KiwiRail has awarded a major multimillion-dollar contract for Auckland's rail electrification to a joint New Zealand and Australian consortium.
Hawkins Infrastructure and Australia's Laing O'Rourke have been given the $80 million contract to build the overhead electrical wires for the network.
The lines will cover 80km of rail corridor from Papakura on the southern line and from Swanson on the western line.
The Onehunga and Manukau branch lines are also included in the upgrade.
The system will be connected to the national grid via two independent connections at Penrose and Southdown.
KiwiRail says it will use less than 1% of Auckland's electricity capacity.
Masts will begin appearing towards the end of this year, beginning with Otahuhu working towards Britomart and will be completed by 2013.
Another component of the electrification, a $90 million upgrade to signalling systems on the network was awarded earlier this year to Westinghouse Rail.
The tender process to buy 114 electric trains to run on the network is continuing.