Traffic was earlier thrown into chaos when nearly three dozen sets of traffic lights went out across the city contributing to a four-vehicle crash at the intersection of Marshland and Prestons Rds
Crash at the intersection of Marshlands Rd & Prestons Rd causing delays. The traffic signals are out due to a power outage. Take care.^SM pic.twitter.com/g6FtHw5XXt
A Transpower spokeswoman Rebecca Wilson said a fault in the Twizel area suddenly cut electricity to a wide area across the island this morning.
Wilson said the widespread blackout was the result of a "frequency event".
"A frequency event is when power drops below its normal frequency it starts to disconnect customers to protect the system," she said.
Orion spokeswoman Linda McGregor said more than 50,000 customers were affected because of a problem with a Transpower transmission line supplying the city from Twizel.