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Crossrail: What's really delaying the £15.4bn mega-project

Crossrail Bond Street platform tunnels 3

Construction News investigates the detailed reasons behind the scheme’s nine-month setback – and whether more delays could follow.

“We’ve let people down,” Crossrail chairman Sir Terry Morgan told the London Assembly when he was hauled in front of its members last month.

“We were confident with a lot hard work we could get there, but we haven’t.”

At the end of August, Sir Terry and the Crossrail executive team confirmed to Transport for London the news it had expected for more than a month: the £15.4bn Crossrail project would not meet its December completion date.

The opening of the Elizabeth line would be delayed by at least nine months.

This news prompted mocking headlines, crisis meetings with the Department for Transport and disappointment for millions of commuters in the capital.

Having been envisioned for years as an example of how Britain could deliver major projects on time and on budget, the project had failed on both fronts – having revealed a £500m cost overrun in May. 

Many have been left asking how Crossrail has ended up in this state.

CN has spoken to those inside the project to reveal the stories behind the delays – and to ask whether we have seen the last of Crossrail’s problems.

Testing troubles begin

In autumn 2017, Crossrail was hit with a major crisis that led to questions around whether it could complete its construction works on time.

As chief executive Simon Wright admitted at the London Assembly meeting last month: “[In the autumn] we had increasing pressure on delivering infrastructure but still within the bounds of normal contract procurement; we were managing risks, we were looking at options to mitigate.”

Simon Wright programme director Crossrail

Simon Wright Crossrail

Crossrail CEO Simon Wright spoke at the London Assembly last month 

However, on 11 November this pressure ratcheted up significantly.

To ensure the testing of trains could begin on the central section of the railway, Crossrail needed to energise the overhead lines. As these lines were powered up, two transformers failed at the Pudding Mill Lane substation near Stratford, causing a major explosion. “That device failed quite dramatically, and we had to stop,” Mr Wright explained to the London Assembly.

A subsequent investigation discovered design flaws, and it would take until February for the problem to be fixed.

Crucially, the failure meant traction power could not be run on the overhead lines and the start of dynamic testing had to be paused, putting the project’s testing nearly four months behind schedule. And at the same time as the programme for testing was slipping, the separate fit-out work in the central tunnels was progressing more slowly than expected.

“These signalling systems are significantly more complicated than five years ago, never mind 10 years ago when we did the original planning”

Crossrail source

Mr Wright said in a written statement to CN: “The original programme for testing has been compressed by a delayed start and more time being needed by contractors to complete fit-out activity in the central tunnels, and the development of railway systems software.”

CN understands there is still work to do to complete infrastructure on the central tunnels, including the removal of temporary services and installation of permanent lighting and drainage pumps.

In his statement, Mr Wright said: “The construction works are coming to a conclusion but we need more time to test and successfully integrate the numerous complex systems to ensure a safe and reliable railway.”

A massive test

The explosion at Pudding Mill Lane had already set the start of testing back by four months. When the testing did eventually begin, the complexities of the task became apparent.

“When you go under the bonnet of these signalling systems they are significantly more complicated than they were five years ago, never mind 10 years ago when we did the original planning,” one project insider says.

Mr Wright told the London Assembly that by spring 2018, Crossrail was having limited success on its testing programme. 

Fast-forward to today, and the majority of its testing and commissioning should have been completed. However, CN has been told it is well behind that target. “It is hard to put a figure on how much is completed, but I would say indicatively half of it is done,” the insider says.

Crossrail class 345 train

Crossrail class 345 train

Testing the key systems is taking longer than planned

The programme involves hundreds of tests, which are being carried out across three different signalling systems. The reason for the variation in signalling is that Crossrail interacts with different existing rail infrastructure at either end of the line. 

The central section of the line between Paddington and Abbey Wood uses a Communications-based Train Control system (CBTC); the Great Western and Great Eastern Main Line (on which Crossrail trains will run) uses the Train Protection Warning System (TPWS); and the Heathrow tunnels use a European Train Control System (ETCS).

