The Local Green Space concept was introduced in the National Planning Policy Framework in 2012, but was never clearly defined, something the society hoped the Housing White Paper, currently out for consultation, would do.
Case officer Nicola Hodgson said: "While Local Green Space is an excellent concept, there has never been a clear process for its designation, nor is there guidance on how it should be managed, enforced and protected.
"The NPPF only affords Local Green Space the same protection as green belt, which is itself threatened, and Local Green Space confers no rights of access for the public.
"We hoped that the Housing White Paper would take the opportunity to set these things out, so that Local Green Space could be a clear part of the planning process. Instead, we fear that it will be undermined. Every planning authority seems to have a different interpretation of the meaning of Local Green Space and of designating it, and even when local people have applied for land to be designated as Local Green Space there is nothing to stop a planning application from being considered and determined.
"We also believe that where land has been designated as Local Green Space, its protection will be weakened by the proposals in the White Paper to allocate sites for development in the green belt through neighbourhood plans. We have argued that, if green belt is to be developed, additional green accessible space should be made available."
She said the society had reminded the Department of Communities and Local Government that Natural England has previously said there should be accessible natural green space within 300 metres of where people live.
The Open Spaces Society was founded in 1865 and is Britain’s oldest national conservation body