A major study of Auckland's port needs says future sea freight business should be moved to a new "super port" in the Manukau Harbour or the Firth of Thames.

The Port Future Study concludes that in the long term Ports of Auckland will not be able to continue operating at its current downtown location and a new site needs to be found, at a cost of $4 billion to $5.5 billion.

The investigation argues that Tauranga and Northport ports will be unable to cope with the growth in Auckland freight together with their own demands.

The Port Future Study - made up of representatives from business, Ports of Auckland, community groups and iwi - has narrowed down the possible new port locations to Manukau Harbour and the Firth of Thames, subject to more detailed investigation.


In the short to medium term - between now and 2065 - the report recommends no further reclamation at the Fergusson container terminal but a need for extra berth length at Bledisloe Wharf for vehicle imports and other bulk cargo.

The report does not make any specific recommendations, but discussions have taken place among the port study's consensus working group and wider reference group for an extension of about 25m between two concrete piers at the end of Bledisloe Wharf to create a new east-west berthage space.

Ports of Auckland are understood to be seeking a 65m extension.

In recent years the port company had pushed for extensions to Bledisloe Wharf of up to 179m.

The report, commissioned by Auckland Council following last year's battle over wharf extensions of about 96m into the Waitemata Harbour, has made a number of recommendations that will be considered by the council's Auckland development committee next week.

The Herald has campaigned against further reclamation of the harbour for port use.

The report's recommendations include establishing a port relocation site, further investigations into the preferred Manukau and Firth of Thames sites and regular monitoring of trigger points to find the best time to move the port.

"Auckland must decide soon how to provide for the future growth of port capacity and about the implications of that long-term strategy for short-term port development plans," the report said.

The report found that retaining the bulk of port functions is better than shedding cargo elsewhere or downsizing in the short to medium term.

Shedding or downsizing freight operations may weaken the case for moving the port, it said.

The report said the port should move when the social, environmental, cultural, economic, urban development and other conditions are right for the city centre or Auckland or New Zealand.

It was also possible that Auckland's future unfolds in a way that does not trigger the need to move and it can accommodate the long-term demand at the current site.

In the 2014-2015 year, Ports of Auckland handled 970,000 containers, three million tonnes of freight and 250,000 cars.

The number of containers is expected to grow to three million over 50 years and "considerably beyond three million" over a much longer time period, the report said.

A new port in the Manukau Harbour or the Firth of Thames could handle 10 million containers.