Auckland Transport is backing a finding that an airport rail loop would provide higher long-term benefits than other transport options for the region's southwestern sector.
The board of the council-controlled organisation yesterday gave its approval for a multi-agency study to progress to a detailed scheme assessment and business case for providing airport rail links from both central Auckland and Manukau.
These are costed in the draft Auckland Plan at $1.18 billion and could not be built until a $2.4 billion central city tunnel, which the Government has yet to be persuaded to support, provides the dead-end Britomart station with much-needed extra capacity.
The 30-year plan does not envisage completing an airport rail loop until 2040 - despite an election promise by Auckland Mayor Len Brown to provide one by about 2020.
But a report from the southwestern sector study - which was conducted for the Transport Agency, KiwiRail and the airport company as well as Auckland Transport and its council parent - says planning provisions for future links must be made soon.