The New Zealand Shippers' Council says the country could save millions by using bigger ships.
Port of Tauranga has received backing from the Environment Court to deepen its shipping channel, enabling larger container ships to use the harbour.
Port of Tauranga wants to deepen the channel by up to 17.4 metres.
The dredging would allow the port to accept vessels up to 40% larger than can now be handled at the country's biggest port, Ports of Auckland.
The Shippers' Council says the value of having bigger ships operate on the South East Asia route could be up to $338 million a year from 2015, increasing up to $391 million a year by 2020.
The council says these figures exclude the significant flow-on benefits to the rest of the economy.
Tauranga's Chamber of Commerce president Warwick de Vere says Tauranga will reap the economic benefits of the development.
He says with the use of larger ships it's possible to bring more cargo in for the same freight costs, so the unit cost of any cargo in or out reduces on a unit basis.
Environment Court backs plan
Port of Tauranga has received backing from the Environment Court to dredge its shipping channel, which would enable larger container vessels to use the harbour.
The court is recommending the Minister of Conservation grant consent for the scheme that would deepen the channel by up to 17.4 metres.
About 15 million cubic metres of material would be removed.
The port company's chief executive, Mark Cairns, says deepening the shipping channel is a way to future-proof the port and would give the company a competitive advantage.
"It'll allow us to be competitive with the large Australian ports. If we don't provide that in New Zealand our exporters will have to trans ship and we'll just be a hub through Australian ports."
The Environment Court has advised the company to liaise with other parties including local iwi which have expressed concern about the project.
Mr Cairns says dredging can get away as soon as the Conservation Minister has signed off the recommendation.
The port was given 30 working days to circulate proposed draft conditions.