HomeHigh Speed RailThe capacity benefits of HS2

The capacity benefits of HS2

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People are now beginning to understand that the main reason for investing in the new North-South rail line is the improved capacity and connectivity it will bring to the major cities served on the core network. Writes Andrew McNaughton, Technical Director of HS2 Ltd

Both the Department for Transport, in its Strategic Case for HS2, and Network Rail as owner and manager of the existing GB rail network, have published substantial reports on the capacity question. In this article, I want to look in more detail at the capacity issues that HS2 addresses and examine the challenges of the growing railway and the opportunities the extra capacity this investment brings.

Back to basics

The initial HS2 “Y” network is being delivered in two phases. Phase One will run between London and the West Midlands. It is now in the Parliamentary stage with the deposit of a hybrid Bill on 25 November that will give planning permission to build and operate the new line. This phase also includes a connection to the classic network near Lichfield on the West Coast main line (WCML) so that, from 2026, HS2 trains can travel directly to Manchester, Liverpool and Glasgow.

We are currently consulting on the preferred route of the second phase that extends the line in two arms – the western one to Crewe, Wigan and Manchester and the eastern one through the East Midlands and South Yorkshire to Leeds and York. This phase is planned to be in operation by 2033.

Research from the Government and Network Rail demonstrates that there is strong and continuing growth in rail travel in Great Britain. This is driven by population increasing (with a central forecast for England alone of some 30% by 2050), economic growth and public policy to use more sustainable transport modes. And all of the evidence so far shows that developments in mobile information technology and telecommunications have led to people travelling more not less.

West coast crunch

Whilst the WCML is not the only long distance line facing a capacity crunch in the coming years, it is the one where three factors combine to make the impacts come earliest and most severely.

First, it serves half of the ten biggest city regions – Central Scotland, Liverpool, Manchester and London. Since the, albeit curtailed, WCML Upgrade was completed in 2008, long distance travel aided by more frequent and attractive services has grown very strongly indeed.

Secondly, the same tracks are in demand for rapidly increasing commuting into those major conurbations and to serve the growing region centred on Milton Keynes and Northampton. Milton Keynes, in particular, already sees very frequent trains taking up much of the available capacity – it’s just that they are busy long distance ones passing through without stopping!

The WCML is also the primary long distance freight artery of the country with good rail access to the freight terminals placed in the major cities. Some 40% of the nation’s rail freight needs access to the WCML for part or all of its journey.

This combination of fast, commuter and freight trains means that the practical capacity of the WCML is being used already and, as with any system being run at or near full capacity, reliability is vulnerable to any hiccup. Like any long established, mixed traffic railway, its theoretical capacity is reduced by the mix of train speeds, stopping patterns and location/configuration of stations and junctions with all the conflicting movements that inevitably brings.

Of course existing trains can be – are currently being – lengthened and pricing can be used to some degree to incentivise people to travel at less busy times. Adding carriages to the Pendolino trains and potentially altering the mix of first and standard classes can add some 150-200 seats to every long distance train. And turning the commuter network into one where 12 carriage trains in the peak are the norm makes common sense.

More is needed

281_INTERIOR_002m_camSMARTGLASS_C2 [online]
Windows of new HS2 trains could include ‘smart glass’
That is the recipe to manage growth until HS2 comes on stream, but is not a longer term-solution. Widening the existing railway through the multiplicity of cities, towns and villages which have built up around the existing railway is simply impractical without dramatic demolition. And there would be unimaginable disruption to rail services while trying.

So it is generally agreed that the country needs a new north-south railway to provide the capacity our growing country needs. And as other countries have found, building it high speed provides new connectivity with greatly reduced travel times at modest additional cost. We have shown that the incremental cost of a high speed railway over a conventional one is no more than 10%.

The first phase of HS2 will be most useful in releasing capacity to recast the south end of the WCML and the corridor through Coventry into Birmingham. The former will then accommodate the growth into London and the latter high frequency metro style services that Centro envisages. The Milton Keynes / Northampton area could see the frequent fast services the growing population of that expanding area will warrant. It is perfectly practical to see a fast service of London – Watford – Milton Keynes – Rugby/ Northampton at a ‘metro’ frequency of 10 minutes or less.

