Town and parish councillors fear the Breckland area will be starved of green open spaces over the next 20 years because of a private sector cash injection.
The district council wants a commercial partner to put down a multi-million pound figure to refurbish and develop their land and properties, which they say will, in turn, protect front-line services.
The scheme, called a local asset backed vehicle (LABV), combines private sector money and skills with public sector assets.
Breckland Council owns assets in towns including Dereham, Watton, Swaffham, Thetford and Attleborough and has identified eight priority sites to be worked on in the next five years and a further 20 over the next two decades.
By developing leisure, shops and housing Breckland say they will build 492 homes and create 1,268 jobs over the next 15 to 20 years.
But town and parish councillors have expressed fears that the scheme could build on green spaces used by the community without replacing them.
Breckland councillor and Dereham mayor Kate Millbank said there was a 'massive deficit' in Dereham for open space, with 80pc of householders not living near a play area.
'Any loss of existing open space through the LABV project could have a negative impact on the town,' she said.
'If it is the case that some of the open spaces being proposed for development are not valued by the local community then there is a potential project to develop the sites and purchase more open space somewhere else, but the community value of these sites has not yet been established.'
And although all projects are subject to the usual planning processes, chairman of Swanton Morley parish council, Roger Atterwill, said: 'Breckland can't guarantee to people they're not going to build on a piece of green open space against the wishes of the people of the community.
'The more of these green open spaces we develop, the more that there is in the council's coffers.'
One of the green spaces which could be developed is Oakwood Road in Dereham, which is named after the impressive ancient oak which stands in the middle of the grassed area.
Dereham town councillor Tim Birt said: 'This seems a ridiculous site to be developing, with some trees which are a couple of hundred years old.
'It is one of those areas which has got housing around it and it is a public space, and that is what makes this a nice place to live.'
Mark Kiddle-Morris, Breckland's executive member for assets and strategic development, said the council would not be able to build on green spaces without creating more for the community.
'We are a rural district spread over a few miles. A lot of the LABVs are town centres so we had to make an offer to any contractor very attractive by putting in lots of land.
'We are allowed to build on open spaces if we create more open spaces.'
The authority hopes the partnership will maintain and increase the money it makes from its properties, and therefore prevent the need for service cuts or council tax increases.
Both parties share the benefits of the development, usually 50/50, and Breckland insists there are strong safeguards, including legal ones, in place for the council to be protected if the partnership fails.
But changes in market conditions could result in higher development costs and lower residential or commercial values could restrict the profits.
Michael Wassell (pictured), leader of Breckland Council, said: 'Against a backdrop of central government cuts, the council wants to maximise income from the growth we will experience in the district,' he said.
'The LABV is one of the projects the council is working on to help achieve this.
'In terms of green spaces we are constrained by the fact of not having a five year building supply.
'Where ever you are in terms of pieces of land there's always the danger that some will come in and put a planning application.
'But anything that comes to Breckland will always come to the planning committee. LABVs are no different.'
What do you think? Email EDP letters@archant.co.uk or write to EDP Letters, Prospect House, Rouen Road, Norwich NR1 1RE giving your full name and address.
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