Campaigners have vowed to make a “compelling case” to the government’s planning inspector against building on the green belt.
An eight-week publication period on the St Helens Local Plan submission draft is currently open to allow members of the public to submit for representations.
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It is the last time members of the public will be able to officially comment on the Local Plan before it is submitted to be examined by a government planning inspector.
In Rainford, agricultural land south of Higher Lane is earmarked for up to 259 homes in the plan, with the council saying the site was put forward by its owner, Lord Derby.
Despite this, Rainford Action Group believes the site should continue to be protected and said it has enlisted expert advice to help with its representation.
James Wright, Rainford Action Group chairman said: “We’re putting together a robust response to the plan and believe we have a compelling case that destroying protected land is unjustified.
“With Brexit now days away, the ability to grow our own food in this country has never been more important so destroying some of the most fertile land in the country would be reckless in the extreme.
“And with each new day bringing fresh details of the climate crisis our planet faces, we should be looking to save rural land not build on it.
“We hope as many people as possible respond to the planning inspector and point out the obvious flaws in this latest plan.”
The St Helens Local Plan sets out the framework for the growth and development of the borough up until 2035.
One of the reasons green belt sites have been allocated for development in the plan is down to a lack of feasible brownfield sites in the borough.
Since elected as leader of the council last May, Derek Long has stressed the council will adopt a brownfield-first policy as part of a balanced Local Plan.
However, many of the brownfield sites known in the borough are contaminated due to its previous use.
The government used to provide funding to bring these sites back into use, but this has now stopped.
The council estimated that much of the remaining brownfield land feasible for development requires funding in excess of £40 million to be brought back into use.
Despite this, the council has to meet national housing targets as part of a drive to build 300,000 homes per year.
The submission draft Local Plan proposes delivery of 486 per annum, which takes into account increased housing need due to employment growth.
Following the current publication period, the submission draft will be submitted, together with the representations received during this publication consultation, to the Secretary of State for Housing, Communities and Local Government for independent examination.
St Helens Council intends to adopt the Local Plan in 2020.