Increasing capacity on a railway is not just about running more (or longer) trains. If the associated stations can’t cope with the increased passenger numbers, then remedial action is needed. Here, we look at major upgrades at Underground stations in general and at Holborn in particular.

Shut ’em out

Congestion at the station – photo from consultation document

If too many people are attempting to enter a station then the short-term solution is simple, if not wholly desirable. You restrict access to it. It is not often that this is necessary at a surface-level station. Usually, it is restricted to exceptional circumstances such as passengers arriving after the end of a major event (such as a sporting fixture or concert) or a strike involving some rail services but not others.

In the case of stations where the platforms are located underground, the danger of too many people wishing to enter the station can be mitigated by restricting flow through the inward ticket gates. This is not ideal and critics may well complain that this is a classic case of reducing the risk for which the operator is responsible (on his premises) by means of passing it onto someone else, rather than eliminating the source of the problem.

Dear departed

If too many people are attempting to exit a station then the situation can be more serious. Particularly if it cannot be resolved by mitigating measures such as ensuring the direction of travel on escalators is prioritised for passengers wishing to exit. It is rare that a build-up of arriving passengers is sufficient to cause a safety risk but, when it does, the only real option available is to have trains non-stopping at that station. With Underground stations in the centre of London generally located within walking distance of the next station, this is viable, albeit unpopular.

It is not hard to envisage the possible consequences of a station being temporarily closed (either totally or for passengers wishing to enter) in the centre of London at busy times. Many passengers will naturally head for the nearest adjacent station on the same Tube line. This station then becomes much busier than usual and is then itself at risk of closure. The real danger is thus the triggering of a chain reaction in which a number of stations are forced to close. When signs of this happening begin to emerge, or when experience tells line controllers that it is likely if the situation is left unchecked, staff are then faced with the unenviable task of closing a whole section of line.

Justifying Bank station upgrade

Northern line stations within a mile of Bank

It was the fear of such a chain reaction that led to the need to make Bank Underground station fit for the future and prompted the half a billion pound capacity upgrade now currently underway. When Bank is forced to close, this puts considerable pressure on the entire Bank branch of the Northern line as potential passengers walk to Moorgate or London Bridge instead. It can be the case that a closure at Bank Underground station results in a closure of London Bridge Underground station just 13 minutes later. Left unchecked, and assuming passenger numbers revert to rising annually as they have done in past years, this meant that without the capacity upgrade we could have seen a situation where the entire Bank branch of the Northern line would be forced to close at short notice simply because of a problem at one busy station.

Almost worst case scenario

The almost-as-bad-as-it-gets case is an Underground interchange station where there is interchange with two or more deep-level lines. This is, of course, the situation at Bank. Another station notorious for problems is Oxford Circus, although in contrast Green Park, with its numerous long connecting passages and about half the number of passengers as Oxford Circus, appears to rarely cause any problems – something that might well change in future.

Worst of all

There is actually an even worse case than the interchange situation described above. This is where there is a frequent service on one deep-level Underground line built to National Rail gauge with high-capacity trains interchanging with a small traditional tube-sized line of limited capacity. This will be the situation at Bond Street and Tottenham Court Road when the Elizabeth line opens. These two stations were already suffering from overcrowding. They are being rebuilt as part of Crossrail, but would likely have been rebuilt anyway as part of a London Underground scheme, had Crossrail not have gone ahead. At both of these stations the London Underground side of the work is now complete. The recent opening of the new Bond Street entrance has been covered excellently by IanVisits (mainly photos) and Geofftech (video).

The interchange that isn’t

Whilst modelling showed that Bond St and Tottenham Court Road would be capable of managing the expected passengers once the Elizabeth line opens, it was clear that a combined Oxford Circus/Bond St (Crossrail) east entrance could not. If you have ever wondered why the Elizabeth line has no sub-surface interchange with the Victoria line at Oxford Circus despite the eastern ends of the Bond Street platforms being tantalisingly close, this is your answer. As the Victoria line at Oxford Circus is never likely to be able to handle the expected numbers of people that would board if there were direct access from the Bond St Crossrail platforms, it appears the two stations will never be linked with publicly accessible passages below ground.

