Hyde Park Now-Warren Street to Victoria 1962-69

Warren Street to Victoria 1962-69

In the other posts covering the section of the Victoria Line that was opened in March 1969, the construction work at Oxford Circus, Green Park and Victoria tube stations was featured on individual merit, with Oxford Circus requiring two posts because of the complexities at that site. Everything was covering – prep work, tunnelling, piling, the Oxford Circus umbrella, etc. However there were of course other works to build this section of the line – and here its the line’s air shafts, its gradients and electrical supplies.

The Victoria Line’s air shafts in Central London

Some of the tube’s most unusual air shafts were built along the route of the Victoria Line and includes those at Great Titchfield Street and at Palace Street in Victoria. A number of the head house buildings on other parts of the line (for example Netherton Road, Pulross Road) have been modified or rebuilt since the construction of the line, however those at Coburg, Great Titchfield and Palace Streets remain as they were – somewhat inconspicuous shafts built within offices or new housing development.

In general one would not know there were air shafts to be had at these points! The only evidence would be the doors adjoining the pavement as well as basic notices saying this is an emergency exit please keep clear. That at Palace Street has no signs of any sort.

It does follow that if one is a resident at the properties where these shafts are, the existence of these air shafts will likely be known – here’s a report on the Pulford Street shaft and how its making people’s lives unbearable as the noise emanating from it has exceeded regulations at times.

Hyde Park Now-Warren Street to Victoria 1962-69

The Victoria Line’s air shaft in Palace Street, SW1.

The shaft in Palace Street is without a doubt the only other purpose built structure of its kind on the central section of the Victoria Line besides those at Great Titchfield and Coburg Streets.

Hyde Park Now-Warren Street to Victoria 1962-69

The old Dover Street tube station has long gone however its site is where the modern building is on the right next to The Clarence Inn. The Victoria Line’s air shaft cannot be seen as its sited at the rear of the building itself. It follows the other example nearby for the Jubilee Line, in that both are practically impossible to see from the street.

Hyde Park Now-Warren Street to Victoria 1962-69

The Victoria Line air shaft in Great Titchfield Street, incorporated as part of the local housing development. The structure’s design is adopted from the earlier one built at Coburg Street near Euston.

Great Titchfield Street is the only other purpose built shaft between on the section of line that opened in 1969 between Warren Street and Victoria itself. In other words we have those at Great Titchfield and Palace Streets. What it means is these are purpose built escape shafts and they have stairs in them for that purpose. The other shafts were adaptations at station sites or in the case of Gillingham Street a construction shaft converted to a vent shaft and they’re not really suited for public use in case of emergencies.

Victoria itself has several purpose built shafts. The first was built in Gillingham Street, work commenced in late 1963 to build a sixty foot deep shaft here and this work continued throughout 1964. This was a construction shaft to begin driving the tunnels northwards. The second is of course Palace Street was was built later in the construction programme.

Gillingham Street shaft is something of a mystery its not acknowledged officially. According to descriptions its said to be in Belgrave Road even though its described as Gillingham Street shaft. There is also a sub-station here which no doubt uses the shaft to supply the Victoria line. Google Streets in fact provides a substantial view of the electricity sub-station from Gillingham Street and its clear its been rebuilt. Its thanks to Google Streets I knew the exact location from which a photograph of both the ventilation shaft and substation could be got.

Hyde Park Now-Warren Street to Victoria 1962-69

The ventilation shaft (left) and substation just off Gillingham Street with the passport office behind.

Judging from my photograph I’m not sure the ventilation shaft itself has been rebuilt however the substation’s equipment was likely done at the same time as upgrades to Netherton Road and other important locations between 2009-2014.

Documents relating to Seeboard Powerlink (now EDF) give a complete list of all TFL’s sub stations and describes the Gillingham Street facility as being at 84 Eccleston Square – which is about right because the buildings are at the rear of those premises. Those premises belong to TfL (or did until recently.) Seeboard Powerlink had a 30 year PFI contract to provide supplies for the tube from 1998, however in 2012 TfL pulled out of that PFI contract.

It seems the electrical supply from Gillingham Street was one of the facilities the Queen was invited to inspect as part of her tour around Victoria tube station on the official opening day in 1969. For that purpose a temporary wooden walkway was laid over the top of the tracks from the southern end of the northbound platform. A machinery room and the reversing sidings were also included as part of that tour – the temporary walkway of course meant the Queen did not have to venture upon the tracks themselves! There’s more of this in the section to follow on the building of Victoria tube station.

Some people will point out there’s an air shaft at Moreton Street south of Victoria. Indeed there is this one however it was built as part of the Brixton extension.

Victoria Line gradients through the central section

Green Park tube station (Victoria Line) is the only one on the central section out of six stations (King’s Cross to Victoria) that employs the classical saw tooth gradient profile on the approach to the stations. Although the use of this method (first used on the Central London Railway) was intended to enable trains to accelerate and decelerate faster and though it has been used at the other Victoria Line stations outside of the central section (both towards Walthamstow and Brixton – with the exception of Finsbury Park) the saw tooth arrangement simply could not be employed on the central section at all – except very unusually at Green Park. The other five central core stations (Kings Cross, Euston, Warren Street, Oxford Circus and Victoria) are therefore all on either a rising or failing gradient.

