The landmark Blackhall Place Bridge, designed by one of the world's leading bridge architects, Dr Santiago Calatrava, will cost more than expected after running into construction difficulties.
The futuristic-looking 44-metre bridge, a key aspect of Dublin City Council's traffic-management plans, was to have opened this spring at a cost of about €6.25 million. Some estimates in trade publications are now as high as €20 million.
However, the City Council insisted this week that the construction problems had now been solved, and the city engineer, Mr Michael Phillips, said that the council would be "doing its utmost" to keep the cost overrun to within 25 per cent of the original tendering price, which he described as normal.
Dr Calatrava, a Spanish architect and engineer, has designed many elaborate bridges throughout the world, probably the most spectacular of which crosses the Guadalquivir in Seville.
The Blackhall Place bridge is of a striking design and incorporates a pair of tied bow-arches from which the deck structure is suspended by high-tensile steel hangers. The arches and the balustrades of the pedestrian walkways curve outwards towards the river.
The curve of the balustrade produces a pedestrian walkway, which varies in width from three metres at the quays up to about seven metres at mid-span. The main body of the balustrades is to be toughened glass. The pavement of the walkway is to be laid in granite flags with translucent glass panels. The bridge is likely to become a prominent city feature at road and rail routes to the south and west. It will be visible from both Heuston Station and the Civic Offices.
Dr Calatrava has also been asked by the City Council to design another Liffey bridge on the eastern side of the city to link Macken and Guildhall streets. The two new bridges are aimed at taking the burden of north-south traffic away from O'Connell Street.
The four-lane Blackhall Place bridge, linking Ellis Quay to Usher's Island, is intended to carry up to 2,000 cars an hour and aims to distribute north-south city-centre traffic more efficiently.
According to Mr Phillips, the widely varying estimates of the final cost of the project are a result of negotiations with the contractors over prices for unforeseen works and changes to the initial designs.
While reports in construction industry trade publications said that these could increase the final price by as much as €15 million, Mr Phillips said that final positions had yet to be taken and much negotiation remained.
Engineering difficulties with the project related to foundation details which were not identified by the original study and the supply of steel from Germany, as well as with changes to the requirements for welding the steel together, he said.
The bridge was welded together at Harland and Wolff in Belfast. A spokesman for that company told The Irish Times that changes had been required, but he added: "Harland and Wolff has done everything that it was asked and our work is complete."