The clever interchange

How Farringdon will appear on a future tube map

Also on the Elizabeth line is Farringdon, which will not only be an interchange with Thameslink, but also with the Sub-Surface lines (Circle, Hammersmith & City and Metropolitan). Here, quite cleverly, some of the problems of interchange with existing Underground lines are dissipated by having the Elizabeth line station interchange with two Underground stations rather than one.

Why station capacity upgrades are rare

Given the obvious benefits of increasing station capacity that are close to their passenger limit, you might expect there to be an intensive and ongoing programme of upgrades. In fact, they are few and far between. The reason for this is simple: they are typically very, very expensive.

Given the history of London and the Tube network, the stations in question tend to be located at the most awkward places to carry out extensive construction works. Additionally, these places tend to be where land costs are extremely high. Such works therefore only tend to take place where there is a dire necessity – or a significant third-party contribution towards the cost of such works.

The numbers game

To put rough numbers into play, the cost of Bank Station Capacity Upgrade will be well over half a billion pounds – as will the cost of Victoria Station Capacity Upgrade. In neither case is this even a full upgrade, in each case focusing on one particular line (Northern line and Victoria line respectively). At Victoria, there was once a plan to complete the job and improve the situation for District and Circle line passengers, but that plan seems to have disappeared. Perhaps the plan is to wait until Crossrail 2 and complete the job as part of that project.

Camden – the only other upgrade in town

The planned upgrade at Camden Town, in comparison, would appear to be relatively cheap at a mere quarter of a billion pounds. As the current Camden Town plan would appear to be relatively simple, as these things go, and not in the centre of London where land prices are much more expensive, this would suggest that £250 million is the minimum start point for any decent deep Tube station upgrade that involves creating a completely new route to and from the platforms.

Why Holborn?

Holborn station was recently the subject of a consultation on improving station capacity. An obvious question is: why is Holborn next? To understand that, we must first understand the station’s history.

History and the previous awfulness of Holborn

As is often the case with old interchange underground stations in central London, the unsatisfactory nature of Holborn station stems from its historical development. First on the scene was the Central London Railway, forerunner of the Central line, who in 1900, as part of the original railway, opened British Museum station around 100 yards to the west of the current Holborn station.

The Great Northern, Piccadilly and Brompton Railway, forerunner of the Piccadilly line, opened their station in 1906. Due to complexities in the amalgamation of two tube schemes separately authorised by Parliament, the station was complicated by the contemporary building of a near-useless short branch to Aldwych necessitating additional platforms at Holborn and having the main northbound and southbound platforms on different levels.

Original platforms at Holborn. Diagram by David Cane used under Create Commons Licence

The unsatisfactory nature of the two stations, Holborn and British Museum, reliant on lifts and a short street walk for interchange between the two lines served, was quickly recognised and plans prepared to do something about it. Partly due to the intervention of the First World War, it was not until the early 1930s that this happened. As the combined station had to be located at the intersection of the lines, it was clear that it was the Central London Railway that had its station in the ‘wrong’ place.

The junction of Kingsway and High Holborn was the obvious place where a combined interchange station for the current day Central and Piccadilly lines should be. This may seem obvious now, but we can perhaps forgive the line’s early planners for not coming to the same conclusion, as it certainly wasn’t obvious until at least ten years after the latter line opened. Prior to then, Kingsway had not been built. The present-day station is located at the northern end of what was then a notorious slum area.

A catalyst for economic development

Holborn area with tube station marked

Whilst the general value of its location may have improved, Holborn is still really too far east to be considered part of the West End, but too far west to be considered the heart of the City and the current lack of capacity at the station is clearly hindering the economic development of the surrounding area. Marketed as ‘Midtown’, or, worse still, ‘Bee Midtown‘, a not universally-popular epithet, the local business district has done much over the past few years to highlight how the lack of a fit-for-purpose Tube station at Holborn has held back the development in the area. This applies particularly to the north of High Holborn and it is a considerable walk (by central London standards) from Theobald’s Road, a fairly major traffic artery, to any Tube station. Worse still that Tube station may be shut due to overcrowding.

