IT might seem premature to imagine the first trains running when even the company responsible for constructing Britain’s second high-speed line, HS2 Ltd, is quoting a four-year window for its completion.

But rail passengers travelling into Birmingham’s New Street and London’s Marylebone stations already have a very real sense that one of Europe’s biggest construction projects is making tangible progress. They can see for themselves, respectively, the foundations of HS2’s northern terminus of Birmingham Curzon Street taking shape and the elegant Colne Valley viaduct at the southern end of the route near West Ruislip extending itself, concrete segment by concrete segment, for more than 3km over lakes and waterways to form what will become Britain’s longest railway bridge.

A total of six tunnel boring machines (TBMs) are currently burrowing their way through a mixture of ground types and tunnelling on HS2 is already estimated to be around 50% complete overall. In total, approximately two-thirds of the budget for civil engineering work between London (Old Oak Common) and Birmingham has now been spent.

After several years of uncertainty caused by rising construction costs and political equivocation, culminating last October in the cancellation of all sections of HS2 north of Birmingham, the future for HS2 is now much clearer. Phase 1, 225km between London and Birmingham, with a connection north of Birmingham to the West Coast Main Line at Handsacre is now the only phase that will be built (see panel below).

The most southerly part of the route, the 13km tunnelled section between the major hub interchange at Old Oak Common in west London and the terminus at Euston in central London, has been paused for at least two years, while the government assesses the viability of attracting private-sector finance to complete this stretch.

After the turbulence of recent times, including the departure of CEO, Mr Mark Thurston, last autumn - his replacement is expected to take up their post this summer - and reams of negative media coverage, to attempt to get the project back on track might seem a brave undertaking. Yet this is exactly the challenge that HS2 Ltd’s chief rail officer, Ms Emma Head, accepted when she began work earlier this year.

With two decades of civil engineering experience in rail, and a member of HS2 Ltd’s executive team since 2015, Head is just the kind of person the project needs, especially as 11 major contracts are due to be awarded later this year (see table below).

When she sits down for an exclusive interview with IRJ it is immediately apparent Head has the whole route very clearly imprinted on her mind, as she talks seamlessly about each section without hesitation or recourse to maps or other paperwork.

She explains that her role emerged as a direct result of lessons learned from Crossrail, the £18.8bn project to build a new east-west rail tunnel across London, where the first trains began running on what is now the Elizabeth Line in 2022. In the heat of construction, with many contractors on board, it became evident that responsibility for managing certain tasks was unclear.
“So HS2 Ltd has mapped all of the interfaces between the construction packages and between the systems where we expect there to be interfaces that need to be managed, and which contractor we believe should be discharging that integration activity,” Head says.

“My job is to keep an eye on the key decisions to make sure they will come together to deliver an end-state railway and I have the power to instruct change and make better programme decisions where I can see a new scope or a need to alter delivery to make sure we protect that end-state outcome.”

Head admits that she has already had to make changes surrounding railheads and placeholder assumptions on behalf of systems. “One thing we’ve done which I think is unique in our rail systems contracts is that we’ve specified that HS2 will undertake a role we’ve called prime system integrator, where we’ve identified multi-face interfaces, which are the hardest to integrate and are often critical,” she says.

“We will retain accountability for each one and we will actively integrate it, rather than outsourcing it to a supplier. One of things I’m trying to work out now is what are the critical pinch points and not shy away from them.”

Head is keen to point out that many other lessons learned from the construction of Crossrail have been taken on board by HS2 Ltd. These include software integration and performance measurement. For the former, although many software systems are off-the-shelf products, they each have individual update cycles, which can impact on other systems. HS2 has already appointed a head of software, so that assumptions of how software systems will work can be mapped out and monitored in real time. “There are around 200 software systems needed to build HS2, but only 10 are critical,” Head explains. “Without having gone through our initial analysis we wouldn’t necessarily be aware of that, whereas we certainly are now.”

