Interviews

Easing the bottleneck

Mark Langman, Network Rail route managing director for Wales, spoke to RTM about the recent Loughor Viaduct replacement and track redoubling in south west Wales.

Good timetabling can only take services up to a certain rate; eventually track works are necessary to free up bottlenecks and increase capacity on the railway. RTM spoke to Network Rail’s route managing director for Wales, Mark Langman, about the newlycompleted £48m South Wales upgrade to replace Loughor Viaduct and redouble a 5.25- mile stretch of track at Gowerton.

Jointly funded by Network Rail and the South West Wales Integrated Transport Consortium (SWWITCH), the Loughor Viaduct replacement was carried out by Carillion and the redoubling was undertaken by a Colas Rail/Morgan Sindall joint venture. The line reopened on April 8.

Langman said: “It’s a huge amount of work done over a 16-day closure: to remove the old viaduct, put in a new one and redouble fi ve and a half miles of track, build a new platform, a new footbridge, put in new signalling. And we managed to open it on time on Monday morning.”

Preparatory work included the installation of a new footbridge at Gowerton station towards the end of January and the upgrade of Duffryn level crossing to accommodate the additional line. Works at the station will also provide new lighting, signage and CCTV.

Doubling the line

The Gowerton redoubling “completely alleviates” a critical bottleneck in South Wales, removing “pretty much the last single line of track between London all the way through to Carmarthen,” as Langman put it.

The single line was constraining services, with the line at maximum capacity and even limiting the number of stations services could stop at.

“We couldn’t run any more trains on there if we wanted to. In fact the space we had was so tight that at one station, Gowerton, we couldn’t actually stop trains because it would take too long. Effectively you would have trains waiting either side to go through it. It does absolutely transform that railway.”

Arriva Trains Wales has announced in its timetable changes that from May 14 more trains will be calling at Gowerton in each direction, which Langman described as “fairly amazing”.

A new ‘Swanline’ commuter service will also run from Cardiff to Swansea, and all single car trains on the Swansea – Cardiff – Pembroke route will be replaced by two-car trains, effectively doubling capacity.

Exploiting the infrastructure

To make the most of the infrastructure in place, it was essential to carefully plan services before investing in upgrades such as the redoubling project. In this case, Langman said, there was simply no other option.

“This redoubling was a great example of where you’ve absolutely exploited the infrastructure that you’ve got and you’ve timetabled it to the max. The only other solution when you get to that situation is to do something to the infrastructure itself. In this instance, it was to redouble it.

“Where you’ve got similar sections of single line elsewhere in the country, I’m sure similar challenges could be faced. Certainly exploiting the timetable before you get to those options is the right thing to do. You’ve got to be cost effective but there really was no alternative in the position we found ourselves in down at Loughor and Gowerton.”

Intensive closures

Conducting intensive rail upgrades always presents the issue of balancing passenger disruption with the need to close the railway. Network Rail chose to close the line for a 16-day block, which it concluded was the least disruptive option.

Langman said the alternative would be to have a four-day closure at the start of January every weekend up until Easter and then the four days over Easter to complete the work.

“In the end we plumped for doing as much of the work as we could alongside the open railway throughout that period, and then closing it for 16 days and doing everything at once. We thought overall that was least disruptive, rather than closing it over a period of two or three months. You have to weigh up the options against putting passengers on buses.”

There was a diversionary route available, which allowed passengers to stay on trains for as long as possible. Services were diverted between Llanelli and Neath and only local journeys had to be replaced by buses during the closure.

Loughor Viaduct replacement

The biggest challenges included the bridge replacement, and its location in a protected area, Langman said. The Loughor Viaduct was constructed on site, and the 220m structure was propelled over the river on temporary piers alongside the existing bridge.

Once the railway closed, the old bridge was demolished and the new bridge, with the track on it, was slid sideways into place. This was achieved within 8mm of precision, which was “pretty amazing”.

He explained: “The propelling was done while the railway was running beside it. We did as much as possible keeping trains running, and only at the very last minute when we had to slide the new bridge into position, for obvious reasons, we had to close the railway. That was quite tricky but we did it.”

The Loughor estuary is a SSSI (Site of Special Scientific Interest, protected by Natural England), with associated marine conservation orders, and a very high tidal range. Being so exposed to the weather was also challenging to the project.

Langman added: “We’ve been on site since the beginning of last summer getting all of this ready and doing preparatory work, so a lot of this was in place ready to go.”

Welsh investment

Campaigners have argued that the railways in Wales suffer from under-investment, with many routes and stations left untouched while urban English areas win the bigger infrastructure projects.

But Langman said this was “just the start” of greater investment in Wales, and highlighted upcoming work to improve the railway across the country. “We’ve recently announced a huge investment package for CP5 for Wales, totalling nearly £1bn expenditure and this is one of the first steps towards that, alongside other works we’re doing to improve capacity around Cardiff.

“We have the prospect now of looking forward to electrification on the Great Western Main Line and of the Valley Lines network. This is just the start of the journey of investment for Wales and it’s really great news.”

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