ENGINEERS ARE to open up sections of the Severn Bridge's twin suspension cables to check for cable corrosion, it was revealed this week.
The £3M Highways Agency investigation, scheduled to take place after the Easter break, will include installation of acoustic monitoring to check for any wire breakage in the 511mm diameter cables.
The move comes after broken wires and corrosion were found in Scotland's Forth Road Bridge in 2004 (NCE 6 January 2005).
The 40 year old Severn Bridge is just two years younger than the Forth and its cables were spun from the same diameter wires.
But while the Forth has suffered from high traffic loads, exacerbating the problem of already weakened cables, traffic on the Severn today is relatively low.
It currently carries half the load it was designed for, as more traffic opts to use the nearby Second Severn Crossing.
'We're hopeful of getting favourable results, but the environment here is different to the Forth. Here it's much wetter, ' said Highways Agency senior bridge engineer Martin Lynch.
Consultant Faber Maunsell and contractor C Spencer will carry out the inspection - the same team that worked on the Forth Road Bridge cable inspections.
Examination of the Severn Bridge cables will be carried out between May and September at seven locations. If corrosion is found a £20M dehumidification system will be installed.