acquisitions."
Rowe said they would be talking through the community's concerns at public meetings and events held in the next month or so.
"It's always a balancing act around how early you talk to the community on some of this stuff. Sometimes you need to develop an idea or a proposal to a point where you think it might be a goer before you start talking more widely."
The events include a Meet the Scientists night on 13 September at Nations Church from 7pm to 9pm, a street meet and sausage sizzle at the main shopping strip on King Edward Street on 23 September from 10am to 2pm, and another evening meeting at the Dunedin Gasworks Museum on 10 October from 7pm to 9pm.
'The name of the game is to get ahead of the situation' - mayor
Dunedin mayor Jules Radich said a lot of the properties in south Dunedin could really do with a land-use change.
"The name of the game is to get ahead of the situation," Radich said.
A scheme was worked out in which people were offered a financial arrangement, he said.
"It's certainly based on funding and getting ahead of the whole situation. Our expectation is that overtime it would be self-funding."
Radich said in its first year the council would need $25 million in support from the government.
The government was thinking about the council's pitch, he said.
"We've got a range of adaptations to adapt the landscape for climate change so whether they're ponds or pumping areas or wetlands or just the type of housing that's there is made more resilient."
The council was not trying got change an area all at once but in a gradual way and this would be cheaper in the long run, he said.