Some of Britain's biggest house builders are waiting to swoop on the district's green belt as barristers prepare for a major public inquiry which starts tomorrow.

More than 100 green sites treasured by the public will be under unprecedented challenge at the six-month-long hearing which will cost Bradford Council more than £1 million.

Inspectors will deal with about 7,000 objections to the Council's proposed replacement Unitary Development Plan and 700 different issues. The vast majority of cases are about using fields for housing.

The sites which developers and owners are targeting are scattered across the district and many are small.

About 1,500 objections have been submitted by residents to the Council's proposal to keep Sty Lane, Micklethwaite, earmarked for housing with development delayed until 2009.

The residents, who have formed Greenhill Action Group, want it designated as green belt to protect it from any development while developers say the restriction on the start date for building the homes should be lifted.

The action group says it could result in 800 homes and have raised thousands of pounds to engage professional representation at the inquiry.

Other main sites under threat, which the Council wants to retain as green belt, are at: Bradford Road, Menston; Addingham - near the railway line and village; Daisy Hill Farm, Keighley; Moor Road, Cottingley; Glenview Road, Nab Wood; Brampton Farm, Simpson Green, Apperley Bridge; Brook Lane, Clayton/Clayton Heights.

The UDP battle, which will unfold at Victoria Hall, Saltaire, over the next six months, will be keenly watched by companies like Alfred McAlpine developments, John Ogden Properties, Taywood Homes and Bryant Homes, all waiting for sites to become available.

The Council insists there is no need to release any green belt for housing because needs can be met from other empty sites.

But challenges are expected on the Council's estimate of housing needs and the ability to accommodate it through using former industrial land.

The proposals for the "green" UDP, the Council's planning blueprint, were drawn up after a huge public consultation exercise. It allocates land use across the district for the next 15 years.

The document will act as the yardstick for every planning application received for developments in Britain's fourth biggest metropolitan district.

The Council has tried to protect some green sites previously allocated for housing - but as yet undeveloped - by imposing stipulations preventing them from being built on for several years. Some of those restrictions are also being challenged by objectors who want houses built sooner.

The evidence will be considered by four Government-appointed inspectors but it is likely to be the beginning of next year before they release their recommendations.

A large number of people have put in written submissions but there are still many to be heard at court-room-type sessions with cross examination by lawyers.

The Council's executive member for the environment, Councillor Anne Hawkesworth, said: "We are in an unprecedented situation because of the challenge from this large number of owners but we feel it is vitally important to keep the green belt for the people of the district.

"We consider our figures add up and we are releasing ample brownfield (former industrial) sites for residential use. The thrust of our plan is regeneration and developing housing in the city and town centres."

Baildon residents are supporting Bradford Council's proposal to keep Jenny Lane playing fields as recreation land even though it is designated for housing in the existing plan. But its owner, the Roman Catholic Diocese of Leeds, is objecting and says it should be kept for housing.

Campaigner Julia Donaghue said they had prepared a full dossier of the history of the site and given it to the Council to support its submission. She added there was an excellent case to prevent housing.

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