As most will likely know by way of simple observation of especially the southbound platform King’s Cross, the line is on a falling gradient. This in fact continues through Euston as far as a point mid way towards Warren Street the line instead begins to rise. Although Warren Street has a classic 1 in 50 approach form the north, the line from here continues to climb as far as a point between Fitzroy Square and Great Titchfield Street where both lines take different gradients in order to cross each other – thus facilitating the switch from right to left hand running. From here to Oxford Circus the gradients for the north and southbound lines are different.

Hyde Park Now-Warren Street to Victoria 1962-69

On the up the gradient into Oxford Circus station. The ‘hump’ in the tracks at the bottom of the picture is because of the change from a rising gradient to a falling gradient.

Its why when one stands at the southbound platform at Oxford Circus the train can be seen coming up a gradient. That is because there is this overall climb upwards from Warren Street. However this changes to a falling gradient almost as soon as the train reaches the end of the tunnel and enters the platform area.

In comparison the northbound line itself, even though it is on a rising gradient, in fact continues to rise beyond Oxford Circus because it has to cross over the southbound line. This is evident if one walks from the Bakerloo across to the Victoria, the passageways rise gently from one to the other in order to accommodate the Victoria Line’s northbound rising gradient.

Hyde Park Now-Warren Street to Victoria 1962-69

The northbound tunnel climbs out of Oxford Circus station. Although the track seems quite level the fact the tunnel itself has a rise is evident enough.

The falling gradient just mentioned continues through Oxford Circus station (which has some of the steepest graded platforms on the entire line apart from Finsbury Park.) The falling gradient continues towards Berkeley Street before adopting the classic 1 in 50 sawtooth approach/descent into and out of Green Park station. The section approaching Victoria is invariably on a failing gradient and features some of the more severe gradients on the line (again that’s apart from Finsbury Park) and are as much as 1 in 40.

Hyde Park Now-Warren Street to Victoria 1962-69

Picture showing the 1 in 50 gradient into Victoria station. The view depicts work on the crossover just north of the station. Source: Twitter

Although the approach to the crossover north of Victoria station is a classic 1 in 50, the steep descent from Green Park makes the bottom of this descent and the rise up the 1 in 50 seem like a switchback to the more discerning traveller especially if the train has a clear run into the station. Like Oxford Circus, Victoria station is too on a falling gradient.

The rest of the stations to Brixton are all on the classic see saw arrangement (namely 1 in 50 approaches and level platform sections.)

The power supplies for the new line

Power supplies are something that’s rarely mentioned in terms of tube construction. One very unusual point about this aspect is London Underground previously had its own power stations at Lots Road and Greenwich and of course in order to supply the different tube lines a dedicated network of power cables had to be in place. That for the Victoria Line was no difference and it meant a dedicated 22kV power line was built from Lots Road to Cobourg Street which would be the main entry point for the entire line. Nine new substations were built (as well as Cobourg Street) at Forest Road, Seven Sisters, Manor House, Drayton Park, Cloudesley Road, Dover Street, Gillingham Street and Northumberland Park. Those at Drayton Park and Cobourg Street are the most instantly visible sites.

Hyde Park Now-Warren Street to Victoria 1962-69

Power supplies supervisor at Coburg Street in 1968 when the first stage of the line had been opened.

With the closure of Lots Road power station the distribution system has been changed somewhat. There is still a major entry point to the system at Lots Road (in view of its former strategic location as the main power entry point to the system) however this is now classified a BSP (Bulk Supply Point.) There are other BSPs that take in power from the main national grid at Neasden, Tower Hill, West Ham, Marylebone, Manor House, plus two other subsidiary BSPs at Acton Lane and Finchley

How the power is used is basically as follows. The main feed is 132kV, which is stepped down to both 22kV and 11kV. It is then stepped down to provide 630V/750V DC traction supplies, 400/600V signalling supplies, 400/230V for stations (inc lights) pumps, lifts, escalators etc, and also for the air compressors which operate the points and train stops.

People will know Cobourg Street was the original control centre for the entire line (as well as a substantial section of the Northern Line.) Control for these lines has now moved to Highgate (Northern) or Northumberland Park (Victoria.) Cobourg Street however still retains its air shaft and power supply, which is why it has a considerable substation at the rear of the premises. In fact it remains the main site for power supplies to the Victoria Line even though its no longer a strategic operating facility. What it means is the entire building consisting of large offices and facilities simply cannot be made redundant – thus TfL has had to rent out the office space.

One might wonder where the main control for the tube’s power supplies is sited these days. Its at Palestra (TfL’s huge office block opposite Southwark tube station) and this is where the new Power Control Room is sited. This of course oversees all the BSPs as well as distribution of power across the network and it also monitors supplies and ensures every part of the system is adequately supplied.

Will Coburg Street be decommissioned?

Well that’s a good question and one I’ve thought about. ATM Cobourg Street remains in use as a facility for electrical supplies and well as ventilation to the Victoria Line. The building itself is used as offices however since the removal of both the Northern and Victoria Line control rooms the premises can be considered surplus to requirements as its only in partial use.

In view of the HS2 works for Euston and the need for a new ventilation shaft in lieu of the old one in Melton Street, I wondered why Cobourg Street could not be used in lieu of a new TfL facility at Stephenson Way? I think the problem is Cobourg Street is just too far away to efficiently serve the complex network of ventilation tunnels to the tube beneath the main line station itself.

I have not seen any indication as to this however its possible the facilities at Cobourg Street could eventually be redundant and TfL will have a prime central location they can dispense of.

Next: The building of Victoria Station 1962-1969