18.01.16
Unexpected damage keeps WCML viaduct shut until March
The battered Lamington Viaduct, about 10 miles south of Carstairs on the West Coast Main Line, will not open until early March after suffering further damage as a result of continued bad weather, Network Rail has said.
Initially expected to reopen in January after it was severely damaged by Storm Frank on New Year’s Eve, ScotRail Alliance confirmed today that engineers will only be able to reopen the viaduct nearly two months from now.
They have been working to divert the Clyde (using over 1,500t of stone to dam part of the river) and stabilise the structure after the important viaduct’s second pier nearly collapsed as floodwater destroyed much of its foundations.
Engineers were able to stabilise the pier last week by pumping more than 300m³ of fast-setting concrete into the void, after which they conducted structural checks on sections of the viaduct that were previously too unsafe to inspect.
But the latest inspection showed that persistently bad weather and high water levels caused more structural damage to another pier on the viaduct, with three steel bearings, which support the bridge deck, left battered.
The damage to the viaduct’s foundation is also worse than previously thought, meaning Network Rail will need more time and significantly more work to stabilise the structure once again.
Phil Verster, managing director of ScotRail Alliance and spokesperson for much of the post-flood works, said Storm Frank’s damage has been “very serious”, leaving engineers in a “race against time” to stabilise the structure before it collapsed into the Clyde.
“Only now that we have won that race can we really see the full extent of the damage,” he added. “The damage from the floodwaters is significant. We have had to use hundreds of tons of rock to divert and reduce the flow rates at the piers and an extraordinary amount of concrete just to stabilise the second pier.
“Unfortunately the scale of the damage and the complex nature of the engineering challenges means that the repair is going to take longer than we initially thought.”
All TOCs operating services on the WCML are cooperating to ensure passengers and freight can keep moving, with temporarily timetables and arrangements secured for the time being.
Virgin Trains’ executive director for operations and projects, Phil Bearpark, said this will mean the operator’s journeys will take an hour longer than normal in some routes, although Glasgow-Carlisle trips can be replaced done in a replacement train.
Over the coming weeks, engineers will be installing extra concrete supports on either side of the damaged second pier to strengthen the viaduct’s structure before installing more 8m-long rock anchors and mini piles through the foundations, thus supporting it from a “much wider and lower base”.
The third pier will also undergo structural repairs and the course of the river will be widened to reduce future water pressure on the viaduct, all before the steel bearings are replaced, the viaduct bridge-deck realigned and the track re-laid.