CONSTRUCTION OF a new Forth Estuary crossing could start in as little as seven years' time after the Scottish Executive approved replacement of a new road bridge last Wednesday.
Suspension cables on the existing Forth road bridge are suffering from advanced corrosion (NCE 8 December 2005).
The structure has lost an estimated 8 to 10% of its original strength.
The bridge's operator, the Forth Estuary Transport Authority, is to start installation of dehumidi ation to arrest corrosion later this year.
But if corrosion cannot be halted, the bridge is expected to fall below its minimum safety margin of 2.0 in 2013-2014.
Scottish transport minister Tavish Scott told ministers that a £1bn-plus replacement crossing is required. He said three possible locations have already been identifid, though further work is required to determine whether a bridge or a tunnel is the best option.
Scottish Executive ministers have asked Transport Scotland to work up more detailed plans for the replacement 'multimodal' crossing.
Scott said the Executive was seeking a nal recommendation of what type of crossing is required, the location of the crossing, and the costs involved by 31 May.