Shani Wallis, Editor
It is a holistic approach that managers of Europe’s largest civil engineering infrastructure project of the moment have adopted for its design and procurement. Under that strategy, final design of all the TBM tunneling required for the central portion of Crossrail is in one project-wide package as is design of all the SCL/NATM work associated with the five underground mined stations. Crossrail has mobilized its management strategy and is ramping up population of that expansive central organization to move through the current design phase and on into construction by the end of 2009. A recent interview with Chris Dulake, Client Package Manager, Tunnels, Shafts and Portals, helped understand and appreciate the enormity of this civil engineering project and its programme chart into reality.
Full extent of the Crossrail link for London with interchanges to other public transit systems on central underground section
- Construction of more than 42km of EPB-bored tunneling, two cut-and-cover and four mined underground stations, and all the associated works that comprise construction of the massive £16 billion ($US24 billion) Crossrail project is the task of a major management organization being mobilized in London. Earlier this month and last, the project confirmed appointment of its Project Delivery Partner for the new underground rail link section under the heart of the capital and a Programme Partner to help coordinate all the various parts of this massive project and keep them all driving towards successful completion of the long-planned, often-postponed and much needed addition to London’s world-class but capacity-strapped public transportation system.
- The two private-sector Partners comprise some of the largest engineering firms in the world. San Francisco’s Bechtel, with Halcrow Group of the UK and rail engineering group Systra of France have landed the £400 million Project Delivery Partner post. The £100 million Programme Partner contract has been awarded to Transcend a joint venture comprising AECOM of the USA, parent of Faber Maunsell in the UK, with CH2M Hill of the US and the Nichols Group of the UK. Transcend will be integrated into the existing Crossrail team to form the Crossrail Programme Team. On confirmation of their appointments, these firms are now into the process of assigning individuals to offices in the project’s central co-location headquarters in Canary Wharf in London’s Docklands, an office address that occupies four floors of the Citi Tower in Canada Square and is capable of accommodating upwards of 1,000 people.
- Chris Dulake, the Project’s Client Package Manager, Tunnels, Shafts and Portals, has been with the project since April 2008 and has seen things progress rapidly over recent weeks towards the next major milestone - selection of design engineers for the many, varied and interrelated elements of the central underground section.
Fig 1. The central 21km-long underground section with its five mined stations
- The central underground section is the high-profile core of the larger 118km rail integration project from Maidenhead in the west to Shenfield and Abbey Wood in the east and involves construction of 21km of new twin-bore heavy-rail running tunnels and six underground stations to link Paddington Station in the west to stations at Bond Street, Tottenham Court Road, Farringdon Station, Liverpool Street Station, and Whitechapel, where it branches northeast to Stratford on to over-ground connections to rail lines north, and southeast to Canary Wharf in the Docklands and under the Thames to a new underground station at Woolwich and on over ground rail to link to southern networks at Abbey Wood (Fig 1).
- In starting the conversation with Dulake it was necessary to understand some background. Crossrail, the project, is owned by Crossrail Limited, a company with two public authority sponsors; DfT, the UK government’s Department for Transport, and TfL, the capital’s public transit authority Transport for London. Crossrail was first proposed as part of the Central London Rail Study in 1989 and has since seen intermittent activity and false starts. Through those intervening 20 years, the company’s main responsibility was to protect the underground easements and alignments, a responsibility it managed exceptionally well. In 2003 Cross London Rail Links was formed to resurrect the Crossrail project and Douglas Oakervee OBE was appointed Executive Chairman in 2005 tasked with guiding a hybrid bill to gain the powers to construct Crossrail through Parliament. In 2007 Prime Minister Gordon Brown announced that the £15.9 billion funding agreements were in place leading to Parliament passing the Crossrail Act in July 2008. In December 2008, the company became a wholly owned subsidiary of the controlling authority TfL and changed its name to Crossrail Limited.
- Since then, major management organizations and appointments have been mobilized. A new Crossrail Board with six Non-Executive Directors has been appointed and on 1 April this year, Rob Holden CBE, formally Chief Executive of London & Continental railways, became the Crossrail Chief Executive with Douglas Oakervee becoming Non-Executive Chairman after handing his chairmanship to Terry Morgan CBE as of 1 June 2009. Morgan is currently Chief Executive of Tube Lines Ltd, holder of the 30-year public private partnership with London Underground to upgrade the Jubilee, Northern and Piccadilly Underground Lines.
- Compulsory Purchase Notices were issued and property has been acquired at Tottenham Court Road to make way for major construction works at the site. Work at the Underground station at Tottenham Court Road, in advance of the Crossrail station works, has started and work at Canary Wharf also started this month (May 2009). Funding agreements have been signed with.
