The Local Government Commission is to give its verdict today on whether the nine councils in the Wellington region should merge into a supercity.
The commission has been considering two applications for a reshuffle of the councils for almost 18 months.
The Greater Wellington Regional Council wants a region-wide council, but councils in the Wairarapa want to stay separate.
Some of the region's mayors believe the commission would favour a supercity.
The Hutt councils have been vocal opponents, but Lower Hutt mayor Ray Wallace said that had made little difference, as the commission seemed to have its mind made up from the start.
"Word around town is that the announcement will either be a two-tier or three-tier supercity. If it is one of those options, it will be clear that the Local Government Commission hasn't been listening to the people of the region."
Wellington mayor Celia Wade-Brown also believed that the a supercity would be proposed, but felt a two-tier approach with local boards sitting under a region-wide council would complicate things.
"Having a single-tier where people are directly accountable for all the decisions would be better," she said.
However, Ms Wade Brown said the Wellington City Council supported Wairarapa's case to remain separate. They argue that they are rural communities with different needs than the rest of the region.
Carterton mayor John Booth also thought today's proposal would be for amalgamation, but was not convinced that the Local Government Commission had weighed up every option.
"Just recently when they invited us to come down, they couldn't even get the name of the applicants right. They said it was the Wairarapa Local Governance Group," he said.
"The application was made by the three Wairarapa councils, so I don't know how well they read our application."
Greater Wellington Regional Council chair Fran Wilde said the commission must have looked at all the applications, given that the decision had taken 18 months.
Ms Wilde said she expected the announcement would suggest joining the councils and hoped that would be the case.
"It enables big infrastructure and networks to be planned and delivered comprehensively," she said.
Once the draft proposal was made public, it would be open for submissions until early next year, followed by hearings for stakeholders to state their case before the final proposal is announced.
But the decision would almost certainly come down to a referendum, which could be sparked by a petition signed by 10 percent of people from any one affected area.
Mr Booth told Morning Report he wanted the town to join with South Wairarapa and Masterton, but remain separate from urban Wellington.
"We're a rural provincial area, we have a totally different set of requirements, we need rural-focused people governing our district - and I don't think we need people who think Red Bands are sunglasses."
Business supports supercity
Wellington Chamber of Commerce supports the idea of a supercity, believing it could help the region perform better economically.
"It's about making sure that we have a voice in the country, it's about making sure that we move the region forward collectively - it's not about each individual council having their own schemes, doing their own things," said Chamber president John Milford.
He told Morning Report that from 2003- 2013 the region performed worse than the national economy in indicator except one.