Managing train service changes

Managing the changes to the Thameslink services timetable during the ten blockades took a lot of coordinated effort and pre-planning

Coordinating train service changes through blockades and possessions

In the early stages of design, to enable the redevelopment of the track around London Bridge and the station to be completely redeveloped, plans included eight major blockades of eight to ten days each over August Bank Holiday, Christmas and Easter from December 2012 through to December 2017. A further ten smaller scale sets of works were planned over other Bank Holidays;

A blockade is defined as a possession of elements of railway infrastructure that includes a normal working weekday. It excludes long possessions over a Bank Holiday weekend which could be dealt with under normal arrangements.

The initial proposals drafted in 2011 looked like:

The impacts on passengers and Train Operating Company (TOC) staff were going to be huge whichever way the works were planned. Following many reviews and discussions the plans ended up including six major blockades:

Changes between the November 2011 proposals and September 2012 plans were: –

  1. Extension of the August 2014 blockade to 9 days from the originally proposed 8 days.
  2. Extension of the December 2014 blockade to 16 days from the originally proposed 8 days.
  3. Removal of the August 2015 blockade. This was originally proposed to be 8 days.
  4. Re-dated Easter 2016 10-day blockade to August 2016 6-day blockade.
  5. Removal of the December 2016 blockade. This was originally proposed to last 10 days.

The main significant change made during the Programme was increasing the duration and scale of works for August 2017 Bank Holiday which was extended.

For each of the major blockades, timetable planners had to develop the most effective train services possible given the infrastructure available. Drivers and other train crew had to be consulted and then trained and briefed on any changes that impacted the routes, signalling etc. route learning for diversionary routes. Station teams had to be consulted, briefed and trained on changes that impacted train despatch, changes in retailing tickets, moves of gatelines, ticket offices, safety validations, hazard checks, risk assessments had to be planned and carried out. Communications to support staff and passengers were key.

Mitigations envisaged originally for train services were split into two categories; alterations to existing service patterns or diversion away from London Bridge

  1. Alterations to services could include:-
    1. Train lengthening (subject to stock utilisation and availability)
    2. Use of shuttle services
    3. Turnback at South Bermondsey
    4. Turnback at New Cross gate via the Up Sussex loop
    5. Transfer of Charing Cross services to Cannon Street and vice versa
    6. Stepping up (subject to resource availability)
    7. Use existing services into other London termini.
  2. Diversions could be:-
    1. Promote shift to High Speed 1 (HS1)
    2. Use of the East London line
    3. Use of the Docklands Light Railway (DLR)
    4. Use of Croydon Tramlink
    5. Diversions into Blackfriars bays
    6. Diversions into Victoria station
    7. Diversions via Crystal Palace or Streatham.


As covered in other case studies the idea of opening up and using the Waterloo International station platforms was also progressed.

Consideration was also given to train stabling; capacity at depots and best locations for the rolling stock during and after the blockades.

  1. Key challenges

  • Bringing all relevant parties together to discuss the plans and reach agreement.
  • Each party to understand the reasons for proposals and to be open minded on options.
  • Keeping sufficient train services operating whilst major redevelopments of stations and tracks take place.
  1. Recommendations for future projects

The following recommendations, based on the direct experiences of the Network Rail and the Train Operating Companies involved, will result in a more operationally focussed delivery of infrastructure changes:

  • Work together to understand each other’s viewpoints and reach compromises.
  • Involve design partners and operating experts whilst discussing options and planning blockades.
  • Do not necessarily accept plans that are quickest. Consider all options and transport modes to help passengers complete their journeys.

Case Study produced by Anne Clark, Network Rail Project Manager, April 2019.

Further information

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