Measuring and managing performance should allow HS2 to avoid some of the public relations disasters experienced by Crossrail when key milestones were missed. “I remember speaking with my colleagues at Crossrail when they thought it was 90% complete. Not long after, they told me it was only 68% complete because they realised that things hadn’t been built,” Head says. “So, we’re making sure that we really understand technical debt. And when we proceed to build something, we are clear what is owed to us later.”

While Crossrail has certainly proved useful for navigating around potential system integration pitfalls, it does not provide a comprehensive blueprint, as the project involved tunnelling under London and the use of existing infrastructure at either end, therefore avoiding many of the planning issues that HS2 Ltd is contending with in order to build a new railway between London and Birmingham. With a mind-boggling 8500 individual planning consents required for Phase 1, Head has her hands full ensuring that planning conditions, especially those around environmental impact and risk, are properly met and construction schedules managed accordingly.

As a delivery body, working on behalf the British government via the Department of Transport (DfT), HS2 Ltd has also had to navigate the fallout of political decisions, over which it has no control. Head won’t be drawn on how a potential change of government (a general election must take place before January 2025 - see panel above) might affect prospects for reinstating those sections of HS2 cancelled by the current administration. Nor will she comment on the ongoing debate over the rising costs of the project (see panel below) - those are matters for politicians, she insists.

Head is, however, able to clarify a couple of points that have been widely misunderstood in the British media. One relates to the paused tunnel section to Euston. Reports that tunnelling has already started at Old Oak Common are wide of the mark, she says. To allow progress with extensive surface work at Old Oak Common, the two TBMs that will bore the tunnel will be lowered into their launch chambers later this year. Head says this is part of the preparatory work for the Euston tunnels, which is funded to 2025. Until a decision has been made by DfT on proceeding with construction, the TBMs will remain stationary, effectively buried at Old Oak Common.

Head is also able to shed light on potential service levels and routes to be served by the new high-speed train fleet, construction of which is due to start next year (see panel below). “We don’t have a formal set of revised train specifications from DfT yet, but we’ve been given the working assumptions that we can use to mature our design with,” Head says.

These assumptions are that three 400m trains, each composed of two 200m-long high-speed trains with a total capacity of around 1000 passengers, will run every hour between Old Oak Common and Birmingham Curzon Street. And, when the Handsacre spur is complete, an additional six single 200m trains per hour will run from Old Oak Common directly to destinations north of Birmingham.

Suggestions that the 400m trains will split or join at Birmingham are firmly dismissed by Head. “There’s no time benefit to that,” she explains. So, at present, there are not expected to be any direct trains between Birmingham Curzon Street and the north of England and beyond. This means that the line connecting Birmingham and the Handsacre spur will not be used in regular service.

For the trains running through from London to destinations on the conventional network north of Birmingham, HS2 is working with the manufacturers on detailed design issues, such as how to achieve level boarding after the trains leave the HS2 network. “The Network Rail stations that the trains might be able to stop at include platforms that don’t have a consistent height and tracks that don’t have a consistent cant and profile,” Head says.

The V-shaped piers that carry HS2 into Birmingham Curzon Street have been specially designed to maximise space on the ground.

“We found the [single]-step configuration challenging and so we are now looking at a two-step solution, which is able to deploy differently, yet optimises safe use on both networks. That is a change driven by us. I’ve been asked if infrastructure enhancements would work instead, but that means doing it to every station you might stop at, so it’s much better to do it using the rolling stock.”

The two-step solution, which has already been implemented in Florida, adds a couple of seconds dwell time at each stop, as the train’s software assesses which step configuration to deploy, but Head is convinced that this is the most viable way of achieving level boarding at all stations.

While Head focuses on the myriad of unresolved issues relating to rolling stock, infrastructure and systems, one key question remains: when will the line open for passengers?

Perhaps learning again from Crossrail and the Elizabeth Line, which very publicly missed a succession of opening dates, HS2 Ltd hasn’t specified a precise opening date or even tied it down to a specific year.

“It will be sometime between 2029 and 2033,” says Head, whose appetite for hard work and solid results suggests that opening will come sooner rather than later.