Auckland power cable 'possibly' intentionally damaged, causes diesel leak

Police are speaking with two people after a diesel leak in the South Auckland suburb of Manurewa.

Fire and Emergency earlier discovered that it was a power cable - not a fuel pipe - that caused the leak Monday.

Three crews were called to the scene on Great South Road in the suburb of Manurewa at 6.30am.

It had been contained and crews had left by 11am.

Police said they were "speaking with" two people in relation to the leak.

Detective senior sergeant Michele Gillespie, of the Counties Manukau Crime Squad, said police were made aware of a potential gas leak early on Monday.

Upon arrival, Gillespie said it was determined to be a Northpower pipe, carrying cooling oil, which had been damaged.

"Police do not believe the pipe is connected to the nearby service stations," Gillespie added.

Northpower helped Fire and Emergency to establish that it was a power cable with fuel insulation around it in order to cool it down.

FENZ assistant commander Chris Delfos told RNZ it worked with Northpower to stem that leak.

He said it was unable to drain the pipe as that would damage the cable further, and cost the supplier millions of dollars.

Delfos said it was possible that the initial damage was intentional.

He said the cable began leaking at 3am, which had caused diesel to spill into the Papakura Stream.

He hoped enough had pooled on the nearby grass area, but said there would be "some ecological damage to the waterway".

Fire and Emergency would work with Auckland Council to mitigate as much of that as possible, Delfos added.

He said there had also been a telephone line cut nearby, but would not comment further on that.

Firefighters at the scene captured the fuel which was leaking out of the pipe under a nearby bridge, and decanted it into a yellow bucket. The bucket was about a quarter-filled, which Delfos understood was around 75 litres.

There was initial confusion due to the U-GO Manurewa petrol station being cordoned off, but Deflos said that was due to it being still under construction.

Earlier, Delfos told the New Zealand Herald that it appeared there had been some sort of "sabotage" to the pipe.

In a later press conference, Delfos said the damage was "possibly" intentional.

A Northpower spokesperson said the cable affected is in the Vector network area.

"Northpower Energy Services contract to Vector for some work in the area," a statement said.

Anyone with additional information is asked to update police - online, or by calling 105 - using the reference number P065915628.

Information can also be provided anonymously via Crime Stoppers on 0800 555 111.

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