“They are all doing many hundreds of tests, and it is only over a period of time that you realise that the outcome isn’t going to be right”

Crossrail source

When Bombardier’s trains eventually start transporting passengers, they will have to transition across all three signalling systems. Integrating the trains to these systems and ensuring the software works across all three has caused problems. The work involves writing, testing and then upgrading software across the three systems and on the trains, which has been far more complicated than first expected.

“You have these different organisations with different bits of kit that need to be brought together,” the source says. “They are all doing many hundreds of tests that need to be done, and it is only over a period of time that you realise that the outcome isn’t going to be right.”

In his statement to CN, Mr Wright said: “The Elizabeth line is one of the most complex and challenging infrastructure projects ever undertaken in the UK and brings together multiple contracts, new rolling stock and three different signalling systems.”

Crossrail’s Catch-22

These difficulties have been compounded by the slower-than-expected installation of infrastructure in the central tunnels, which has limited the progress of complex testing as fit-out work continues.

Multiple sources on the project have told CN that these tests have been taking place for only three days every couple of weeks. Such short testing periods have not allowed enough time for issues to be properly resolved, they claim.

Crossrail has been left in a catch-22 situation: does it continue to carry out testing and fit-out work simultaneously and slow down both, or does it finish all of the remaining infrastructure work so testing can take place when the contractors have left the tunnels?

The Crossrail insider tells CN that bosses had opted for the second option. “If we try to do piecemeal it will end up like [the] Jubilee line, which took forever,” they say.

“If you speak to the contractor, they would say ‘late changes’; if you speak to Crossrail they would say ‘slow implementation of change’”

Crossrail source 

In 2010, it was revealed that upgrading the Jubilee line had been delayed by more than a year after the testing of its newly installed signalling system uncovered a series of failings.

“The idea bluntly is to finish on site and leave the specialists to [do] testing and commissioning,” the source says. “[We would] effectively [be] giving those carrying out the tests an open tunnel and completed railway so they can do things in one [go], rather than piecemeal.”

Bond Street delays

Crossrail’s stations had been due to be near-complete by now, but work on the majority of them is still ongoing. Crossrail has told CN that the remaining work on the stations is largely around architectural fit-out and MEP installation.

It expects most of the stations will be fully completed by the end of the year. There is one exception, however: Bond Street.

Progress on Bond Street sticks out like a “sore thumb”, one source says.

For years, testing ground conditions meant many had singled out Whitechapel as the station most likely to be finished late. Instead, it is Bond Street that has emerged as the most challenging station. “The last 18 months, [progress on] Bond Street has been a basket case,” the project insider tells CN.

Platform construction for Bond Street Crossrail station

Platform construction for Bond Street Crossrail station

Bond Street has proven particularly challenging

The £110m contract is being delivered by Costain and Skanska – whose JV is also delivering the £147m Paddington station upgrade works.

CN understands that significant pieces of equipment had been installed late at Bond Street, which was having a knock-on effect on the programme.

Commenting on the reasons behind the delays, the source said: “If you speak to the contractor, they would say ‘late changes’; if you speak to Crossrail they would say ‘slow implementation of change’.” 

They added: “If the trains had been ready […] to run in December, then [Crossrail] wouldn’t have been able to open Bond Street.”

Crossrail has told CN that the delays were due to the complex station build required.

CN understands that the Bond Street works are expected to be complete well before the autumn opening date next year, and are not one of the major reasons for the delay of nine months. When asked for comment, Costain and Skanska referred CN to Crossrail.

The alternative plan

Since the announcement of the overall scheme’s delay, there has been a wave of criticism of Crossrail’s management – not only due to the delay but also the manner in which key stakeholders were informed.

At an assembly meeting at the start of September, mayor of London Sadiq Khan said he was only officially told of the length of delay two days before it was announced on 31 August. 

