After the major power outage that occurred in Auckland, New Zealand, in June 2006, Transpower, the owner and operator of the national grid, is striving to achieve improved reliability within five years. It is being aided by two independent reports examining the blackout, which left about 750,000 customers without power, resulting in US$52 million lost in trade.

According to a report by Sinclair Knight Merz, high winds triggered the failure of connection equipment at the Otahuhu Substation, the sole link leading to Auckland. Prior to the outage, Transpower had proposed a 400-kV project from Whakamaru to Auckland to improve the reliability of supply to Auckland and the Northland regions, but the New Zealand Electricity Commission rejected the proposal. Now Transpower is in the process of revising the proposal to operate initially at 220 kV and to migrate to 400 kV over time.