A further quarter of a million pounds has been earmarked for the Chester Farm project as the scheme continues to roll on.
However despite putting the money aside, the county council, which is bankrolling the lion’s share of the £11.1m heritage project in Irchester has said it expects not to have to use the funds.
The authority is in the midst of a financial crisis and is still looking for multi-million pound savings across its services to make a £65m shortfall before next April.
A financial report looked at by the Conservative cabinet this week (October 9) has earmarked the sum because “£262k of cost pressures have since been identified.”
The scheme, which is being constructed by the Shaylor Group, is running a year behind schedule.
A spokesman for Northamptonshire County Council said: “Chester Farm is a complex site which has involved specialist construction, and will bring to life thousands of years of Northamptonshire’s archaeology and heritage once completed.
“These figures are from a report detailing potential costs pressures, all of which are expected to be contained.
“The scheme has a dedicated project director and Capital Approvals Board are receiving a monthly progress update.”
The farm, which is in Irchester and situated just off the A45 between Wellingborough and Rushden, is of significant historical importance in the county according to historians.
The 17th century farmhouse is built on the site of a former Roman walled town and has evidence of Mesolithic, iron age and medieval periods.
When opened the project will become a major visitor attraction for the county and will feature a cafe, community, conference and training venue, offices and classrooms for school visits.
An archaeological resource centre in a huge newly built outbuilding has also been built and will house artefacts from the county.
Two months ago Cllr Michael Clark, who had the portfolio for finance, said the authority was proceeding with the scheme through gritted teeth but had to go ahead or it could be faced with paying back just under £4m pledged by the Heritage Lottery Fund.
The project was championed by former leader Jim Harker and in 2013 the authority agreed to pay £4.9m towards the scheme and find funders for the remaining £2.2m gap.
But it failed to find an agency to stump up the cash and had to pick up the bill.
A spokesman for Heritage Lottery Fund said the situation was still along the lines of the original agreement.
They said: “Where contractual obligations relating to an HLF grant cannot be met, the possible recovery of grant money is an option we consider as a matter of course.
“We are in regular contact with Northamptonshire County Council regarding the project and all matters relating to it.”