Restoration work on historic Barmouth Viaduct set to be completed by next autumn

A £30 million restoration project on the historic Barmouth Viaduct is expected to be completed by autumn next year.

Work on the bridge got underway two years ago after engineers confirmed the structure was rotting from the inside out.

The Grade II* listed single-track wooden bridge was built by the Aberystwyth & Welsh Coast Railway in the 1860s and crosses the Afon Mawddach estuary near Barmouth.

At 820 metres, it is the longest timber viaduct in Wales and one of the oldest in regular use in Britain and is one of just nine timber bridges maintained by Network Rail.

The viaduct was converted into a swing bridge in the early 1900s but the mechanism has not been functional since it was closed in the 1980s.

The swing span and mechanical equipment are being retained as part of the restoration project but purely for aesthetic reason as part of an agreement with Cadw.

Due to the structure’s listing, Network Rail and its main contractor Alun Griffiths are attempting to maintain the viaduct’s appearance by replacing the timber and metallic elements on a like-for-like basis.

Other elements are also being retained or added for heritage reasons. These include hundreds of “fake rivets” that have been added to the structure to match the bridge’s “original identity”.

Aesthetic

Network Rail project manager Gareth Yates told New Civil Engineer, “The rivets don’t do anything,” adding. “They are purely aesthetic, but their retainment is part of the requirements of the job and rightly so, in my opinion.

“The bridge is steeped in history, and we are proud to be maintaining that history.”

During the first two phases work has focused largely on replacing and repairing the decayed timber elements of the bridge.

All main rail supporting timber has also been replaced as has the walkway decking.

The final phase of work focuses on restoring the metal elements of the bridge.

It was originally planned to take place in one go this autumn, but the job has now been split across the next years to reduce the impact on rail services and tourism.

“Tourism is a massive part of the economy in this part of the world, so we agreed not to work during the summer months,” Yates said.

“The downside is we’ve had to work through some pretty horrendous conditions. There have been times where we’ve had rain going sidewards and 96km/h winds battering us from all angles – there have been days where we’ve not allowed anyone to go out on to the bridge as the conditions were simply not safe.”

“At the time, when you’re working out in the cold and rain it’s not very enjoyable. But looking back now it is a huge honour to work on such an iconic structure – it’s the kind of thing some engineers wait their whole life for.”

Once completed the work is expected to safeguard the structure for up to 60 years with Network Rail expecting it to be another 20 years before any major maintenance is needed.