It welcomed the Budget announcement, saying the facility would be both regionally and nationally strategic infrastructure.
"The concept remains part of Northport's Vision for Growth. If built it will represent a massive win for both Northland and New Zealand as a whole, helping to diversify the economy and generating more than 400 full-time, meaningful jobs," the port company said in a statement.
Work on the physical and operational feasibility of this national infrastructure asset had already been completed, it said.
Ports of Auckland, which previous studies have suggested has a limited lifespan in the city's CBD, said it could not comment as port location was a matter for central and local government. The port is owned by Auckland Council.
Though no detail was available in the Budget, it seems likely the Government intends to continue the work of consultancy Sapere which in a 2020 Ministry of Transport-commissioned study recommended Manukau as the best option for an alternative port for Auckland.
New Zealand Shipping Federation executive director John Harbord welcomed the Government attention to ports, saying the future of both international and coastal shipping required ongoing evolution in port structure and the way ports interacted.
"Certainly new port infrastructure is a good thing but we want to see the pros and cons of any feasibility study and clarity of intention. We would be very keen to see details before saying Manukau is the right place, but certainly for ships coming from Australia a west coast port could be beneficial."
Harbord said it was important before the study began that there was clarity on whether a port at Manukau Harbour was intended as an international "hub" port or a "spoke" port for regional shipping calls.
"There have been numerous studies. We would be looking for how it fits into the Ministry of Transport's (total freight) strategy, does it replace Ports of Auckland, how it fits into the supply chain.
"It's really important that clarity on this is provided before the study kicks off. Otherwise what are they evaluating?"
Don Braid, managing director of listed, Auckland-headquartered global logistics company Mainfreight, was unimpressed.
"Yet another study for the consultants to feed off. Why don't they dust off the old one that clearly outlines the difficulty of establishing a port on the Manukau? Why do we need another port in Auckland - just get the current one operating efficiently."
However, he welcomed the Budget news of $349 million for new trains and wagons for SOE KiwiRail, saying they were much needed.
Port of Tauranga chief executive Leonard Sampson said the dry dock proposition for Northport had been contemplated for five or so years and research was "a long way down the path".
The Manukau Harbour option for an alternative Auckland port had been looked at before by the previous parliamentary term's coalition Government, he said.
The shipping access challenges of the Manukau option had been documented.