“What we don’t want is a Thameslink; we want this stuff to work and get it right first time”

Crossrail source

According to chief executive Mr Wright, Crossrail had been issuing warnings over potential delays to sponsor boards since May and June.

Mr Wright told the London Assembly that on 19 July, he “informally briefed” the board that Crossrail was not confident of meeting the December completion date. Chairman Sir Terry Morgan sent the executive team away to see if there was any way to mitigate the delay. After suppliers were consulted, a new completion date of autumn 2019 was agreed and confirmed at a board meeting on 29 August.

Commenting on the delay, Mr Wright said in his statement to CN: “Over 10,000 people have spent 10 years working to deliver this railway but we have been managing a number of significant schedule pressures as the project approaches completion.”

The project insider speaking to CN claims the problems leading to the delay were cumulative, and that the possibility of delay had been suggested for some time. “It’s not come up and bitten Crossrail by surprise; the testing and commissioning has been going on for a year,” they say. 

The source says discussions took place around opening Crossrail earlier than next autumn. “We were looking at instead of opening in the autumn, could we open it in March or July? There were alternative dates being considered. You only have one chance with a delay. 

“What we don’t want is a Thameslink; we want this stuff to work and get it right first time. Because of the scale of this thing, [with] all of the stations [and] all of the other things, it has to be absolutely right on day one.”

The final countdown

Crossrail has vowed to complete both the railway infrastructure works and station fit-outs, bar Bond Street, by the end of the year.

However, the exact completion date appears to remain uncertain. This was reflected in an interview with Mr Khan earlier this week, in which the mayor said he could not give assurances that Crossrail would be finished by next autumn.

“Until you get into this process of fixing bugs, it is very difficult indeed to be definitive and know how many times you have to go through the cycle”

Simon Wright, Crossrail

The mayor’s office has commissioned two independent reviews to assess whether the project’s autumn 2019 assumptions are realistic.

Full dynamic testing of the line is scheduled to start on 22 October, and Mr Wright told the London Assembly it could still be three or four months from this date until Crossrail knows exactly when it is likely to open. The programme will involve a series of tests, followed by what he described as “fixing the bugs” and upgrading software if issues are found. This process will need to be carried out multiple times.

“Until you get into this process of fixing bugs, it is very difficult indeed to be definitive and know how many times you have to go through the cycle,” Mr Wright said. “We have made an allowance, we have made an estimate and we also allowed risk against that; we have been quite cautious and careful about these estimates.”

Nevertheless, it is possible that these processes could take longer than planned – particularly if a safety-critical problem is found. 

“There are circumstances you can envisage [of] having a safety-critical software problem late on, which would be difficult to deal with because they need more time to fix,” Mr Wright said. “It is not likely we will find one because we hope to find them on the test rig, test track or on 22 October, but it is possible.”

CN’s source suggests the delay could prove beneficial for TfL, as it will have the opportunity to prepare its staff for when doors open on the new line.

“It does give TfL a good chance to train staff for when it does open,” they say. “It’s not going to be the Greek Olympics situation; all the staff will be very used to the new stations.”

Despite these minor upsides, TfL, Crossrail and their contractors are now locked into making sure the project does not end up facing more hard questions this time next year.

In full: Crossrail CEO’s response to CN’s findings

Crossrail chief executive Simon Wright said in a statement to CN: “The delay is hugely disappointing. No one could have tried or worked harder than the teams that support Crossrail.

“Over 10,000 people have spent 10 years working to deliver this railway, but we have been managing a number of significant schedule pressures as the project approaches completion.

“The Elizabeth line is one of the most complex and challenging infrastructure projects ever undertaken in the UK and brings together multiple contracts, new rolling stock and three different signalling systems.

“The original programme for testing has been compressed by a delayed start and more time being needed by contractors to complete fit-out activity in the central tunnels and the development of railway systems software.

“The construction works are coming to a conclusion, but we need more time to test and successfully integrate the numerous complex systems to ensure a safe and reliable railway.”

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