Norfolk County Council in the UK is calling a special meeting next month to discuss the funding gap ahead of work starting on Norwich’s Northern Distributor Road (NDR) by Balfour Beatty.
The NDR cost estimates have been based on 2013 prices, but this has now been increased by Â£29.9m due to construction cost inflation and unavoidable design changes.
With the project costs now totalling Â£178.45m, the council is planning to contribute Â£15m to cover half of the Â£29.9m shortfall and is seeking the UK Government to cover the remaining amount.
“This is a vital infrastructure project for Norwich and Norfolk.”
The increase in price is mainly due to delays as the central government reviewed all major infrastructure projects in the early years of the coalition government.
In order to secure development consent, higher and more costly standards are now required in the design of drainage systems, wildlife protection, landscaping and environmental measures and these include an additional Â£1m to be spent on bat barns and crossings.
Norfolk County Council leader councillor George Nobbs said: “This is a vital infrastructure project for Norwich and Norfolk.
“It brings real jobs and economic growth, with travel and transport improvement that will benefit thousands of people every day, and a Â£1bn-plus boost to the Norfolk and national economy.”
In June, Norfolk County Council secured development consent for a 20km dual carriageway to run from the A47 at Postwick to the A1067 Fakenham Road at Attlebridge.
The council has already submitted a request to the UK Department for Transport (DfT) for an additional contribution from national funds.
On top of Â£19m that has already been released for the Postwick Hub A47 junction improvement, the DfT has allocated Â£67.5m for the Postwick to A140 (Norwich Airport) stretch.