They deliver electricity to our properties but, to some criminals, power lines have become a source of profit.
They're stealing the copper to sell as scrap metal, but there are fears someone could be seriously injured or even killed.
With live wires exposed, cut power lines are a dangerous electric-shock hazard.
"People die doing that sort of stuff," said Jeff Harris from Macaulay Motors.
But danger hasn't put these people off.
Thieves have been caught tampering with power lines to steal copper and sell it as scrap metal.
"In my 30 years at Orion I have never seen this sort of brazen theft before," said Steve Macdonald, network general manager at Orion Electricity.
It began 18 months ago in the red zone of Ōtautahi/Christchurch.
It's a barren landscape away from watching eyes, putting would-be thieves in pole position.
But, in the past six months, thefts have increased and expanded from Springfield to New Brighton.
"We've got businesses and houses that are occupied, and they're turning up to work or home the next day and finding they're without power," Macdonald told Newshub.
Copper is valuable - its average price is $10 a kilogram.
"There's easier ways to go and earn an income, go and get a job," Harris said. "For the sake of a few dollars trying to get some money and it's a massive risk."
And it's a risk not only to the perpetrator.
"Members of the public, dogs, kids. They could suffer a serious electric shock - or worse - and that's what I'm worried about," said Macdonald.
It's not just power lines - people are also tampering with power boxes and not only in Ōtautahi Christchurch.
"I'm quite aware that it's happening throughout New Zealand to varying degrees," Macdonald said.
Repairs have cost Orion up to $1 million so far.
"I just can't believe people are doing this and putting others and themselves at risk."
