A planning framework which could see 2,500 homes built on the site of a once-proud agricultural college could prove "devastating" to pioneering charity work.

Campaigners fear the expansion plans of Hannahs, a first class facility run by disability charity the Dame Hannah Rogers Trust, could be compromised by the Core Strategy planning document for Newton Abbot.

Teignbridge District Council has paved the way for a "whole new town" to be built at Houghton Barton, which includes the former Seale-Hayne campus, by earmarking it for potential development.

The college was built 100 years ago, with a donation from Charles Seale-Hayne for an agricultural education institution. When it closed a decade ago, campaigners fought hard to stop the site being developed.

Yesterday, concerned residents met to discuss the planning framework, which is now in its final stages of consultation.

Former Seale-Hayne student Ray Bartlett said campaigners "breathed a sigh of relief" when Dame Hannah's and a local farmer moved in. A developer also owns part of the land. Mr Bartlett said the Core Strategy could have "devastating" consequences for both the charity and the farm.

Protesters fear Hannahs may even be driven out of the area altogether if it cannot expand as it wishes.

Bronwen Hewitt, chief executive of Hannahs, was not at the meeting, but said it was "imperative" that the planning framework was appropriate for both the public and the charity.

She said: "Clearly we expect the outcome to balance these needs. Our future intentions in relation to the site will depend on that."

Tony Murphy, of Seale-Hayne Area Residents' Endeavour (Share), set up to oppose the plans, said endangering the Hannahs expansion would be an " travesty". He told yesterday's meeting that he was "astonished" at the scale of potential development, and questioned Teignbridge District Council's estimate of 14,800 homes over the next 20 years. Mr Murphy cited the Office of National Statistic's prediction of 8,400 new homes needed.

But TDC chief executive Philip Vogel said the new lower migration figures were always expected. He said the estimates were based on a wide number of factors apart from migration, including trends such as children leaving home, births, marriages and divorces.

The council emphasised that any development would be subject to the planning process, and Mr Vogel said it was consulting with Hannahs and hoped the outcome would improve access and maintain farmland to the north.

Mr Vogel said: "None of us want to make mistakes and encourage unnecessary building." He said the council aimed instead to listen to local views and do everything possible to ensure Teignbridge had the homes, jobs and facilities it needs for a prosperous future.

But, in its formal response, Share wrote said it was "horrified" by the allocation of potential for 2,500 homes, calling it "nothing less than a scandal" on land left to encourage agricultural teaching.

Protesters say the Core Strategy "flies in the face" of planning permission granted for farmer Andrew Hayllor's farm shop. Mr Hayllor had hoped to include an educational facility which would teach clients at Hannah's about organic farming practices and food production. Bicton College has also recently reintroduced agricultural training on the site.

Yesterday's meeting was attended by a range of groups, including the Campaign for the Protection of Rural England, Transition Newton Abbot and residents who would be directly affected by the proposal.

The group accepted the need for a Core Strategy, to stop the current "free-for-all" after an earlier draft in 2007 was rejected by the Government. It means the council can easily be over-ruled by a planning inspector on appeal if no area is designated for housing.

Protesters also accept that some of the housing would have to go on the Seale-Hayne site, and had expected around 200, as specified when Plymouth University sold the land, while retaining a stake in any developments. But Brian Hall, of CPRE, warned that the current scale was "over development" of Newton Abbot, and said developers "would think all their Christmases had come at once".