Auckland Transport will be asked by its council parent to give high priority to a south-facing rail link from Manukau while also considering the cost of electrifying trains to Pukekohe.
The council's transport committee this week heard the organisation's board is to consider electrification costs to Pukekohe at its next meeting in a fortnight.
But after the Franklin and Papakura local boards urged a more direct rail link with Manukau, the committee also decided to ask Auckland Transport to give that high priority before electric trains start running in 2014.
Although the Government's existing $500 million electrification project is to stop at Papakura, committee member Christine Fletcher said an extension to Pukekohe was "the next logical step".
Mrs Fletcher, who is also a council appointee to the transport board, believed an existing order of 57 electric trains being built in Spain should be extended.
Although the cost of electrifying rail to Papakura was estimated at $115 million in 2008, and would normally be seen as the Government's responsibility, committee chairman Mike Lee noted that he and Mrs Fletcher had persuaded the transport board last month to save $50 million by scaling down the upgrade of Dominion Rd.
"So it's a matter of priority," he said.
The committee also decided council staff should do their own study, although in consultation with Auckland Transport and the local boards, on the costs and benefits of a south-facing link from Manukau in relation to other rail projects.
Councillor George Wood said an $81 million north-facing line to Manukau, built to feed into a new Manukau Institute of Technology campus, was not "giving anywhere near the level of service it could do to people living to the south".