The Connemara (file image). Photo: RNZ/Anthony Phelps
Bluebridge owner StraitNZ has confirmed its ferry the Connemara lost power in the Cook Strait last month because of contaminated fuel.
RNZ this week revealed fuel problems were the likely cause of the Connemara's power loss, leaving it drifting for more than two hours and needing a rescue from tug boats.
Until Friday, StraitNZ had not commented on the cause, citing the ongoing Maritime NZ investigation.
But the Ministry of Business, Innovation and Employment, Maritime NZ, and Transport Minister Simeon Brown all confirmed StraitNZ had advised fuel issues might have been a contributing factor.
Until now, it has been unclear what exactly the fuel problem was - but in a statement, StraitNZ chief executive Shane McMahon confirmed the fuel was "contaminated".
The contaminated fuel damaged the ship's fuel injectors which caused the loss of power, he said.
The injectors had been repaired and the contamination had been cleared with the use of a biocide additive.
Investigations into how and where the fuel was contaminated are ongoing, and StraitNZ was working with authorities and its fuel supplier to determine the source of the contamination, McMahon said.
"Samples of fuel taken from the ship and its fuel supply since the 19 September incident have shown no contamination," McMahon said.
Industry should have been told earlier - union
The union representing ship masters and officers said Strait NZ and Maritime NZ should have fronted up on the Connemara's problem immediately.
It has been one month since its power loss.
Since then, StraitNZ had replaced the Connemara's fuel and cleaned its storage systems, Maritime NZ said.
"No issues have been identified with recent sampling of fuel supplied out of Wellington," it said.
"If there were, appropriate people would have been notified."
But its ongoing investigation could take a year.
"The purpose of our investigation is to understand the cause of an incident, to see whether there are underlying systemic issues, identify the potential for safety lessons for the sector, and work out whether it is in the public interest to take an intervention," Maritime NZ said.
The industry should have been told the fuel was contaminated, said Merchant Service Guild vice president Captain Iain MacLeod.
"Maritime NZ needs to be upfront about what it knows and what steps it is taking to advise maritime operators how to prevent any further issues."
Before the fuel contamination was confirmed, Transport Minister Simeon Brown told RNZ he was satisfied with Maritime NZ's communication to him and the public about the Connemara's power loss.
"It is appropriate that Maritime New Zealand be given the space it needs to independently investigate the causes of safety incidents so that they can be avoided in future," he said.
"Investigations can take different lengths on time depending on the complexity of the incident and I expect the regulator to appropriately respond to the risks involved to ensure the safety of New Zealanders."
KiwiRail, which runs Interislander's Cook Strait ferries, had not reported similar fuel problems, Brown said.
RNZ has approached Brown for further comment, now that this new information has come to light.
Resources Minister Shane Jones told RNZ earlier this week that while speaking with representatives from major oil company Mobil on a separate matter, they assured him there was no problem with its fuel - but it could be that ship engines were not coping with an added emulsifier.
Mobil does not supply fuel to Bluebridge and said it would not speculate on the Connemara's problem.
Jones said he would await the outcome of MBIE's investigation into the fuel problem, which includes its own testing of fuel samples.
He was not concerned about the quality of fuel in New Zealand, or that there may be a widespread issue.
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