It is pertinent to note that an early plan to have a Crossrail station at Holborn was abandoned. In reality, it would have been too close to Tottenham Court Road station to be really worthwhile. It would have restricted the alignment (bearing in mind that sub-surface Crossrail stations have to be straight and level). It would also have added considerable expense and may have put the entire project at risk. At the end of the day, it just wasn’t a good business case. Whilst a station on the scale of the Elizabeth line could not be justified, however, an improvement of the existing Holborn station could.

Stations nearby

Another answer to the priority given to Holborn is the fact that Tube station upgrades are judged not only on the local need but the overall consequential effect of not upgrading. On the Piccadilly line, Holborn station is flanked on either side by Zone 1 stations with lifts. Southbound, the next station beyond the adjacent station (Covent Garden) is Leicester Square which operates at capacity during evening peak hours when tourists and home-going commuters push the station to the limit. The saving grace with Leicester Square is that Charing Cross (for the Northern line) and Piccadilly Circus (for the Piccadilly line) are not far away. Clearly, one would not want to get to the situation where closing Holborn to inbound passengers forced the subsequent closure of Piccadilly Circus station.

Why Now?

According to a presentation to Camden council in 2013, the construction at Holborn was due to commence in 2018 in advance of the Camden Town station upgrade. So, what has caused the Holborn Station Upgrade to be delayed?

The answer is that the station work is closely linked to the Deep Tube Programme (DTP, formerly known as New Tube for London). Although the station work is not part of the DTP scheme, the DTP scheme is completely dependent on it. This is partly because the planned rise in frequency of the Piccadilly line (from 24 to 33tph) would mean that even having Holborn as an interchange-and-exit-only station would be unsustainable. It is also because the Deep Tube Programme (which includes the Piccadilly and Central lines – both of which serve Holborn station) needs additional power supply in central London. Supplying the considerable amount of extra power required would be much easier and much cheaper if done as part of a station upgrade programme.

An alignment

The current plans at Holborn would result in a new Tube entrance being built and in use by 2024, followed by refurbishment and enhancement of the existing tube entrance in 2027. The refurbishment would mean the existing Tube entrance would be closed for three years whilst the work was done.

Modified diagram from Business Plan

According to the latest TfL draft Business plan, the first new train on the Piccadilly line is due to enter service in 2023. If this is anything like the introduction of 2009 Tube Stock on the Victoria line, this means that one train will be in service for a round trip starting around 10.00pm on Monday-Thursday nights. The current rate of introduction of Class 345 stock on TfL Rail shows how painfully slow initial introduction can be and it could easily take a year or two to replace the 87 6-car trains now operating the service (actually 175 3-car trains, coupled together as a pair in service).

At a recent London Assembly Transport Committee meeting, TfL’s Director of Strategy & Service Development, David Hughes, stated that the existing Piccadilly line trains were due for replacement ‘in seven or eight years time’. That would take us to 2024-25. Allow another two years for the additional trains to be brought into service ready for 33tph and for Platform Edge Doors to be fitted along most of the line (not Rayners Lane – Uxbridge, shared with the Metropolitan line, obviously) and 2027 seems a reasonable completion date for the Piccadilly line upgrade – the same year as works are due to be complete at Holborn.

The solution

Again, to understand how Holborn must be rebuilt, one must first understand the work that was carried out when it was rebuilt before. Then, the Central London Railway platforms at British Museum needed to be replaced with ones further to the east and these new platforms needed to be linked into the ‘Piccadilly’ railway station at Holborn. In addition, the lifts at Holborn needed to be replaced with a suitable number of escalators. Unusually, Holborn was rebuilt with an escalator shaft with four escalators within it. This was unusual because normally the economics of tunnelling meant that beyond three it was better to dig two separate shafts.

