DRIVERS have been warned to expect tailbacks on approaches to the Forth Road Bridge this Sunday as engineers make preparations for a new survey of its suspension cables.
Traffic will be reduced to one lane in either direction between 3am and 11.30am so that bridge workers can hoist an inspection platform up to the top of the south tower.
Despite most of the work taking place in the small hours, the part-closure will hit thousands of weekend travellers, with “significant” queues expected.
The bridge’s chief engineer said he was advising drivers to plan journeys across the bridge for the afternoon.
Inspections will be carried out on suspension cables on the south tower following concerns about corrosion.
Sound equipment set up to detect the number of breaks in individual high-tension steel wires within the cables recently detected an increase in telltale “popping” noises.
Fears over the condition of the structure were central to the case for building a new bridge, the Queensferry Crossing, at a cost of £1.35 billion.
Bridgemaster Barry Colford said: “These restrictions are necessary for safety while steel beams are erected on the main cable high above the carriageway.
“These beams will allow us to winch an access platform into position so that we can open up the cable for inspection. The purpose of this inspection is to determine whether the recent increase in wire breaks that we have detected is indicative of a longer-term problem.
“It’s worth repeating that, while these breaks do merit further investigation, there are no immediate safety concerns and the cables still have more than enough strength to do their job.”
Sunday’s disruption will be repeated when engineers need to lower the inspection platform, but a spokesman said it could be in “weeks or months”.
Terry Airlie, secretary of the Queensferry and District Community Council, said that while he was glad the work wasn’t taking place on a weekday, any traffic near the bridge would affect local residents.
He said: “People try and find rat runs and shortcuts, which takes them through places like South Queensferry and Dalmeny. If there are ever engineering works or accidents, you find that very quickly the residential streets in and around the arterial routes get locked up with traffic.”