BAA have opened their consultation on AirTrack, the plan to link Heathrow into the South West Trains network, with services to Reading, Guildford and London Waterloo. I'd always had it down as a "we'll build it one day" type project, but it's starting to look like they might be serious.
The elements of this scheme are:There are all sorts of options and details in the brochure. The biggest surprise is BAA's "aspiration" to extend Heathrow Express services to Staines. The area is currently only served by stopping services to London, so this could be a big improvement if through journeys are allowed. They also say they're going to make the Airtrack tunnel overhead electrified, which will require dual voltage trains as the SWT network is all third rail.
Once this new rail infrastructure is in place, two trains per hour will operate in each direction to London Waterloo, Guildford and Reading. It is currently proposed that services will stop at: Clapham Junction, Richmond, Twickenham, Feltham, Woking, Chertsey, Wokingham, Bracknell, Staines Central and the new Staines High Street station.
- fitting out two platforms at the Terminal 5 station which has already been built tunnelling between Terminal 5 and Hithermoor
- constructing a new alignment across Stanwell moor and Staines moor
- forming a junction with the Windsor line
- building a new station at Staines High Street
- linking the Windsor line to the Virginia Water line in Staines Town Centre (the chord)
- remodelling the existing Staines station
Apart from the branch to Heathrow, the main bit of infrastructure needed is a new curve in Staines. Currently the line from Waterloo forks just west of Staines station into two branches, to Reading/Guildford and Windsow/Heathrow. The curve is needed for trains to get between those two branches. Here's a panorama of the area where it will be built, taken from the middle of the fork. The branches on the embankments either side.
Although this is right in the middle of Staines, the only thing that'll be overshadowed by the new line is the back of a shopping centre. This area is already cut off by the two existing embankments, so there are no pedestrians passing through. Although there are no buildings in the way, the line will cut through the car park ramp, and there are various options for how to replace it discussed in the consultation.