Last updated 21:48, March 11 2016
The area around Hole in the Wall, off Coromandel, lies in the busy shipping route between the ports of Auckland and Tauranga.
The incident, through an area called Hole in the Wall off Coromandel, which lies in the busy shipping route between the ports of Auckland and Tauranga, came to light thanks to a coastal navigation safety review carried out by Maritime NZ.
It highlighted specific risk areas in Hauraki Gulf, Colville Channel off Coromandel, and Cook Strait, which it described as "one of the more unpredictable waters in the world".
It was prompted by an expected increase in the number of ships visiting New Zealand, a trend toward larger ships, and technology changes in navigational aids, Maritime NZ said.
It found coastal shipping was largely well-managed and there was a "sound framework in place to manage the movement of ships around the New Zealand coast, with procedures in place to assess risk and adjust safety measures if required".
The Hole in the Wall, off Coromandel between "Sunk Rock" and "Old Man Rock", is identified by Maritime NZ and Environment Waikato as being unsafe for vessels weighing more than 500 gross tonnes.
But a "large" cruise ship in 2014 tracked through the gap.
While the ship's name or weight is not in the report, large cruise ships visiting New Zealand have been more than 120,000 tonnes – more than 24 times the recommended safe limit.
"There may be a temptation for cruise ships to take this route to enhance the tourist experience," the report said.
The decision to use the unsafe gap prompted a letter from Maritime NZ to the shipping company, which responded that it would not take the passage again "except in strict compliance with local requirements".
Maritime NZ spokesman Steve Rendle said the ship came within 500 metres of rocks on one side and 600m on the other. While it was an "unusual" route fo the ship to take, it was not a breach of rules.
"It is fair to say the vessel was not in danger at any time," Rendle said.
Coromandel MP Scott Simpson welcomed the focus on the area, especially in light of the Rena grounding.
"There's an obvious concern following the Rena, which highlights concerns about coastal navigation in large vessels," Simpson said.
The report also highlighted an issue on a Panama-flagged bulk carrier that came from Fiji to Wellington, where it was found in 2013 to have a compasss eight degrees out. Maritime rules allow a deviation of up to five degrees.
It highlighted three areas of New Zealand which needed monitoring to see if more needed to be done to lessen risks.
Cook Strait, which had gale force winds 107 days per year and heavy swells, had New Zealand's highest volume of traffic when passenger ferries were included.
Yet, the Colville area – which the Hole in the Wall was in – is identified in a graph of risk as about twice as dangerous as Cook Strait, which came second.
Port representatives around New Zealand were "unanimous in their concern about logging ships", the report said.
"At one port it was observed that recently a log ship headed out into a storm when most of the crew must have been exhausted from lashing logs."
A change to maritime rules, which comes into effect in March next year, means Maritime NZ will have more power in stopping tired crew from leaving port.
Shipping Federation executive director Annabel Young said a growing economy as well as increasing numbers of cruise ships were the reasons shipping was forecast to increase.
"The report paints a picture of exhausted workers on international voyages making mistakes as they move around the New Zealand coast, going from port to port."
The report made it clear that some foreign ships may not have "working radios, an accurate compass, up-to date charts or up to date navigational information", she said.