Under the new legislation, the local area councils recommended in the panel report are not provided for, she said, but local boards could be implemented as under the Auckland super-city legislation.
The functions of the local boards were not protected by legislation and would be delegated by the main governing body.
Another change meant the Local Government Commission would be able to implement any governance structure without a mandatory poll.
If the public wants a poll on the changes, it would have to be forced by a petition which would have to be signed by 10 per cent of the affected area within a specific timeframe.
Mrs Patterson said "grass roots democracy" would diminish under the changes.
"The decision for people of the Wairarapa is do they want to be part of a Wellington super city or a Wairarapa unitary authority?"
Local Government Minister David Carter said the bill refocused the purpose of local government, introduced financial prudence requirements for local authorities, strengthened council governance provisions and streamlined council reorganisation procedures.
"The reforms will help the local government sector play its part in growing the New Zealand economy. Communities, businesses and households all stand to benefit from these changes," he said.
Last week, GWRC chair Fran Wilde said a Supplementary Order Paper presented to parliament supported many of the major recommendations in the panel report.
Greater Wellington councillor Daran Ponter disagreed, saying it would not allow for the two-tier structure advocated.
"The SOP provides for the Auckland model only - not a situation which Wellingtonians will embrace," said Mr Ponter.