Unfortunately, the Central London Railway had been built beneath the streets with the running tunnels located next to each other, as was the normal practice for Tube lines. Consequently, adjacent platforms connecting on the level with interconnecting passages was not possible for the ‘Central’ platforms and the platforms had to be built on the outside of the running lines. This, unfortunately, meant that same-level interchange was not possible between any of the four main platforms at Holborn station. Today, this scenario potentially complicates any attempt to build a second entrance to the station.

Worse still, the 1930s Holborn station seems to have been designed in an era where the science of understanding passenger flow wasn’t exactly mature. Having all the escalators together and requiring interchanging passengers (for whom the new station was supposedly built) to pass through the landing at the base of the escalators means that all passengers have to pass through this crowded area.

The plans

Destinations of people leaving Holborn station

In essence, to sort out Holborn station TfL wants to build a new station entrance in Proctor Street, next to Red Lion Square. Proctor Street is currently a wide, one-way street and TfL propose to reduce the width of the road to enable a modern station entrance to be built. Apart from the obvious benefit of not having to acquire land, two attractive features of the scheme are that it manages to avoid being located in the multitude of conservation areas surrounding Holborn station and that it is to the north of High Holborn, where future demand is expected to be highest and where there is the greatest requirement to stimulate business growth.

Proposals from consultation document

The issue of avoiding conservation areas is a big one – and one that the consultation team at TfL are quite open about. The Crossrail 2 team also take this into account when choosing sites for station entrances. It makes the planning process easier to get through.

Another obvious point is that if you built an Underground station entrance across approximately half the width of the road, it is going to have an impact on traffic (including buses). Clearly, the traffic measures adopted are going to be integral to the success of the scheme as a whole and a later consultation will cover this.

3D model of proposals

A side effect of choosing a station entrance located in the current roadway in Proctor Street is that there can be no oversite development. Whilst this is a disadvantage as it means that costs cannot be offset by the sale of the right to build above the station, this does at least simplfy the planning process.

Indicative sketch of Proctor Street entrance

The new electricity substation would be located in the basement of the new station entrance. From street level, there would be two escalators and a wide set of stairs to the ticket hall and three sets of escalators down to the platforms. Surprisingly, there will not be any lifts. It seems that there is no requirement for these to be present at every entrance to a rebuilt station and it will be easier and cheaper to reuse the original lift shafts at the original entrance to the station for this purpose.

Reusing the Aldwych platform

Upgrading the station will be costly, but it would be even more so were it not for the intention to undertake a creative bit of historical recycling – the plan is to re-purpose one of the former Aldwych platforms. Unfortunately this is the through platform – the only way for trains to be routed down the still-extant branch line. Consequently the Aldwych branch, no longer in passenger use but still used for filming, will be permanently severed from the rest of the Tube network. Piccadilly line crayonistas please take note.

Undoubtedly, the use of the Aldwych platform will arouse emotions, including sadness that this heritage feature will disappear. Nonetheless, others will be pleased to see old infrastructure being used imaginatively for a new purpose and look forward to a heritage area of a former Tube line becoming accessible to the travelling public. It is early days yet and it remains to be seen what plans will be made to acknowledge and include that heritage in the updated station. There is talk, however, of the platform tiling being retained.

Making a better entrance on Kingsway

Under the current plans, the new Holborn station entrance in Proctor Street will open in 2024. This will enable the existing station entrance to close for three years for improvement work. With the new Proctor Street entrance it is less important for the current station building to have an entrance directly onto High Holborn, so the current, restricted, entrance will be blocked off and all access will be to and from the existing Kingsway side. Lifts will be reinstated in the original lift shafts to make the station fully accessible – albeit only from one entrance. A rather unsatisfactory current feature that sees a fire exit from a nearby office leading into the Tube station ticket hall will also be addressed. The fire exit route will be rerouted to be completely independent of the Tube station.

What the consultation is really about

Apart from permanent road traffic issues after opening, it would seem that there really would be few reasons for people or organisations to object to the principle of the scheme as opposed to the manner and inconvenience of construction. Planning applications of this nature normally raise a host of objectors but many are actually in favour of the scheme as a whole but are forced to go through the formality of objecting to ensure that their particular issues of concern are addressed by the planning inspector. For example, it is common to see local councils lodge an objection that generally starts ‘whilst we strongly support the scheme in principle, we object to the proposals in its current form because…’.

