Restoration work to be carried out on Tay Rail Bridge

The central section of the modern Tay Bridge. Picture: TSPL

The firm said two workers had lost their footing because of the state of the timbers, but they had not been injured.

It has now applied to Dundee City Council and Fife Council to upgrade the walkway as the 1887 bridge is a listed structure.

The 50-yard-long stretch gives access to the bridge from a Network Rail depot at the Dundee end of the crossing.

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Network Rail town planner Pam Butler said: “The timber is rotten and maintenance staff have had accidents using the walkway.

“The timbers are dangerous and need to be replaced.

“We wish to upgrade the material used on the platform surface to one with a longer life, less affected by the prevailing elements.

“We would like to remove the weathered and rotten timber and provide a new timber or GRP [fibreglass] panel/boards for both sides.

“This area is not in general public use but is needed to allow maintenance and other staff access to the bridge and signalling cabinet.

“This area is only fleetingly visible to train passengers.”

Network Rail said the work was in addition to a major overhaul of the bridge which had been going on for more than a decade. This had included replacing walkway decking on the bridge itself.

Its spokesman said: “The wooden timbers are beginning to deteriorate and we are seeking to replace then with more modern decking.

“There have been a couple of incidents where staff members have lost their footing due to the condition of the timbers and, while no injuries have been caused, they are no longer fit for purpose.

“We remain on-course to complete the £80m refurbishment of the bridge in 2017.

“Replacement of the timber access walkway is a very minor element of the programme.”

A spokesman for Dundee City Council said: “An application has been submitted which will be considered in due course.”

A painter was killed when he fell on the bridge four years ago - its first recorded death - but a medical condition is thought to have been a factor.

David Rodger, 44, from Cowdenbeath in Fife, fell 6ft on to a ledge beneath the bridge.

He worked for the Coventry-based ThyssenKrupp Palmers, one of several firms repainting the bridge for Network Rail.

David Simpson, Network Rail’s then route director for Scotland, said at the time: “Such events have become extremely rare in the last decade as a result of rigorous safety regimes” on the bridge.

The firm said there had been no previous recorded deaths on the bridge.

The two-mile-long crossing replaced the adjacent original bridge, whose half-mile centre section collapsed in a storm in 1879.

All 59 people aboard a Dundee-bound train were killed in the disaster after it crashed into the Tay.

It led to major changes in bridge construction, with the official inquiry concluding that the bridge had been “badly designed, badly constructed and badly maintained”.

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