HS2 is Showing Real, Measurable Progress on the Ground

After a long stretch of reversals and damaging headlines, High Speed 2 is now delivering tangible, trackside evidence of momentum. The civil engineering increasingly looks like the foundations of a working railway rather than a concept note on a minister’s desk. A refreshed leadership approach is intended to lock down scope, costs and dates, and convert the UK’s TGV-style vision into services people can genuinely use.

What has actually changed on the ground

The latest construction figures suggest a clear shift from planning to delivery. HS2 says close to 70% of the twin-bore tunnelled route is now complete - 61 of 88.5 kilometres. A major marker has also been reached with the long, deep Chilterns tunnel breaking through, a milestone for both site teams and programme managers.

Bulk groundworks are likewise progressing beyond paper plans. About 92 million cubic metres of spoil and fill have been moved so far, which HS2 puts at 58% of the overall earthworks programme. This is significant because tunnelling and earthworks sit on the critical path that enables track, electrification, signalling and, eventually, passenger operations.

Structures are advancing in parallel. Construction has started on 158 of the 227 viaducts and bridges within scope, and 13 structures are already standing. The most prominent is the Colne Valley Viaduct: a 3.2-kilometre span over water and wetlands near London. Once finished, it is set to be the UK’s longest rail bridge and will define the alignment and geometry for the approach into the capital.

Metric	Status
Tunnelling	≈70% complete (61/88.5 km)
Earthworks	58% complete (≈92 million m³ moved)
Viaducts/bridges started	158 of 227
Structures erected	13
Flagship bridge	Colne Valley Viaduct, 3.2 km
Design speed	Up to 360 km/h (planned)
Cost range (latest public estimates)	£67–83bn; some scenarios up to £104bn (~€126bn)

HS2’s civil works are no longer hypothetical: most tunnelling is delivered, heavy earthworks are past halfway, and the UK’s longest rail bridge is rising.

The cost reset now under way

Chief executive Mark Wild has initiated what he describes as a fundamental reset of the programme. His team is carrying out an end-to-end review and re-costing items across the build - from ballast and rebar through to the unit price of each rail. The objective is to bring stability to a budget that has drifted higher under inflation, shifting scope and schedule slippage.

Why the budget blew up

The overspends have come from multiple directions. Worldwide inflation in materials pushed up the price of steel, concrete and energy, while the labour market became more constrained. Engineering challenges below London and through the Chilterns increased complexity, contributing to longer tunnel drives and more substantial linings. At the same time, property compensation and environmental mitigation requirements grew. Changes in one area also triggered redesign and rework elsewhere, rippling through supply chains and delivery packages.

Current public estimates tend to sit between £67 and £83 billion in today’s prices. In some higher-end scenarios, the total reaches £104 billion, roughly €126 billion. The reset is meant to limit further escalation by freezing scope, re-sequencing works to cut idle time, and combining procurement to extract better value through scale.

A formal reset targets three outcomes: a smaller realm of uncertainty, earlier visibility of risk, and a cost curve that finally flattens.

What passengers would actually gain

HS2 is intended to do more than shorten journeys out of London: its central promise is capacity. Shifting intercity services on to new high-speed infrastructure should release train paths on the existing West Coast Main Line for additional commuter services and more freight. In turn, that can improve reliability into major stations and help move lorries off the motorway network.

Speed, capacity and regional impact

• Faster end-to-end trips: projected London–Birmingham in around 50 minutes once the high-speed section opens.
• More local services on existing lines, as long-distance trains shift to HS2.
• Freight growth potential, with new slots on key arteries to support ports, parcels and supermarkets.
• Better labour market reach, linking firms to deeper pools of skills and suppliers.
• Construction and engineering jobs across the corridor, with skills that transfer to future net-zero projects.

The parts that still worry ministers and taxpayers

Last year’s decision to drop the northern leg beyond Birmingham turned that section into a political casualty and reduced the overall footprint of the scheme. That change reshapes the benefits case and increases the pressure on Phase One to perform without further disruption.

London Euston remains another politically and financially sensitive point. The current approach is to begin operations into Old Oak Common first, then finish and fund Euston using a development-led model. While this staging can lower near-term spending, it also requires tight coordination between station construction, property partners and the railway’s core systems.

Risk has not disappeared from the delivery picture. The condition of the supply chain, utilities diversions, uncertain ground conditions and the challenges of systems integration can still cause disruption. For the reset to work, the programme has to map these interfaces in calendar-level detail and ensure funding flows to the right activities at the right time.

Where the project goes next

The next phase should look more industrial and repeatable - and that is positive. Delivery teams will move into track slab pours, overhead line installation, long runs of fibre, and full signalling integration. Viaduct construction should progress across open country with a steady cadence of segments, bearings and deck work. Tunnels will be fitted out with walkways, power supplies and evacuation systems. Each finished work package reduces uncertainty and narrows the list of open risks.

Key milestones to watch

• Completion of remaining tunnelling drives and portal structures.
• Colne Valley Viaduct deck closure and trackbed installation.
• First continuous track laid between two major structures.
• Traction power substations energised and initial systems tests.
• Trial running on a defined test section before passenger certification.

What this means for the wider rail network

A high-speed railway changes timetables well beyond the places where concrete is poured. Once faster services are removed from older routes, conflicts at junctions tend to reduce, making it easier to plan simpler, regular clockface services for communities that may never see a high-speed train. Freight operators can also gain more consistent paths, supporting decarbonisation by shifting more loads from road to rail.

There is, however, an unavoidable climate trade-off. Building major infrastructure creates substantial emissions upfront, while the benefits come later through modal shift away from short-haul flights and longer car journeys, and through reduced motorway congestion. Clear reporting on whole-life carbon will matter as much as the number of minutes cut from end-to-end journey times.

A quick guide to reading the next cost headlines

As the next set of HS2 cost figures emerges, three checks can help interpret them. First, are the numbers stated in out-turn prices or in today’s money? Inflation alone can add billions without any change in scope. Second, what is included in the scope? Euston, rolling stock and local upgrades can be moved in or out of headline totals. Third, how large is the contingency, and who has authority over it? Strong governance determines whether contingency is a genuine buffer or effectively an open-ended commitment.

Practical notes for travellers and businesses

For organisations along the route, works will continue to affect local roads, access arrangements and utility services. It is sensible to engage early with local HS2 teams about deliveries, site access and staff travel planning. For passengers, the earliest noticeable upside may be improved performance on classic lines as temporary works conclude and disruption from possessions reduces. It is also worth watching for timetable changes around major bridge completions and junction works.

Context that helps the debate

France’s TGV and Spain’s AVE provide examples of how a high-speed backbone can reduce pressure on older routes and connect regions more effectively. In the UK, the chosen approach threads through denser urban areas, tighter environmental constraints and more congested utility corridors, increasing both risk and cost. Equally, once operational, HS2 should ease pressure on some of the most heavily used tracks in Europe while offering a template for how future megaprojects can be governed.

If the reset succeeds, HS2 can still deliver the original intent: speed where it makes the biggest difference, capacity where the network most needs it, and a modern mainline for a railway system that has reached its limits. The change is now visible on site. The next challenge is to keep delivery steady, predictable and on schedule until the first train glides into a newly built platform.