Docklands Light Railway Extensions, London, United Kingdom

Since opening in 1987, the Docklands Light Railway (DLR) has been central to the regeneration of East London. The system started with three 'arms', running running to termini at Stratford (north), Island Gardens (south) and Tower Gateway (west), intersecting at Poplar. It has been a key facilitator of residential renewal in the area and of the creation of the Docklands business and finance district. Its next leading role is as a key component for the UK's staging of the 2012 Olympic Games.

THE PROJECT

The original 13km, 13 stations system cost £77m, but in the following 20 years over £1bn has been spent on upgrades and extensions. The most prominent are to Bank (July 1991), Beckton (March 1994), under the Thames to Greenwich and Lewisham (November 1999) and to London City Airport (December 2005).

The Olympic Games in London in 2012 provides the opportunity to re-align rail services. The DLR will take over the North London Line from Network Rail on the now abandoned section between Stratford and Canning Town. This received Government approval in November 2006 and will allow easy access to the Olympic Park and other locations in London.

To be renamed Stratford Regional, the current mainline station will have two DLR stations. The original high-level single platform was replaced in June 2007, with the extension to feature a new station at low level.

In May 2006 Transport for London (TfL) awarded a new £400m franchise to operate and maintain the DLR system to Serco Docklands (part of the Serco Group), reflecting improvements made during the nine years of its previous franchise begun in 1997. DLR infrastructure is in the control of CGL Rail on a 24.5-year licence.

The new franchise brings targets, including at least 96% of trains running within three minutes of schedule, completion of the Woolwich Arsenal and Stratford International extensions, and the three-car upgrade to increase capacity between Bank and Lewisham.

INFRASTRUCTURE

Because of the nature of the territory it traverses, a mix including existing intensive land use and the large bodies of water that were former East London docks, much of the DLR is on viaduct, with many high-level stations. The main depot is at Poplar, and like the second at Beckton, has been subject to extension to handle more and longer trains.

The prospect of the current 60 million ridership by 2025 has dictated lengthening of platforms to take trains strengthened from two to three cars. Wholesale extensions of viaducts and realignment of curves take place, also the relocation of South Quay station. In May 2007, Taylor Woodrow was awarded a £200m contract for the construction works in connection with the train-lengthening project.

The line to Bank terminus in the City, an afterthought western extension of the DLR, supplementing the initial Tower Gateway terminus, is in tunnel. Likewise, part of the Lewisham line is in bored tunnel, with a cut and cover section (1.7km) at near ground level.

King George V is the temporary terminus of the branch from Canning Town opened in 2005 to serve London City Airport and, by early 2009, Woolwich Arsenal.

Breakthrough on the second of the new twin-bore tunnels under the Thames took place in July 2007. Like Lewisham, Woolwich DLR will be an interchange with main line railways.

In July 2007, a £67m main construction contract was awarded to a Skanska-GrantRail joint venture for the £238m Canning Town-Stratford International line. The project includes rebuilding stations at Stratford, West Ham, Canning Town and Royal Victoria to DLR specification with step-free access.

New stations will be built at Star Lane, Abbey Road, Stratford High Street and Stratford International, the last adjoining High Speed 1 and serving the Olympic Park. In addition, a new station at Langdon Park on the original line from Stratford is due to open in 2008.

ROLLING STOCK

Newer technologies such as monorails, guided buses and rubber-tyred trains were rejected in favour of a conventional steel wheel on rail system. After sale of the initial fleet to Essen, services are operated by 94 automated vehicles built by BN Construction/Bombardier.

A further 55 cars were ordered between 2004–2006 for the City Airport and Woolwich line, creating extra capacity for the 2012 Olympic Games and the Stratford International extension. Maximum operating speed is 80km/h (50mph).

Due for delivery from 2008, they are being built at Bombardier's Bautzen plant in Germany, with electrical equipment supplied by the company’s Mannheim factory and bogies from Siegen.

SIGNALLING / COMMUNICATIONS

Automatic train control is managed from the central control room at Poplar using a 'moving block' system which allows for closer headways than a conventional fixed block system. It is based on the Seltrac system, developed by Alcatel of Canada.

The train's on-board computer continually communicates with the central computer, and if this signal is broken a train will be stopped until authorisation is given for it to continue. A train can still be driven manually, but if the driver over-speeds or leaves a station when the route is not set, emergency brakes will be automatically applied. In the event of a complete signalling failure, trains can run in emergency mode at 20km/h (12mph).

THE FUTURE

The completion target for the Canning Town-Stratford International line is mid 2010. During 2012, the line will be the principal link between games venues at the Olympic Park and the Excel Arena that adjoins Custom House DLR station. The extension to three-car operation will be completed in time for the Games, creating a 50% capacity increase on the system.

A four-station Dagenham Dock extension from a new junction at Gallion's Reach is projected to begin construction in 2011 for operation by 2016. The growing complexity of the system may call for routes to receive simple distinguishing designations as per TfL Underground. Given the runaway success of DLR, prospects for long-term expansion of the system appear good.

Click here for printable version