FEARS have been raised that the final bill to move thousands of metres of utility cables for the Capital's tram project could be set to soar by millions of pounds.
Figures set to be presented to the city's tram sub-committee next week show that contractor Carillion moved 40,000 metres of pipes and ducts when it was originally due to be paid 40 million to divert just 27,000m.
It is understood that the Wolverhampton-based firm is seeking an extra 10m for the work, with the final bill yet to be settled.
A council report notes that agreement on the final account "remains outstanding," however, it is hoped that utility firms will help pick up the bill.
Carillion ended its association with the tram project late last year when tram bosses said around 80 per cent of the utility work had been completed.
Since then, Northern Irish firm Farrans and Middlesex-based Clancy Docwra have been drafted in to complete the outstanding work at Haymarket, Picardy Place, Edinburgh Airport and Ocean Terminal.
According to tram firm TIE, a total of 46,575m of utilities have now been diverted – 97 per cent of the total – with all work on the first phase due for completion by September.
However, the company behind the tram project has refused to reveal details of how much the contracts with Farrans and Clancy Docwra are worth, claiming that to do so would undermine the project.
It is the lengthy delays to this work which have led to the contract dispute with Bilfinger Berger, with the German firm arguing it cannot carry out construction work until the utilities are diverted.
It is understood that the contract drawn up between TIE and the construction consortium promised Bilfinger would have "exclusive licence", meaning the streets would be clear of other works.
Long-time tram critic John Carson, a former director of maintenance for Network Rail, said a final bill in the tens of millions would be a "conservative estimate" for the extra work carried out by Carillion as well as the contracts with the other two firms.
According to the council, the amount of utilities work carried out has led to a "significant" improvement in the quality of the city's infrastructure and should help provide faster broadband internet.
It is also likely that utility companies will contribute "several million pounds" to the cost of the work, the council said.
A spokeswoman from Edinburgh Trams said: "We are currently agreeing the final account for the works completed by Carillion.
"This is part of the normal process associated with closure of a contract of this nature."
Carillion did not respond to a request for comment.