It will diverge from the North Auckland Line at Oakleigh, south of Whangārei, and serve Northport at Marsden Point.
In 1979, another proposal was made to establish a deepwater port at Marsden Point to export forestry products and the plan was resurrected.
The report was prepared by the Auckland firm of Kingston, Reynolds, Thom and Allardice, following recommendations of the Northland Forestry Port Study in 1979.
[10] In late 2008, ONTRACK served a notice of requirement to Whangarei District Council for the route's rail designation, seen as an important legal step towards the eventual line.
New Zealand First candidate and leader Winston Peters argued the line should be built to carry containers from NorthPort to Auckland.
On 31 August 2017, New Zealand First party leader Winston Peters announced a policy of relocating the Port of Auckland to Marsden Point by 2027.
[23] Peters had vowed in July that the building of the Marsden Point Branch at a cost of up to $1 billion was non-negotiable in any post–election coalition between NZ First and either National or Labour.
[25][26] The interim report of the feasibility study investigating moving the Port of Auckland to Northport was published in April 2019.
[28] A business case for the upgrade of the North Auckland Line and the Marsden Point Branch's construction was prepared by New Zealand Ministry of Transport and published May 2019.
[29] The business case found the total cost of the upgrade and Marsden Point line would be NZ$1.3 billion, with a benefit-cost ratio of 1.19 (assuming NorthPort's expansion goes ahead), meaning for every $1.00 spent there would be a return of $1.19.
[29] A KiwiRail arranged geotechnical survey carried out four test drills in December 2018 and January 2019 to check the land along the route.
At completion, a press conference was held by minister Shane Jones plus KiwiRail chairman Greg Miller and acting Chief Executive Todd Moyle; although "the numbers still had to be crunched" before any announcement on construction was made.
However, Northland Regional Land Transport Committee chairman Bill Rossiter suggested in February 2006 that passenger trains could be introduced (in the long term) for commuters between Ruakaka and Whangarei.