Questions over Auckland's power supply 

Source: ONE News

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Friday's outage has left many people questioning why Auckland's power supply is so exposed and how one forklift could leave three quarters of a million people without power.

"The Otahuhu substation has two circuits on one set of towers which serve the customers with either of the circuits in. Normally both circuits are in operation," says Transpower spokesman Patrick Strange.

But on Friday morning one of those circuits was under maintenance and when a problem occurred and the remaining line went down, thousands of people from Auckland north were left with no power.

This is not the first time a failure in the system has led to blackouts. In 2006 an independent report blamed the blackout on bad maintenance at Otahuhu.

And in February this year, Auckland businesses faced cuts two days in a row.

North Shore City's mayor says the current system is not good enough.

"You've got a huge area from the Auckland Harbour Bridge right up to Kaitaia dependant on one set of towers," says Andrew Williams.

Transpower is working on a half-billion dollar upgrade which will mean that even if one of the circuits is lost, the power will continue to flow.

But that will not be finished until 2013 and for the thousands affected on Friday, the upgrade cannot come soon enough