Borough Viaduct

The key to unlocking London Bridge’s western bottleneck

Doubling the tracks

A new viaduct built over Borough Market as part of the Thameslink Programme has doubled the number of tracks heading west out of London Bridge station. The Borough Viaduct, which runs alongside the existing rail bridge above the market, was completed in 2011. It was then brought into use in January 2016.

The new two track viaduct doubles the number of tracks going west from London Bridge station, increasing the number of trains that can travel through the station to Charing Cross, Blackfriars and beyond, reducing delays for passengers and unlocking a historic bottleneck. This means Southeastern services for Charing Cross and Thameslink services each have their own dedicated lines now. Previously, these services had to share lines and platforms, reducing the space available for Thameslink trains.

As part of the project, completely new tracks and signalling equipment have been installed across both the new and existing viaducts, improving performance through this junction.

A new landmark for London

The new viaduct spans over 500 metres, from the end of platforms 8 and 9 at London Bridge station, through Borough Market and on to Metropolitan Junction, where the railway crosses Southwark Street. The most visible part of the viaduct, the part which spans Borough High Street, was constructed ‘in situ’, on top of the new viaduct.

Working with Borough Market

Despite the majority of the construction taking place within Borough Market itself, the market traded as usual throughout the work. Some pitches were moved to a purpose-built trading space within the existing market footprint, and were moved back to the main market hall when work was completed.

Minimising the effects of construction on local residents and businesses was a key goal for the project. Other measures taken by the project to minimise our impact include building an acoustic screen to protect Southwark Cathedral from noise pollution, ensuring the construction was completed in time for the Olympics to allow Borough Market to fully benefit from the influx of visitors and ensuring no noisy work took place during the market’s busiest hours.

Keeping the market operational throughout the work introduced additional construction challenges, but was essential to help maintain the viability of the market. A temporary market roof was constructed in Jubilee Market early on to provide a space for traders displaced by the work.

Respecting the heritage

The central challenge for the project was to create a rail network that is fit for the future, while retaining the rich character of the local communities. The work at Borough took place in a busy urban area which is also of significant historic interest. The viaduct design has preserved as much of the local heritage as possible, with the viaduct weaving its way through the historic market area, preserving as many buildings as possible.

Although some demolitions were necessary, key landmarks like the listed Globe pub and the Wheatsheaf remain in place. Although the Wheatsheaf had to have its top floor removed to allow the viaduct to pass overhead, a new basement and ground floor extension have allowed it to continue to thrive as a popular pub. Meanwhile, the cast-iron Victorian market roof was taken off site to be refurbished before being reinstalled when the viaduct was complete, helping to preserve the history of the area.

New buildings, new discoveries

Several new buildings have been constructed in the spaces created by the demolition. On Bedale Street a new retail and office building has been built, as well as a new entrance to the market. On the site of what was once 16-26 Borough High Street, a new glazed market hall was built to bring Borough Market back to Borough High Street for the first time in centuries.

Across the road at 11-15 Borough High Street, a new retail/office building has been built. This building is set back from the highway, providing additional circulation space for pedestrians and opening up views of the listed post office building.

Archaeological work during construction of the new Borough Viaduct uncovered a wealth of remains from the Roman, Saxon, medieval and more recent periods that provide a fascinating insight into the formation and growth of the settlement in the Southwark area. Finds included a previously unknown Roman bathhouse, which featured a rudimentary underfloor heating system, under what is now 11-15 Borough High Street. This is now a scheduled ancient monument and important evidence for the significance of the Roman activity on the south side of the river.

Other stand out finds included evidence for the Boudican revolt, substantial evidence for the Saxon/medieval defences of the settlement and the St. Saviour’s/Park Street burial ground.

Below you can watch the full timelapse of the Borough Viaduct installation

The 1200 tonne, 72m bridge structure was slid into place over a long weekend in Spring 2011 – the weekend of the Duke and Duchess of Cambridge’s royal wedding – at an average speed of 3m per hour.

Constructing the viaduct in this way minimised disruption and road closures during the installation and helped to keep road and rail traffic moving during the work. The white, tubular bow truss now forms a striking new gateway to the City of London.

You can read the 2017 Western Approaches Viaduct CEEQUAL submission here.

Related Case Studies

Built Heritage: Borough Viaduct

The case study examines how heritage was protected and conserved during the construction of the Borough Viaduct and Borough High Street Bridge.

CEEQUAL: Borough Viaduct

This CEEQUAL case study evaluates how the Borough Viaduct project reduced the impact to neighbours and preserved the historic environment.

Delivery & Execution Strategy: Key Output 2

How collaboration and incentivisation were crucial to successful delivery of Key Output 2, including the re-signalling, track remodelling and construction of London Bridge station, construction of the Bermondsey Dive Under to the east and Borough Viaduct to the west.