A business group says the Local Government Commission has failed the public by not promoting debate about the Wellington supercity proposal.
The Kapiti Chamber of Commerce said there had not been enough time to debate the issues, and the information was too dense for most people to engage with.
In early December, the commission released a draft plan to merge nine councils in the Wellington region.
Kapiti Chamber of Commerce Chair Liz Koh said it had failed to get the public engaged with the proposal.
She said the consultation period was too short, and had not been widely debated.
"Well unfortunately the draft proposal came out just before Christmas and of course that gets buried in the whole Christmas rush thing.
"And then we had January when people are away on holiday. It's only really left us with February to try and get some traction on this issue."
Ms Koh said it was a once in a generation opportunity, which she feared was already lost.
However, the Local Government Commission said there was strong public interest in the reforms proposed for the region.
The commission's chief executive, Sandra Preston, said it had provided plain-English material on its website and to all 36 public libraries in the region.
She said the commission agreed that public debate was vital and there have been at least 14 public meetings on the issue since January.
Last Friday, the commission announced the cost of the merger had increased 13 percent to $210 million.
The consultation period ends on 2 March, and by last Thursday, only 400 submissions had been received.