Plans for a 480 home development on the outskirts of Helston have been dealt a massive blow by Cornwall Council officials.

The number of houses that can be built at the HX2 site near Clodgey Lane has more than halved following reassessment of an acoustic survey carried out in May, meaning other sites may need to be looked at if the town is to meet its target of up to 1,200 new homes by 2030.

In an email to Helston Town Council regarding the application, which is due to go to the Strategic Planning Committee on July 30, Cornwall Council's principal development officer Peter Bainbridge said: "It seems that agreement has been reached on the area of the application that could be affected by noise from Flambards. This has resulted in some 11 hectares not now available for development.

"It has therefore been agreed that the number of houses has been reduced to 219."

Mike Thomas, Helston's mayor, said: "If an area such as this is no longer able to deliver the number of houses , we will have to look elsewhere."

He said an application to build 340 homes at an HX1 site between Gwealdues and Trewennack, which was not supported by Helston Town Council and rejected by Cornwall Council, is currently going through appeal with the planning inspectorate, while the council "have had no information for the other extension area" HX3, near Nansloe.

He added: "One would imagine that's an area we would have to explore now."

The announcement was read out to councillors at a meeting of the town's planning committee on Thursday, shortly after the council had discussed the Cornwall Local Plan, the county's response to the government's National Planning Policy Framework which originally set the authority a target of 47,000 new homes by 2030, which has since risen to 55,000, and some councillors feel may rise again.

During the discussion Councillor Gillian Geer said the public needed to understand that the numbers were being imposed on councils across Cornwall by the government in London.

She said: "They don't perceive that this is something that everybody is having to do."

Councillor Thomas said the council needed to develop a strategic plan for the town "as a matter of urgency," to show preferred sites for development, while committee chairman Councillor John Martin said the council needed to find out "exactly how many homes we need."

Judith Haycock, Cornwall Councillor for Helston South, said the aim of 1,200 homes for Helston included houses that had been built or had planning approved since targets were introduced in 2012, and HX2 had been expected to make up the rest.

She said she was glad that the number had been reduced rather than trying to build the same number of houses on a smaller space, and added that it could be time to look again at HX3.

She said: "There are still other patches of land around Helston, so we could find more.

"There is still space near HX2, triangular pieces of green space.

"If HX2 gets permission then it could be there is enough room there at HX3 to make us up the 500 that's needed for Helston."