- BAA, owner of Heathrow Airport, for £230 million to include an underground spur link into the airport;
- the City of London, a major beneficiary of the project, for £350 million;
- the Canary Wharf Group for £150 million to include responsibility for design and construction of Crossrail’s station at Canary Wharf; and
- Berkeley Homes, the UK house builder, for design and construction of the Crossrail station box at Woolwich; and
- agreements underpinning governance of the project have been signed; and DHL has been appointed to recommend a logistical strategy to minimise impact of construction on central London.
Project scope and scale
“The complexity of a project like this is hard to grasp,” said Dulake. “At every point we interface with existing infrastructure, whether it is London Underground the underground central section at the stations or passing over or under
Typical layout of the mined underground stations with a ticket hall at either end and concourse links to parallel platform tunnels
- London Underground running tunnels; Network Rail at the over ground sections where we extend their services into the new Crossrail infrastructure; Thames Water for the many main line sewers that we either go over or under on the cross-London alignment; the many high-profile third-party property owners that we excavate tunnels under or shafts alongside; and all the traffic management, emergency services and resident and commercial groups who take special interest in what we are planning and preparing to undertake. Looking into any single element of the project, the design and construction of that element is a major undertaking in itself. At Pudding Mill Lane near Stratford at the eastern portal for example, an entire station and its section of existing railway has to be lifted and moved about 100m to one side to make way for Crossrail.”
- Managing realization of this construction effort is a huge undertaking and while there is a large core staff employed by Crossrail Ltd, it was decided that going out to the private sector to engage a Project Delivery Partner and a Programme Partner was the best way to get the best brain power, talent, and resources to gear up quickly for a project that will last over the coming eight years or so. “This also maintains the flexibility to change the composition of the management as each stage of project development progresses,” said Dulake. Crossrail has Client Package Managers (CPM) who will work in close association with members of the Project Delivery Partner’s team and the Programme Partner’s staff in one large co-location office in Canary Wharf. The idea of co-location is that all elements and members of the management team are in one place; with the right man for the job in the team and everyone close enough to limit “management by e-mail” and get up and walk over to the desk of a colleague to discuss a point.
- Other sub-partners in the project include London Underground, the Docklands Light Rail, the major utility companies, BAA; the Canary Wharf Group delivering the Canary Wharf station; Berkeley Homes, funding and delivering the station at Woolwich; and Network Rail, which is managing all the new surface rail and integration works, as well as eventually becoming the owner of the tunnels and stations on the new central underground section.
London knows well construction of large underground civil projects having completed in recent decades the London Underground Jubilee Line Extension (JLE) in the 1990s; construction of the underground rail extensions to the new Terminal 5 at Heathrow Airport which opened in 2008; and the recently completed and inaugurated Channel Tunnel Rail Link (CTRL), Phase 1 of which called for 19km of twin tube tunnelling under the northern suburbs of the city into the new international rail terminal at St Pancras, with major underground station works to link King’s Cross Station with St Pancras and a large open-cut station structure at Stratford.
Comparative tunnel sizes of London’s underground rail systems
- Crossrail however is a quantum increase on these previous projects. The alignment is directly underneath the very heart of London and all that that incorporates; it is a £16 billion project, while JLE was £3 billion and CTRL was £9 billion; and with six major underground stations on a 21km long underground route, it is two to three times the size of CTRL and JLE.
- In building Crossrail different strategies have been adopted. It will not be a design-build or contractor-alternative project as JLE was, nor will it be an ‘early contractor involvement’ process, as was used on Heathrow T5. Nor will it be a strict 100% design-bid-build procurement as used for CTRL. Instead it will be designed before construction bids are invited. At that time, contractors will have the opportunity to value engineer changes to improve constructability of the works. These ‘optimised contractor involvement’ suggestions will be incorporated into the final design once the contract is awarded and before construction starts.
- “The aim is for designers to own risk as well as the contractors,” said Dulake. “Engineers will design the works with the evident risks fully appreciated and accounted for, and the contractors will own the risks involved with the construction methods employed and the output. During construction, the plan is for design and engineering expertise to go on into the site management teams so that construction supervision is a fully informed process.”
Geological sections of the different central London underground routes
- The policy adopted by the team when Doug Oakervee arrived to take the helm and after overseeing successful completion of the new airport in Hong Kong, was to establish a holistic approach to the project - its design and construction. “We want to avoid situations where the same issues are addressed in three different ways,” said Dulake. “Where there is a common thread of design, construction or management for the full project this is grouped into one design or management string across the whole project. This we have adopted as the best way to manage a project of this scale.”
