A £500,000 revamp of a creaking Oxford community centre may have to be abandoned after the city council found it was built on a former quarry.

Bullingdon Community Centre, in Peat Moors, Headington, was set to benefit from the major makeover this month – but it has been thrown into uncertainty.

A representative of the community association which looks after the centre said it was ‘very angry’ at the delay and ‘poor communication’ from council officers.

The centre, built in the late 1940s, has been operating for more than 40 years beyond its expected lifespan and is now the only community centre serving Lye Valley and Wood Farm.

Tim Sadler, executive director of ‘sustainable city’ for the city council, said: “During recent ground condition surveys necessary to finalise the design, surveyors have discovered that the site sits on an old quarry.

“This materially changes the building requirements and significantly increases the likely costs of the project.

“Therefore, the city council has immediately commissioned an analysis of design options and costings for works including considering other potential sites not subject to the same engineering complexities as building on landfill.”

Mr Sadler said the problems had been ‘unforeseen’ and that the council had talked to the Bullingdon Community Association about the delays.

Further work is expected to take up to six to eight weeks and add hundreds of thousands of pounds onto the project’s price tag.

Community association secretary Richard Bryant said it had been ‘taken by surprise’ over the delays – after it had moved 12 of the centre’s 14 groups out.

He said: “We were caught completely on the hop: all of the group is extremely angry. We feel the contact from the city council has been very poor and we should have been informed that there were possible issues many months ago so we didn’t go to the bother of virtually closing the community centre.

“It is a mess as far as we’re concerned. We want the work to go ahead.”

He said it should not have been unexpected that the centre could have been built on a quarry because of previous mining in Headington.

In July 2017, groups using the community centre were left in the lurch after the city council closed it over safety concerns. But the next month, the authority installed nine props to the building and it reopened.

Lye Valley councillor Pat Kennedy said: “It’s an important community asset and it serves Lye Valley and Churchill wards. There are pockets of deprivation in both.”