The Wellington Regional Council has urged the Local Government Commission to stick with its proposal to merge the region's nine councils.
The comment came at the second day of public hearings on the plan, which would create one Greater Wellington Council with a mayor at large and 21 councillors.
Each ward would also have its own local board.
Regional council chair Fran Wilde said splitting the authorities geographically, such as the Wairarapa, wouldn't work.
"All of the land management, water management, environmental management, flood management which goes in through different areas - that would be worse than the current situation.
"The current situation, with a regional council, is better than separate unitaries."
Ms Wilde said the commission should clear up the role of local boards in any final proposal, because people were still scared they would not have clout.