Both of these fast services would naturally continue beyond Rugby towards Coventry and Birmingham Airport, and northwards serving the principal Trent Valley towns. These in turn, with the introduction of Phase Two of HS2, could continue, in the capacity then released, to provide frequent services towards Stafford and Stoke-upon-Trent. We should see Milton Keynes as the new hub with trains heading towards many points of the compass – London, Oxford, Wolverhampton and Birmingham, Stafford and Liverpool, Stoke-upon-Trent and Manchester. This is simply not possible without the capacity HS2 releases along with the parallel investment in the existing network to which the government continually emphasises it is committed.

Additional services

This is not only about capacity in terms of raw seats or trains, it is about fashioning an attractive timetable maximising connections at the hubs along the route. For example, Watford connects through to Clapham junction and Croydon to the south and Milton Keynes will connect to Oxford on the about to be restored and modernised East-West route. The list is significantly long; think of the connections at Rugby, Nuneaton and Tamworth.

Then there are the potential areas which could be served for which there is no capacity today – Shrewsbury via Wolverhampton, for example.

We estimate that the nine non-stop train paths initially replaced by HS2 services could be replaced by a greater number of freight and passenger trains – the latter particularly serving Milton Keynes – because the end-to- end speed differential between the fastest and slowest trains would be reduced.

The exact traffic mix in the future between freight, medium-distance and regional passenger trains will dictate the practical reliable capacity. A rule of thumb has been that HS2 releases around 11 train paths per hour on the WCML fast lines. Meanwhile HS2 itself, designed as a high capacity system with longer trains all running at exactly the same speed, will provide twice the seating capacity of those WCML fast lines.

Of course the industry, led by Network Rail, will not be proposing an exact timetable until we are nearer HS2 opening in 2026. However, discussions are already taking place to prioritise the valuable space on the southern part of the WCML for when that day eventually arrives.

More to come

Phase Two of HS2 opens up greater possibilities again. Extending the western leg of the Y Network to near Wigan by- passes all the capacity constrained areas south of Manchester and really increases the opportunities for freight. Every container freight train is the equivalent of taking 40 lorries off our roads. So to add one or two additional freight paths every hour through the day quickly adds up to thousands of long distance lorry journeys that are not needed.

It is after opening the second phase of HS2 that a more radical approach to use of the released capacity of the WCML can really be introduced, bringing limited-stop direct services to places which cannot be served today. Exactly where will need to be the result of wide scale consultation and analysis of potential markets by the industry and government nearer the time, but it is not hard to see centres like Blackpool and other East Lancashire towns benefitting. And with these trains also stopping at places such as Milton Keynes, a new classic rail network of direct journey opportunities by fast rail will offer a credible, low-carbon, attractive alternative to the car.

Piccadilly - Perspective Drawing_0 [online]
Artist impression of Manchester Piccadilly Station.
Meanwhile HS2, with its capability to run pairs of 500+ seat trains as a single service, could serve even more destinations than has been included in the current business case. With classic line electrification, Chester and North Wales could easily be added to Warrington as destinations for single classic-compatible trains separating from Liverpool services at Crewe. Of course it is likely that there will need to be some capacity improvements on the WCML immediately north of Crewe but that will be necessary anyway to realise the freight growth potential from the new Liverpool port investment nearing realisation. And, rather than terminating at Preston, HS2 trains could easily be extended north to provide faster direct services from London and Birmingham to stations towards Carlisle.

The Y-network also releases significant capacity on the Midland and East Coast routes south of Leicester and Leeds/York respectively. Although much focus initially has been on the potential for meeting outer London and longer distance commuting growth, opportunities to introduce new long distance flows will also exist. For example, with limited infrastructure investment, major cities such as Bradford and Huddersfield could see services to London once again directed on the main line through Wakefield, giving the latter potentially more trains per hour to London than even today. These would complement the already planned frequent quick regional connections to the HS2 stations at Leeds, Meadowhall and Toton.

All the time, we need to remember that HS2 is adding huge capacity and giving us the chance to connect a great number of towns and cities in the North and Midlands to the South. It is not just about speeding up journeys between the major conurbations.

Another exciting chapter is about to be started in the HS2 story; that is exploring the case for journey time reductions north from Leeds and Manchester on the WCML from Preston over the ‘northern hills’ of Shap and Beattock. This is where it currently runs at near-capacity through the timetabling challenge of combining intercity, stopping passenger and freight trains.

So the joint study recently announced by the Westminster and Scottish governments looking at extending HS2 to Scotland will be considering capacity as well as speed – to create a stronger and better backbone linking the cities of the Scottish central belt with their trading partners of northern England, the Midlands, and then on to London and the south. After all, why shouldn’t the twenty-first century journey from Liverpool to Glasgow be quick, frequent and attractive – we just have to overcome the consequences of nineteenth century history.


