Marshlink Options to Provide Additional Local Capacity

An hourly inter-regional service runs between Ashford and Brighton.  Although the route between Ore and Brighton is electrified, the 25-mile section of track between Ore and Ashford is un-electrified.  This means that the service is operated throughout by a small fleet (5 units) of 2 car diesel Class 171 trains:

These were built between 2002 – 2005, and are no longer in production.  Other similar units are operated across the national rail network e.g. on Scotrail and Cross-Country Trains.  Unfortunately the DfT ordered too few units for our local services, and also ordered 2 car units instead of 3 car ones.  The result is overcrowding on the Brighton – Ashford service, especially at peak periods, variously between Brighton – Eastbourne – Hastings & v.v.

Most other lines in Kent and Sussex are electrified with 750V DC third rail and use Class 377 electric units or variants thereof, which are configured in 3, 4 or 5 car units and which can work in combination up to 12 cars:

With relatively simple modification these trains can also draw power from overhead wires.

So what are the options to provide additional capacity locally?

  1. ‘Truncate’ the Brighton – Ashford service at Eastbourne or Hastings, and use more plentiful electric trains to the west.

The rail user groups strongly oppose this because it would mean that through passengers would have to change trains, and more generally this would almost certainly discourage them from making through journeys at all – this is the only east-west rail link between Kent and Sussex, and provides important connections at both ends especially onwards to Eurostar and HS1 services at Ashford.

This option would not even address all of the overcrowding issues.  It would go against regeneration plans which see the East Sussex – Kent corridor as a growth area.  It is also noted that other parallel road links are poor.

  1. Acquire more diesel units and or/reconfigure the existing Southern fleet

This is difficult, though not impossible.  The Class 171 units are no longer in production but are in service with a number of operators around the country.  Electrification projects and provision of new stock elsewhere could release additional diesel trains.

The release of just two 3 car units from elsewhere to Southern, and reconfiguration of the Southern fleet [which is shared with the Uckfield Line] from 4 or 2 cars into 3 cars, could resolve most of the overcrowding on the Brighton – Ashford service.

Alternatively Southern/GTR could acquire units of a different design – if it were minded to….

  1. Electrify the line between Ore and Ashford so that it can take standard Class 377 electric trains, and also potentially ‘Javelin’ high-speed trains in the future.

This is the preferred long-term option for rail user groups, either using 25KV AC overhead electric OR 750V DC third rail.  However at the present time, the national electrification programme is in trouble with cost over-runs and significant delay.  It is likely that the Hastings – Ashford line would have to join a long waiting list.

N.B. A third-rail option would be cheap, easy to install and quick, and would also be compatible with the system on surrounding lines, but currently there is an embargo on further third rail projects because this power source is seen as less efficient, and the long-term intention is to phase it out.

If the line is not electrified between Ore and Ashford, a High Speed service between Bexhill and London St Pancras might still be achievable using bi-mode electric/diesel Intercity Express Units – see BRAG’s Javelins v. Bi-modes paper.

  1. Modify a small number of Class 377s to ‘bi-mode’ by installing diesel engines.

This would provide additional capacity.  These could run under electrified power between Brighton and Hastings/Ore, then on diesel power to Ashford.  In mid-2015, DfT/Southern promised to investigate the possibility, but there has been no further progress to-date….

Other possible options include Battery Powered Trains or ‘hybrids’ which could recharge on the third-rail power between Brighton and Ore, and then use battery power on the section to Ashford.  However, this technology is in its infancy, and as yet is not proven.  Think how often and how long you have to recharge your mobile phone! Such trains are not in production, and such a development where they can run intensively on a daily basis and at high speeds, is some years away in our view.

Our other niggling doubts…..

We are often left asking ourselves if the DfT and train operator Southern GTR/actually WANT to pursue an innovative solution, or in the absence of electrification, would rather pursue the ‘lazy’ option of a truncation of the Brighton – Ashford service….. We note that –

  • Additional diesel trains would also incur additional leasing charges.
  • Lengthening the diesel fleet to 3 cars would require new berthing/refuelling facilities somewhere, as the yard at St Leonards Diesels can only accommodate 3×2 car trains.
  • Bi-mode trains would also incur will, effort and development costs.
  • The train operator doesn’t appear to want to expand its diesel fleet to include a different design.