Great Western electrification

Class 801
Great Western main line electrification hits key stage with work to commence at Bath
Published Mon, 2015-07-20 19:02

In the recent announcement that a number of Network Rail’s projects were to be deferred, one scheme that has survived and is seeing major work in hand is that of the electrification of the Great Western main line from Paddington to Bristol and Swansea (although the Welsh Secretary, Stephen Crabb, hinted on the BBC’s Sunday Politics Wales yesterday that completion to Swansea might not meet the original 2018 target.




Artist’s impression of the new Hitachi Class 801 Super Express in FGW livery. © Hitachi Rail Europe and licensed for reuse under the Creative Commons License
He said ‘Whether that happens in accordance with exactly the timetable that we want it to and we envisaged, I'm not here to say that that will be the case but, clearly, we're going to finish the project and it won't be too far out of the original timetable.’).
One factor in this may be that there is a commitment to acquire the rolling stock and, without the 25kV wires to operate them, a significant number of these new units will be sitting in sidings at vast expense. It is the potential introduction of these units, with the changed working required to operate them, that has led to the ongoing dispute between First Great Western and the unions. This resulted in a two-day strike earlier in the month with the threat of further industrial action to come.
The section of the ex-GW main line from just west of Hayes & Harlington into London Paddington is already electrified as part of the Heathrow Express link and Crossrail will see the 25kV wires extended to Maidenhead and to Reading. In July 2009 the then Labour government announced that the main line from Paddington to Bristol via Swindon, from Swindon to Swansea (via the Severn Tunnel), the link from Bristol Parkway to Bristol Temple Meads and the line from Didcot to Oxford would all be electrified. Work would also be undertaken to electrify the Berks & Hants route from Reading to Newbury and the Thames Valley branches to Henley, Marlow and Reading.
Following the 2010 general election, the Transport Secretary of the coalition government put a hold on the project pending a review and, in November of that year, Philip Hammond gave the go-ahead for work to start on the Reading-Oxford/Newbury routes. This was followed in March 2011 by confirmation that the electrification of the lines from Didcot to Bristol and Swindon to Cardiff along with the Temple Meads to Parkway link in Bristol would also proceed. This was further amended in July 2012 when the extension from Cardiff to Swansea was also approved. Electrification of the branches from Cardiff is covered by a separate project.
The project requires the renovation and operation enhancement of a number of stations that serve the route. At Bristol Temple Meads, the electrified services will terminate in the Digby Wyatt extension to Brunel’s original train shed. At present this is occupied by a car park and Bristol power box, which opened in 1970 and which currently blocks rail access to the building, will be demolished. Bristol Parkway, which has had a new platform on the up side since 2007 will gain a further platform on the down side. Additional capacity will be introduced at Cardiff Central through the construction of a bay platform at the west to serve trains to Maesteg and two new through platforms on the south side of the station; this will take the number of platforms at Cardiff Central up from the present five to 10. Work has also been undertaken or planned at Newport, Paddington, Swansea, Severn Tunnel Junction and Port Talbot Parkway.
Prior to the final go-ahead to GW electrification, Reading station was already subject to a major reconfiguration project. Announced in September 2008 and estimated to cost £400 million (the price had risen to £800 million by 2014), the scheme involved the construction of five new platforms at the station, a new entrance at the north as well as significant reconfiguration of the tracks to the east and west of the station with under- and over-passes.
In order to operate the new long-distance services, replacements for the ageing InterCity 125s have been ordered from Hitachi. These are the new Class 800/801 units currently under construction for operation on the East Coast and Great Western main lines. The Class 800 — of which there 32 nine-car and 27 five-car sets on order — are electro-diesels, designed to operate primarily using the 25kV overhead but with an auxiliary diesel engines for use on non-electrified lines, including the Great Western main lines beyond Bristol to Exeter and Penzance. The Great Western main line is scheduled to receive 19 of the nine-car and 17 of the five car sets. The Class 801 units are simple EMUs of which 51 nine-car and 12 five-car sets are due to be delivered again for operation on the East Coast and Great Western routes. Of these 21 of the nine-car units are allocated to the Great Western. The servicing of the new units is to be undertaken at three new depots: North Pole in London (where the Eurostar units were originally housed and serviced), Filton Triangle (at Stoke Gifford to the east of Bristol) and at Maliphant sidings in Swansea.
Stock for the suburban services into London Paddington will comprise Class 387 four-car EMUs transferred from Thameslink along with Class 365s transferred from the Great Northern section. The existing Class 165/166 units that are used on the services are to be transferred to Bristol and the south-west for use on non-electrified services.
One of the challenges faced by the engineers planning the route’s electrification is the historic nature of the Great Western main line. With much dating back to the original work undertaken by Isambard Kingdom Brunel when the line was constructed in the late 1830s, there is a requirement to ensure that the new work does not impact upon the listed nature of many of the route’s structures. That electrification of historic structures can be sympathetically achieved has been demonstrated by the work in electrifying the East Coast main line over the Royal Border Bridge at Berwick. With work starting on the high-profile section of line through Box Tunnel and Sydney Gardens at Bath, it will be interesting to see how Network Rail’s engineers are able to integrate the infrastructure required for the 25kV into these sensitive locations.
Although it may that the date for completion to Swansea has slipped slightly; nonetheless, it looks as though the bulk of the electrification of the Grew Western main line is progressing towards completion in 2017/18.