Auckland Council is sneaking changes to the city's Unitary Plan through the back door, community groups say, after a last-minute proposal to re-zone more land for intensive housing.
After four years in the making the 30 year blueprint for Auckland's future is due to be considered by an independent panel next year.
But having settled housing densities in 2013, the council has been reworking the zoning map after early feedback from the panel argued the plan did not provide enough housing capacity.
Under the proposed changes, the proportion of residential areas zoned for single dwellings would fall from 31 percent, to just over 26 percent.
The other big proposed change was in the mixed housing urban zone, which allowed for medium-density of up to three storeys high - to increase from 11 percent of Auckland to 17 percent.
Spokesman for lobby group Auckland 2040 Richard Burton said the council should not be suggesting such large changes after the period of public consultation had passed.
"These are large areas that have been zoned without any submission asking for it - so completely by the council, in secret, no participation, no rights of submission, no rights of hearing."
The proposals reversed changes the council made when it was developing the draft plan, when it scrapped increased density rules in response to public feedback, Mr Burton said.
Character Coalition spokeswoman Sally Hughes said her group was alarmed by the scale of the changes.
The coalition was not opposed to greater housing density, but it should have been up to local communities to say where that should have happened, Ms Hughes said.
"Almost all areas have areas that are suitable for intensification.
"It's not saying whole suburbs need to be left alone, but people want a say about where the intensity is suitable in their area, and that's what this process has never allowed," she said.
Property Council chief executive Connal Townsend said Aucklanders were in favour of density before the Unitary Plan was developed.
"Once the Unitary Plan came out and we actually saw what density would actually looks like, a majority of Aucklanders then decided they were opposed to density," Mr Townsend said.
"The problem is those people were also opposed to sprawl - in fact they were opposed to actually solving our housing crisis."
The public was already consulted extensively while the council was creating the draft Unitary Plan, he said.
"The hearings panel [has] come down with a view to say, 'We understand people not wanting greater density, but we've got a massive demographic problem and we've got a huge housing un-affordability problem - we're going to have to take some action.'"
The proposals go before the independent hearing panel in March, and it will make a decision by July.