Electrification masts are in place on the brick viaduct near Castlefield Junction, Manchester.
Castlefield Junction to Ordsall Lane, Salford, is the first section of the line to be tackled.
Once that and the route as far as Newton-le-Willows is completed in 2013, TransPennine Express will be able to run new electric trains from Manchester Airport to Glasgow and Edinburgh via Parkside Junction, near Newton-le-Willows.
Ten new four-coach class 350 electric trains are to be ordered from Siemens to operate that service.
When the next section of the electrification to Liverpool is completed a year later, many more services will be run with electric trains, mainly using second-hand units from the south east of England.
The journey time between Liverpool and Manchester will be reduced from around 45 to 30 minutes. At the same time as electrification, the line is being upgraded for 90 mph running (from the existing 75).
Further electrification in the North West will see Huyton to Wigan (by 2014), Preston to Blackpool (by 2015) and Manchester Victoria to Preston (by 2016).
Network Rail map of the electrification area.
Information from Greater Manchester Transport Campaign. Email: transcamp at tiscali.co.uk
More information and another map: NR