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Vector Energy is likely to seek compensation from a third-party contractor believed to have caused the second major power cut in the Auckland region in 24 hours.
This morning supplies were lost to parts of Papakura, south Auckland, for two hours from 9.58am after a contractor damaged cables. More than 430 homes and businesses were affected.
Last night tens of thousands of homes were plunged into darkness after an explosion at a substation caused a power cut that crippled Auckland's North Shore.
Vector Energy spokeswoman Philippa White said the outage in Papakura was fixed before 1pm.
Most customers had their power restored within 20 minutes, but 58 in the Wood St area had to wait until 12.40pm, she said.
Ms White said the outage occurred when a thrust boring machine from a third party contractor was drilling underground and damaged a cable.
She said it was likely Vector would seek some compensation from the contractor.
"We do generally put together a third party compensation claim when they cause outages," Ms White said.
"Third parties need to be responsible and make sure they are clear of underground cables. We have free maps available of our network so there's no reason why they shouldn't know where they are."
Ms White said it was too early to know how much repairing the outage had cost. She was unsure whether the retailers in the Papakura central business district who lost power could claim compensation.
Traffic lights were out in the main street and banks and shops were closed during this morning's cut in Papakura.
Jhinna Ali from Papakura Appliance and Things said his morning was ruined and he lost about $300.
He said the phone went out he couldn't work on fixing any appliances because the rainy day darkened his shop.
An internal fault at Mt Albert Grammar school also saw students knock off early because of a lack of power.
Principal Dale Burden said: "There's no power. There's no heating and it's also a wet day and a dark day." There was no link to the other power outage problems over the past 24 hours.
Lights on the Northern Motorway and harbour bridge were cut yesterday, as was power to homes and shops in many suburbs, including parts of Greenhithe and Albany.
Cameras monitoring the motorways and traffic lights were also affected, as were North Shore businesses, including cinemas, which lost power halfway through screenings.
Engineers were last night still investigating what caused the Wairau Rd substation blast, which happened at 7.43pm.
Power to about 30,000 homes was mostly restored by 8.20pm.
Ms White said it was possible investigators might not discover what caused the substation explosion on the North Shore last night.
"It could be a couple of days before we know much more about that," she said.
"But there's a chance that the evidence we need to discover the cause might have been blown up in the explosion."
North Shore Hospital had to switch to its emergency power generators, but had communication difficulties after losing some of its cellphone coverage.
Vodafone spokesman Paul Brislen said five cellphone transmission sites in the company's network were disabled by the power cut, but most had enough back-up battery power to keep operating.
The Bridgeway cinema on Northcote Pt gave refunds to dozens of patrons watching movies showing on its two screens when the projectors stopped running.
"Some of our patrons sat there for a while, hoping the power would come back on," said duty manager Jean Smith.
Others went next door to the Sausalito cafe and bar, where duty manager Jenny Peters had an emergency box of candles stowed away for such occasions.
"It's happened a few times," she said of the power cut.
"We couldn't cook, but people were just hanging out, having a drink."
Piotr Jasica and David Cookson were enjoying a quiet beer at the Northcote Tavern when the lights went out.
"It was actually quite nice but it was pretty quiet for a while," said Mr Jasica.
"The important thing was they were still able to serve the beer cold and when the candles came out it was all quite romantic ... just don't tell our wives."
Publican Kim Milne said the tavern had emergency lighting and gas fires to keep patrons warm despite none of the customers seeming to mind too much.
A Fire Communications Centre spokeswoman said the first call about the power cut came from an off-duty policeman who saw the substation explosion.
Firefighters were sent to the substation in Wairau Rd, where a small fire was found in a circuit board.
Police and fire services received other calls from concerned residents who had been left in the dark but there was little emergency service workers could do to help.
One witness said: "I was driving home across the bridge and the lights went out. The lights on the North Shore just vanished in front of me. It was surreal."
A Birkdale resident said: "One odd thing was that we suddenly saw the stars because the street lights were all off."
- Additional reporting: Maggie McNaughton, Mathew Dearnaley, NZPA
