The idea of special economic zones - which could suspend rules for the environment, overseas investment and possibly immigration - is getting strong support from local government.

Photo: Supplied: Jake Osborne

The government asked the Ministry of Business, Innovation and Employment (MBIE) to investigate the zones, which it believes will encourage economic and job growth in the regions.

Official documents released to Forest and Bird show that both Bill English and Steven Joyce, in their previous roles as Finance and Economic Development Ministers, were interested in a model which would provide 'regulatory relief'.

The model focused on streamlining laws so investment could be quicker and have more certainty, and the Resource Management and Overseas Investment Acts were in the spotlight.

Local Government NZ chief executive Malcolm Alexander said the zones had merit and were worth exploring in areas such as overseas investment.

"Maybe the rules around overseas investment are suspended in one area to encourage certain projects to come through to generate jobs. That will have controversy for some areas but that's potentially another one that could work."

Mr Alexander said the zones would be a way of trialling an idea which could generate growth in the regions.

His organisation particularly liked the idea of using the zones to introduce a visitor levy in places like Queenstown, and he said the zones would require legislation and safeguards and be a matter for debate in Parliament.

Photo: Supplied: Jake Osborne

Local case studies explored

The documents showed MBIE looked at case studies of zones around the regions, including aquaculture in Southland, where Stewart Island is a focus for development, particularly salmon farms.

It noted finding sites for aquaculture development in Stewart Island had been challenging, and ministers had investigated Port Pegasus as a potential site.

However, MBIE noted the area contained some of the largest areas of near pristine marine habitat in the country with "significant natural heritage values".

The advice showed salmon farming would be inappropriate in this area under the Resource Management Act (RMA), but the documents say a special economic zone with significant powers could be used to "override RMA issues".

But it is noted that an intervention of this type would risk the social licence of the project, and that there could be other regulatory barriers, such as fishery and conservation requirements.

The Environmental Defence Society previously fought the development of four salmon farms in Marlborough, and won a Supreme Court ruling over the development which reduced it to three farms, and resulted in a landmark decision, saying the RMA had an environmental bottom line.

Chief executive Gary Taylor said the zones were a bad idea and a way of the government fast-tracking projects which were unlikely to get the go ahead under the law.

Forest and Bird chief executive Kevin Hague agreed, "government is essentially saying that it will create zones where New Zealand law which has gone through appropriate process to be developed in the first place, with appropriate public consultation, will be suspended in these places."

Prime Minister Bill English said the zones were nothing new or behind the scenes.

He said it was an ongoing discussion and the public would have a say if they got the go ahead.

"Well obviously they would... it's just part of the government trying to invest in work to support economic success and any policy's open to debate."

The government could not say when it might make up its mind about whether or not to introduce the special economic zones.