- With the Programme and Project Delivery Partners in place, the next major step in advancing the project is award of the design packages. In progressing this the management team has adopted a ‘framework’ approach. Design of all the SCL, sprayed concrete lining, needs on the entire project is covered in one package as is design of all the bored tunnel needs. Design needs are applied horizontally across the full project rather than vertically at different structures along the alignment. Design of all TBM running tunnels therefore are in one design package, with all SCL structures for all parts of the project in another. “There will be local geographic issues to be designed and managed,” said Dulake, “but in principle all the central tunnels are in London Clay or material suitable for EPB excavation or in chalk and suitable for slurry tunnelling.There is no need for three or four different designs of the segmental linings for example. With the SCL work, again there will be local geological issues, but basically the full toolbox of SCL design items need not be designed more than once for all the different applications across the full project. We don’t need two designers solving the same issue in two different ways.”
- Detailed design of the elements is being grouped into project-wide categories with these categories divided further into individual design contracts. For example one category covers shafts and tunnels across the central underground section and this is divided into separate design contracts for:
- all SCL work, including design of SCL work at intermediation shafts;
- the bored tunnels and covering all the segmental linings, specification of the TBMs, and rehabilitation of the existing Connaught tunnel on the southeast route to Woolwich that is being incorporated into the Crossrail alignment;
- civil design of the intermediate shafts (except for the SCL elements)
- aeordynamics and ventilation on the rail tunnels and at shafts and portals; and
- M&E works for tunnel lighting, walkways, drainage, fire mains.
- Another category covers design of the civil works at the stations (excluding the SCL work) with separate design contracts for each. A category for all the portals on the project is broken into contracts for the separate portals at Royal Oak; Pudding Mill Lane (with its relocation of the DLR station and rails); Victoria Dock portal in the Docklands; and the North Woolwich and Plumstead portals.
- Other project wide categories cover rail systems with separate contracts for rolling stock performance specifications, signaling and traction power, and the system control centre; and the communications and control systems.
Design of the instrumentation and ground movement monitoring requirements across the central underground section is a major undertaking and is currently being considered to be included in the design package of the bored tunnels and expanded to cover the monitoring needs at each of the underground stations as well.
- Construction plan
- Construction plan
Schematic of Tottenham Court Road station
Schematic of Liverpool Street station
- Over the past three years Crossrail has been working on the scheme design, which has rationalized and refined the preliminary design and feasibility studies. According to the current scheme design, the plan is for the twin tube running tunnels to be excavated using six EPB TBMs – two from the Royal Oak portal, two from the Pudding Mill Lane access shaft and two from the Stratford portal. Two slurry machines are likely to be used for the Thames River crossing between the North Woolwich and Plumstead portals. Issues concerning the exact sequence of construction are yet to be defined and these include the sequence at the stations where SCL station platform tunnels might be excavated first or the TBMs might be driven through the station zones for later breakout and expansion by the SCL works.
- Another major achievement of the scheme design phase has been elimination of eight permanent access/ventilation shafts on the central underground alignment. A principal effort of the Crossrail team has been to minimize the impact of the project’s construction on London - its commuters, its residents, workers, services, visitors and its daily routine. In that effort, elimination of the permanent shafts has avoided major construction sites in Hyde Park, in Hanbury Street and at six other sites along the central London alignment.
- “Elimination of these permanent structures from the infrastructure has been a collaboration of Crossrail and the London emergency services,” said Dulake. “Deletion of these intermediate ventilation and evacuation shafts has been made possible by the refinement of the underground structures – by including extra cross-passages to increase evacuation capacity between the running tunnels and by including full height platform edge doors at the underground stations allowing platform cooling systems in the stations. Engagement of the final designers will further fine tune these changes.”
- “No two engineering projects are ever the same,” said Dulake, “and there is still much to be confirmed and advanced in final design. Appointment of our detailed design consultants has progressed to an advanced stage. We have conducted several industry information days and design capabilities and specialisms have come together in design tenders we have seen to date. To comply with EU competitive tender regulations, we have prequalified interested designers and advance enabling-works contractors and it will be via mini-competitive tenders among these prequalified consultants and contractors that design and construction contracts will be awarded. The procurement strategy for the main construction contracts is yet to be finalized but the split of the construction contracts will not correspond with the design contract packages.”
- Tendering of the first design contracts started at the backend of 2008 and early 2009 and are expected to be awarded by this summer and the first main construction contracts are likely to be advertised in late 2009.
- Contracts for early enabling works, including service and utility diversions, have been let and are progressing. At the same time an extensive amount of work is being procured by Transport for London for upgrade and improvement works at the Tottenham Court Road station ahead of Crossrail work starting. There are the first signs of the immense activity that will carry on over the coming years toward successful completion of the project – on time and on budget – in 2017. There is much to be achieved before then!