AusRAIL, Market Sectors

Crossrail: the operational challenge

This special 2-Part Series examines the many and significant operational challenges that Europe’s largest rail project, Crossrail, presents.

By Clive Kessel

Much has already been written about Crossrail and many more articles will appear in the years to come.

The engineering issues have been to the forefront of information to date, detailing the civil works, the tunnelling, the signalling and the communications systems.

Very little has appeared on the considerable operating challenges that this cross-London link will present but since the whole purpose of the project is to transport masses of people, it is vital that all facets of operations are considered.

The engineering should be designed to fulfil the operating requirements and if these are not properly specified at the outset, it will be nigh impossible to change the engineering in later years.

A fascinating insight into this challenge was given at an Institute of Engineering and Technology (IET) evening lecture by Charles Devereux, Crossrail’s head of railway operations.

Charles has a long pedigree in this field – both from BR days and the privatised railway – and it was evident that his experience will prove invaluable to the project.

Technical overview
The idea of Crossrail has been around since the late 1980s and the basic concept of a fast east-west railway across London has remained unchanged over the intervening period.

Such are the vagaries of UK planning processes and the need to navigate complex parliamentary procedures, Crossrail spent three and a half years in Parliament from 2005, with funding arrangements put in place about six months after royal assent. Not until 2009 could any physical work be started.

Various terminating points for the train service were considered during development but the ones eventually selected were Maidenhead and Heathrow in the west, Shenfield in the east and Abbey Wood in the south-east.

Core to the project is 21km of new tunnel, with seven new sub-surface stations (Woolwich could yet make eight) and 28 stations on 90km of existing lines over which Crossrail trains will run.

The central alignment is the only practical route through the myriad of tunnels and pipes that already exist in subterranean London.

Seven tunnel boring machines will be used, each 120m in length construction will continue until 2018. Crossrail will have 146km of electrified railway all at 25kV, 61 platform extensions are needed and at least two new signalling interlockings.

Communications-Based Train Control (CBTC), as yet unspecified, will be required for the central section but visits to Paris and other major cities are being made to determine the best option.

Traction power feeds will be located at Pudding Mill Lane near Stratford and Kensal Green. Should one fail, the other will be capable of feeding the entire central section

Journey time reductions are part of the package with Paddington to Liverpool Street coming down to around ten minutes, bringing much needed relief to the Central, Circle and Hammersmith &amp City lines.

Rolling stock plans are still being refined but the broad order intention is to have ten-car trains that are around 15% lighter than current offerings, each to be 200 metres in length capable of carrying 1,500 seated/standing passengers and incorporating regenerative braking.

Whether the cars are 20m or 23m has still to be finalised and will depend to a certain extent on existing route constraints.

The depot will be at Old Oak Common, this being the most practical location. However, with a planned HS2 station at this site, the planners have to ensure that there is no conflict on land usage.

More importantly, the opportunities for interchange with HS2 must be considered especially as the latter is not initially intended to directly serve Heathrow.

The stations through the central section will be an important feature of the Crossrail image. The plan is to build these with a common visual identity using common materials. All will have platform-edge doors, a uniform design for cross passages/adits and be equipped for in-cab CCTV for train/passenger security and safety monitoring.

The train length has determined that stations footprints will be large, many having multiple entrances several hundred metres apart.

At Paddington, the Crossrail platforms will be under Eastbourne Terrace with the present taxiway becoming a pedestrianised area with escalators down to the platforms. The Hammersmith &amp City Line station has to be rebuilt with new taxi facilities incorporating access from Bishops Bridge Road.

Bond Street will benefit from several new entrances and a connection to the existing Underground station which is also receiving a new entrance on the north side of Oxford Street – that’s being provided by LUL using Crossrail powers.

A whole new station is being constructed at Tottenham Court Road to augment the existing one, which itself will be rebuilt.

There will be several new entrances and two ticket halls, the eastern hall being six times bigger than the existing one with separate escalators to the Crossrail, Central and Northern lines.

As the interchange point with Thameslink, Farringdon will need to cope with 24 trains per hour on both routes as well as existing Underground services.

A complete new station is under construction with a western entrance sharing the new ticket hall being built by Network Rail for Thameslink. Another ticket hall will be built opposite Smithfield near to the Barbican.

Liverpool Street’s station will span between Liverpool Street and Moorgate with entrances on the latter, adjacent to the Broadgate office centre. Whitechapel will see a new station integrated with the Underground and Overground (East London) line stations.

Work is well underway at Canary Wharf with the station taking shape alongside the HSBC tower. Plans are to incorporate lots of retail development at this site.

Clearly these are massive works and extracting the spoil is a challenge in itself. At its peak, over 200,000 cubic metres will be taken out each month, with the removal from sites being by rail, barge or road dependent on the location.

To read Part 2 of this special 2-Part Series see next week’s Rail Express

Republished with permission from the UK’s The Rail Engineer&nbsp www.