The project in question is the electrification and modernisation of the Great Western Main Line (GWML) from Maidenhead, west of London Paddington, to Oxford, Newbury, Bristol and Cardiff. Electrification from the junction with the spur to Heathrow Airport and Maidenhead is part of the Crossrail project, although Britain’s infrastructure manager Network Rail (NR) is responsible for both schemes.

A damning report by the National Audit Office (NAO) on November 9 revealed that the cost of the project has soared by 73% from £3.48bn as originally planned in 2013 to £5.58bn today and it will take between 18 and 36 months longer to complete. The electrification element has increased from £1.6bn to £2.8bn.

The government’s reaction is to defer some of the more challenging elements of the electrification project to save £146m - £165m. These include both routes into Bristol Temple Meads station where major track remodelling is planned and the section through the historic city of Bath Spa where special measures are required to lessen the impact of electrification. Other sections being deferred are Didcot to Oxford where track and station reconstruction is needed and the single-track Windsor and Henley branch lines.

To date, only electrification has only been completed on one section of the GWML: the four-track route from the west of Reading to the east of Didcot which is being used to test the new class 800 trains. Already the production of these trains has had to be modified to ensure the entire fleet is bi-mode rather than the original plan for a mixture of electric and bi-mode trains. Doubts have also been raised as to whether the trains will be powerful enough in diesel mode to match the timings of the 40-year diesel trains they will replace, let alone improve on them.

The delays and deferrals mean that the fleet of EMUs already being supplied by Bombardier for shorter-distance services to Oxford and Newbury are currently sitting in sidings for most of the day with little to do, and their deployment will need to be rethought as they will not be able to run to Windsor, Henley or Oxford. This in turn will have consequences for the redeployment of DMUs to other routes.

The NAO lists several reasons for the delays and cost overruns by both NR and the Department for Transport (DfT). According to the NAO, NR underestimated the cost of the project, the number of bridges which would require upgrading or reconstruction, the duration of the project, the cost of obtaining planning permission for the works, and it failed to plan and deliver the infrastructure programme. The DfT is criticised for failing to manage and plan the programme cohesively, and both organisations are accused of not integrating crucial elements into one programme.

The NAO says the electrification timetable was not based on a bottom-up understanding of what the works would involve. Had NR taken the trouble to consult with engineers involved in previous main line electrification projects, a lot of the mistakes could have been avoided. Unfortunately there is a tendency to dismiss former British Rail engineers on the grounds that the world has changed and things have to be done differently today.

Even now, insufficient thought appears to be given to trying to understand exactly what mistakes have been made, how they can be corrected, how costs can be reduced, and how the project can be brought back on track, rather than simply deferring key elements of the project, which will only achieve relatively small savings anyway.

Failure to reduce the cost of electrifying and modernising main lines and accelerate their implementation will seriously jeopardise the chances of any further electrification in Britain. Delays with the GWML, northwestern, and Scottish electrification schemes, have already resulted in work being halted to electrify the London - Sheffield Midland Main Line and the deferral of electrification west of Cardiff to Swansea.

It took a huge effort to get electrification back on the agenda in Britain. Railway privatisation in the 1990s followed by strong opposition from the DfT to even the idea of electrifying railways in the vain hope that some new form of powering trains would emerge caused a hiatus for nearly two decades. It was only when Lord Andrew Adonis was appointed secretary of state for transport in 2009 that electrification was taken seriously again, and he managed to push through the GWML project and electrification of the Liverpool - Manchester - Preston triangle.
NR and the DfT need to launch an in-depth investigation into what has gone wrong in order to understand clearly how electrification can be implemented in a timely and cost-effective manner, and help should be enlisted from other railways to discover best practice.

NR also urgently needs to rediscover its project management skills. In 2014, NR completed the £895m project to rebuild and expand Reading station, a major bottleneck on the GWML, on budget and one year ahead of schedule. If it can manage one large and complex project so well, why has it failed to manage the modernisation of the rest of the GWML?

The future of electrification in Britain is at stake, so there is no time to waste in rebuilding Britain’s electrification skills.