  1. “People are now beginning to understand that the main reason for investing in the new North-South rail line is the improved capacity and connectivity it will bring to the major cities served on the core network.” Which people? Please cite some data to back up your claim. These are ‘talking points’ which are all part of a plan to make the actual public think people are on board with HS2. I have news for you; they’re not.

  2. This seems like a sensible and well argued piece to me. There will always be people opposed to new large scale projects (remember all those people who were against the Olympics?). Capacity is the key, and if building a new line, it may as well be a fast one.

  3. Lobbyists in Parliament PR a project (without any concern to the environment or the taxpayer) that will line the pockets of some and rob the pockets of others. simple, HS2 is not about quality or national need, its about greed. stopHS2.

  4. This article is linked directly from the STOPHS2 website, which is populated largely by activists who just happen to live within close proximity of the planned pathway for HS2, eg. mopdenson who lives in Great Missenden – now there’s a coincidence?

    • Indeed. Whenever an articulate article appears that explains the logic & pragmatic vision behind Hs2 you can guarantee the vociferous minority from the anti Hs2 campaign will try and hijack it. Mostly, they hide behind pseudonyms to make their numbers appear larger. The reality is different. They had a national rally in London last November. Less than 200 people turned up!

  5. What’s absent from this article is a *quantification* of what capacity would be released by HS2, and its monetised value. People need to treat HS2 Ltd’s claims with extreme caution.

    Claims like, “The Y-network also releases significant capacity on the Midland and East Coast routes south of Leicester and Leeds/York respectively”, are daft, because MML and ECML path utilisation is pretty low.

    The Wolverhampton – Shrewsbury line is not running at capacity, so why there is a ‘capacity constraint’ preventing Euston ICWC trains running beyond Wolves, is difficult to understand.

    The twin-track Birmingham – Coventry line carries a mix of stopping and semi-fast LM, intercity Virgin ICWC and XC, and railfreight. Centro’s intention is that 2 of the 3 London ICWC trains each hour would continue to run, alongside HS2. Clearly, removing just 1 intercity train from the current mix is not going to enable a “metro-style” service between the two cities.

    The 200-metre AGV11 in service in Italy (HS2 Ltd’s Reference train) only has 460 seats. So the chances of a 400-metre HS2 train having double the “capacity” of a 265-metre classic train, seem quite low. And it’s likely that around half the services in the Y network, would be based on 200-metre trains.

  6. We do need the capacity of HS2. Our railway is expanding faster than those of our continental neighbours because we had decades of underinvestment by a road biased Government transport department.
    Even the Transport Select Committee say ” it is essential for the UK for HS2 to go ahead”. And they have taken a much better balanced view than the spin doctors.
    HS2 will deliver more train path capacity per £ billion than the upgrading of the west coast main line did.
    Yes there are flaws with the present plans for HS2 such as terminal stations at Birmingham, Leeds and Manchester which severely limit the geographical area that benefits from HS2’s speed. The use of out of town stations could severely restrict the economic growth of city centres such as Nottingham, Sheffield and Derby rather than grow them. The connections with international gateways at Heathrow and the channel tunnel as proposed are simply not at all adequate. But even with those limitations, HS2 will deliver the capacity of a brand new railway and offer that capacity to relieve three very congested main lines, the west coast, the midland and the east coast. So we do really need HS2 even though it could be better and could deliver even greater benefit with a few important changes.

    • ‘Even the Transport Select Committee say “it is essential for the UK for HS2 to go ahead”.’

      No surprise there. The TSC is packed with HS2 supporters, such as Louise Ellman.

      “HS2 will deliver more train path capacity per £ billion than the upgrading of the west coast main line did.”

      The numbers to support that assertion, are nowhere to be seen.

  7. An even better solution is to use the technology for the 2 100 century. The Maglev technology and thereby the German Transrapid Maglev. Theirs new version TR09 is a very calm and soft solution what we found out as one of two lobby groups that visit the IABG testplant in Lathen Germany the summer 2911. We toke a 100 kilometre test ride at their 35 kilometre long test plant. We also observed the train passing by in the actual top speed 350 km/h 218 mph. Subjectively the noise from the nearby way with a speed limit of 70 km/h 44 mph.

    As the Maglev train reach about double the average speed as HSR it has much higher capacity than HSR. Mainly depending on short accelerations – and deceleration distances and a high top speed.

