With HS2 now to be tunnelled through Ealing, why not use the surface rail corridor to solve a number of other problems?

2 May, 2013

On 23rd April 2013, HS2 Ltd proposed a new 9km tunnel for the section of HS2 between North Acton and Northolt. The original plan was to use the largely disused right-of-way of what was once the Great Western Railway’s main line from Paddington to Birmingham, on the surface. With the need to have a larger gauge to accommodate European-standard high-speed train designs, this meant rebuilding several road bridges, including those at Hanger Lane Gyratory (where the North Circular Road joins the A40). The expected traffic disruption from the construction work at this location was a critical factor for those campaigning in favour of a tunnel solution.

Nowhere else does the Phase 1 HS2 scheme use a disused rail alignment with this kind of bridge constraint. So  nowhere else is this a relevant argument for HS2 to be placed in tunnel. Without the need for rebuilding the Hanger Lane Gyratory, HS2 Ltd says that the tunnel solution – in this instance – will actually be quicker to build by some 15 months and cost no more than the surface route. The local community and stakeholders will have the opportunity for their views to be taken further into account as part of a consultation on the preferred option in coming months.

There is, however, a much wider planning opportunity to be considered. The capacity of the rail network through West London – even with the planned HS2 route – is inadequate. There are two distinct problems:

1.  For HS2 itself, the Old Oak Common – Ruislip section lies between two sets of diverging junctions, at its eastern and western ends. From the east, this section of HS2 will have to accommodate traffic both from Euston and from HS1, two routes which conjoin at Old Oak Common. Both sets of traffic then have to share the same tracks as far as Ruislip where the route divides, with the main line continuing to the Midlands/the North and the planned spur onto Heathrow heading southwards. So a direct service between say Paris and Heathrow that could be accommodated by these connections would need to operate over the same tracks as a London – Glasgow HS2 service. In the long run, this will be a bottleneck.

2.  Meanwhile, the Great Western Main Line between airport Junction (where the Heathrow Express services join the main line) and Paddington has been identified by Network Rail as one of three long term capacity constraint problems yet to be resolved on its south east England network. This section of route has to accommodate the new Crossrail services as well as a substantial freight flow and long distance passenger service – and whatever services are operated to Heathrow in future.

Behind these headline network capacity constraints, lie some serious problems that could be expensive to resolve. One is the difficulty of retaining the fast journey time achieved by Heathrow Express once Crossrail starts operation (current plans would see journey times extended by perhaps ten minutes or so). The other is that the previous HS2 Ltd decision to tunnel the Northolt – Ruislip section of HS2 (to which the Old Oak Common – Northolt section will be conjoined) may add to the costs and difficulty of achieving the planned Phase 2 connection from HS2 into Heathrow.

The recent decision on tunnelling provides the opportunity to tackle all of these problems.. The proposition is simple. At Old Oak Common, the lines from HS1 need to be given a connection westwards to a pair of surface lines. These would operate at normal line speed (perhaps a maximum of 110 mile/h) over the surface corridor previously earmarked for the HS2 route. These lines would not offer enlarged European track gauge as HS2 requires: in effect this would be a double track re-instatement as far as the junction with the Chiltern lines at Northolt where a junction would be made. The connection to Heathrow could be made at Northolt or at West Ruislip as originally intended but from a surface rather than a tunnelled route. There would be no intermediate stations.

This would allow the following services to be operated, using the HS1 – HS2 connection but without taking up highly valuable train paths over the short critical section of HS2 through Ruislip and Old Oak Common:

  • A Cross London extension of the Southeastern high-speed services in Kent to any of the places served by the Chiltern route (for example: Oxford/Banbury – Bicester/Aylesbury – Princes Risborough – High Wycombe – Beaconsfield – Old Oak Common – Stratford – Ebbsfleet – Ashford – Dover/Canterbury) once Chiltern electrification is complete as foreshadowed  in the 2020s
  • Cross London services from Kent to Heathrow and onwards to Great Western Main Line destinations using the new Heathrow Western Access connection.
  • Amsterdam/Frankfurt/Brussels/Paris/Lille – Stratford – Heathrow services

The benefits of this proposal (which simply adds 9km of surface route track re-instatement to the newly revised HS2 plan) are:

  1. A significant addition to the value and role of Old Oak Common as an interchange
  2. The creation of a new fast connection between Heathrow and Stratford
  3. Relief of the pressures on the Great Western Main Line as well as on HS2 on the western approaches to central London
  4. Safeguarding of a direct connection between the South West of England and South Wales and the European high-speed rail network.
  5. Creation of a direct fast connection from the Chilterns to

(i)  to European high-speed services

(ii)  to Stratford for Canary Wharf commuters and direct connections throughout Essex and East Anglia

(iii) via a single interchange, rail connection to Heathrow Airport

(iv)  across London to destinations in Kent.

We believe that this concept should be worked up and is worth referencing in the planned consultation. It cannot be right to ignore the possible wider benefits this development would bring, facilitated by the decision to prefer a tunnelled section of route for HS2 through Ealing.