A consultancy firm appointed to advise on the long-delayed A5 road project has been paid over £51m, it has emerged.
The Executive first committed to the dualling of the road between Aughnacloy in Co Tyrone and Londonderry in 2007.
But the project has faced repeated funding problems and legal challenges.
Last year Infrastructure Minister Nichola Mallon pledged that she would ensure the scheme was funded.
Information provided by the Department for Infrastructure shows total costs of £82.5m by last October, accumulated over the last 13 years. The biggest chunk — almost 63% — has gone to engineering services consultancy WSP, formerly Mouchel.
At £51.6m in total, it has earned nearly £4m a year over the term of the project.
According to the international firm’s website, its transport and infrastructure section offers a “holistic approach to transport and infrastructure planning, design and management”.
The Department for Infrastructure defended the £51.6m paid to WSP since 2007 for “design and development work”.
A spokeswoman said: “As is the case with all major works projects, significant costs need to be incurred before works commence on the ground.
“This typically includes scheme planning, design and development and in the case of the A5, there have been considerable additional costs associated with this phase of the project due to the need to hold further public inquiries and defend a number of legal challenges.
“Given the overall scale of the project and the challenges it has faced, the costs incurred to date are considered proportionate, with the Department’s consultants being paid to reflect their significant input throughout the various stages.”
She said the business case for the project demonstrated “a solid return for investment”.
The department said the new dual carriageway would “reduce journey times and improve road safety, while balancing regional infrastructure, improving competitiveness and economic prosperity through improving connectivity and accessibility across the region.”
WSP referred queries as to whether its charges represented value for money to DfI.
The scheme to transform the road between Aughnacloy to Londonderry into a dual carriageway would be the single largest road scheme here, and part of a major cross-border road project to improve links between Dublin and Derry.
The scheme has been estimated to cost £650m to £850m. But it faced a major funding setback in November 2011, when the Irish government withdraw most of its £400m funding. However, £75m was later recommitted by the Irish government after the Fresh Start Agreement.
In October last year, the Dublin government pledged €500m towards cross-border infrastructure projects such as the A5.
In the information provided by the DfI, it said the Department of Finance had received £8m in 2009/10 and £14m in 2011/12 financial year from the Republic.
Legal challenges have also beset the project, with a decision to proceed quashed by the High Court in April 2013 after a bid from landowners and businesspeople.
Then construction was due to start on a stretch of the road from Newbuildings to Strabane but had to be put on hold after another legal challenge from the same quarter.
Alliance MLA Andrew Muir, a member of Stormont’s Infrastructure committee, said: “Expenditure of this colossal level is a matter of real concern.
“Whilst investment in design and development work essential to enable this vitally important project to proceed is entirely justified, the additional cost arising as a result of legal challenges mounted proves yet again why we need to review and improve the planning and approval process for major capital projects.
“Every penny spent as a result of these challenges is less money for other vital projects, our health service, schools and other essential public services.”