A new study on ports in the upper North Island has Port of Tauranga chief executive Mark Cairns asking how many studies does an industry need.

Auckland Council is commissioning a consultant to look at ports in the upper North Island on behalf of a council grouping known as the Upper North Island Strategic Alliance (Unisa).

This follows a final report by the Productivity Commission released in April and earlier reports by the Ministry of Transport and the New Zealand Shippers' Council.

A protracted industrial dispute at Ports of Auckland has raised awareness of the issues facing the port industry, which has been debating for a long time if there should be a port handling huge container ships in downtown Auckland in the future.

The question Mr Cairns poses is, "How many of these studies do we need?"

"Do we need to keep doing reports until it gives the answer Unisa, or Auckland Council want," he said.

Those wishing to carry out the port study for Auckland Council have to apply by Tuesday. The study is the first stage of a wider programme of work on port development by Auckland Council in partnership with the alliance of upper North Island councils.

The consultants are being asked to look at a greater role for inland ports or freight hubs, rail capacity and shipping trends.

The idea of a merger between Ports of Auckland and Port of Tauranga has been mooted previously but it did not proceed.

CentrePort in Wellington last week welcomed progress on the Transmission Gully highway, which will improve road connections to it.

An independent board of inquiry draft decision released on Friday says it will approve resource consents for the controversial $1 billion, 27km highway from just north of Wellington to the Kapiti Coast.