Whilst the TfL Transport and Works Act team involved with this project must never take anything for granted, it appears that the biggest concern is to satisfy those who believe they will be adversely affected during construction. Similarly, that the work can be carried out without causing either general traffic chaos or undue problems to certain individuals such as the loss of access to private off-street parking.

The spoiler

There is a lot of spoil to be removed and the only realistic option is by lorry – and, of course, almost certainly particle-emitting diesel lorries at that, although one wonders whether the temptation to revive an early Crossrail plan to remove spoil via the old tram tunnel and nearby post office railway at least crossed TfL’s mind again. More seriously, Camden Council will have introduced their Tottenham Court Road scheme by the time construction begins, eliminating through traffic (except buses and cycles) from Tottenham Court Road. Oxford Street is expected to be fully pedestrianised by then. The rebuilding of Euston station as part of HS2 will likely be taking place less than a mile away is going to cause further problems that will ripple over a large area. Of particular potential concern is Crossrail 2. If this scheme goes ahead that will mean major works in nearby Shaftesbury Avenue as Tottenham Court Road station gets enlarged once more.

And next on the Piccadilly line?

In central London the Piccadilly line suffers from a combination of unmet heavy demand and stations operating at capacity. It is clear that to fully take advantage of a proposed increase in frequency from 24tph today (the absolute maximum achievable) to 33tph in future means various station issues along the line need to be addressed. Holborn is merely the first and most crucial of these. After Holborn, TfL’s focus is expected to turn other central stations. Covent Garden, still relying on lifts despite huge modern day footfall, is probably that next station that will urgently need addressing.

The next station westbound from Covent Garden, Leicester Square, has for years been restricted by its limited access. It would appear from the anecdotal evidence that passengers unable to use the station simply walk to nearby Piccadilly Circus (for the Piccadilly line) or Tottenham Court Road for the Northern line. This station too is starting to appear on TfL’s radar for station upgrades.

Beyond Leicester Square is Piccadilly Circus. An upgrade here is going to be problematic as land prices are high and potential worksites limited. Nevertheless, if the Piccadilly line service is increased to 33tph and the Bakerloo line is also increased to that, or higher, frequency in a post-Lewisham-extension world, it would be hard to see how the issue of capacity at this flagship station could be avoided. By the time the Deep Tube Programme delivers the new Piccadilly line trains, Piccadilly Circus station will have operated with its current footprint for over 100 years – an era when horse-drawn transport had not entirely disappeared from central London streets.

Incredibly, TfL are even thinking that they may have to upgrade Green Park yet again. The park by the station has seen workings for the Victoria line, the Jubilee line (phase 1), the Jubilee Line Extension and step-free access with a new entrance to the park. Certainly, if the future moving walkways (aka travelators) between the Northern and Central lines at Bank station are a success, then Green Park station is an obvious location where something similar could be considered.

To the north of Holborn station is Russell Square – another of those few Zone 1 stations with only lifts and an emergency staircase for access to the platforms. Whilst there is no inkling of any plans to change this, it does seem hard to envisage how this surprisingly-busy station, popular with local hotel customers, could continue as it is after completion of the Deep Tube Programme.

Ring-fenced

With the TfL budget being squeezed one has to be a bit sceptical about any future scheme. Currently, the big scheme in progress is the resignalling of the Sub-Surface Railway. That has to go ahead because without it the benefits of higher frequency on those lines cannot be realised. The Deep Tube Programme has to go ahead in some form because Tube trains don’t last forever and there eventually comes a point at which it is more cost-effective to have new trains rather than soldier on with the old ones.

If the Deep Tube Programme is to deliver a better more-frequent Piccadilly (and Central) line then Holborn station capacity upgrade is essential. The challenge will not be finding the money, or even the engineering, but finding a way of building it without causing disruption over a considerable area of central London.