    A HSR do have a optimal top speed of 320 km/h 199 mph which have to be reduced to 250 km/h 155.5 mph as effect of increasing tearing and wearing of rail and track.

    For every single intermediate stop the Maglev extend the travelling time with extra four minutes. Normal HSR loose ten to quarter of an hour for every single stop.

    The Maglev do have much lower maintenance costs compared to HSR.

    The maintenance costs for HSR in 311 mph for train and track will be at a level of 34 percent of corresponding for the German HSR type ICE in 155.5 mph.

    The erection time will be much shorter as effect of prefabricated concrete segments which will be placed in position at in beforehand built pillars every 25 metre.

    Most of the problem with ordinary train do not exist re the Maglev. It has no catenary or conventional brakes low environmental impact as effect of no oil, no wearing and tearing as effect of contactfree operation. No heavy metal exhaust. No carbon – or brake dust etc.

    More relayable and available. Can be built to a cheaper cost. £16 bln for the 800 kilometre distance from London to Glasgow. Passing over the Pennines.

    Japan sais our Shinkansen is the world best HSR system depending on
    * Dedicated lines for passenger traffic.
    * Dedicated lines for HSR traffic.

    To get shorteast possible total travelling time. The Shinkansen have to frequent departure and close at common stations with ordinary train but on completely separated tracks. That means any compatibility is of less importance.

    • Two problems with maglev:
      -would have to be a totally separate network – couldn’t run trains onto the existing network

      • As you probable know the Japanese Shinkansen do have the best result re wheel on rail HSR. They have had no death since start of operation 1964. Each journey had an average delay of half a minute to one minute.

        The only HSR-system that have better result is the Shanghai Maglev train. The total daily delay is within seconds.

        Why Japan had that good result is basically two fundamenta.
        * Dedicated lines for passenger traffic.
        * Dedicated lines for HSR.
        To get shorteast total travel time the Shinkansen and ordinary have to call at common station but on completely separated tracks.

        To mix train with different speed do only minimize the capacity.
        To let HSR goes on existing network do only result in increased wearing and tearing as effect of different rail profile.
        The Maglev track can be alinged with existing high ways. Half the curve diametre compared to ordinary train and can manage inclination of 12.5 percent. The ground demand is just 2.1 m^2 pro lengthmetre track. The uplifted guideway have less demand than a 3 metre wide cycle lane.

  8. I thought HS2 was to form part of the European HS network via a link to HS1. There is no mention of Europe at all. It’s all about Brummies to Brentford and not Brummies to Barcelona..

    • I thought HS2 was to form part of the European HS network via a link to HS1

      It does that as well – you’ll have to speak to the article’s author about why he didn’t mention it?

  9. ” it is generally agreed that the country needs a new north-south railway to provide the capacity our growing country needs.”

    Yes, yes, but it is not generally agreed that this makes HS2 the right package to provide it. Here’s HS2 Plan B, a full-scheme alternative for comparison. I produced it because I thought HS2 was badly thought through.


    Unlike HS2, Plan B would start North-first. Stage One would halve today’s rail time for the forty miles between Manchester and Leeds and take half an hour out of centre-to-centre rail times between Liverpool to the west and Hull to the east: good for the N-S Divide.

    Unlike HS2, Plan B would have only one north-south main line. It would gather the Manchester-Leeds connector by M62 Jn.24 and continue south to the Eurostar and Thameslink interchange at St Pancras, stopping (unlike HS2) at East Midlands Airport and gathering the scheme’s east-west Midlands stage by M1 Jn.19.

    Plan B’s Midlands stage follows the M1 and M6 corridors to Birmingham via Coventry. By doing so it would avoid dragging Birmingham time-nearer to the London mega-magnet: bad for the North South Divide.

    Having a London destination at St Pancras means that a proportion of Plan B trains would run through to interchange with the London Crossrail at Farringdon (for the City and Canary Wharf) and with South London, Kent and Gatwick services via Blackfriars.

    Plan B does not include a northwards connector to the MML from the western end of the HS1 London tunnel, next door to St Pancras. The station already offers cross-patform interchanges to Eurostar.

  10. The utility of HS2 will be much better given improved connectivity with the existing network – at Calvert/Claydon with EWRL; at or near Birmingham International with the “Stonebridge Link”, etc.

  11. An article about how wonderful the £50bn/£150bn HS2 train line will be, written by an HS2 Ltd employee. There’s a surprise.



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