Prime minister John Key has officially opened the largest infrastructure project in New Zealand, the North Island Grid overhead line upgrade. The prime minister visited Pakuranga substation at the northernmost point of the project, where he met with engineers and managers from the companies involved in its construction.

BBUGL, a joint venture between Balfour Beatty Utility Solutions and UGL Limited which carries out work in Australasia, undertook the construction of a new overhead transmission line as part of the project, in alliance with Transpower, the state-owned company which owns and operates New Zealand’s national grid. BBUGL began work on the line in 2010, and since then has constructed 186km of new 400kV overhead line, including the erection of 432 new transmission towers and installation of over 7000 tonnes of conductor. The line includes several ‘monopole’ towers designed in partnership with the local council to fit with the topography of the area, reducing impact on rural settings. Standing at 65m, these are the tallest transmission poles anywhere in New Zealand.

The project, which in addition to the new line also includes two new substations and underground cabling, will reinforce the electricity supply in New Zealand’s North Island. The population has more than doubled in this area since the last major work was carried out on the grid in the 1960s, putting increasing strain on infrastructure.<br /><br />The project is one of several important infrastructure schemes being undertaken by BBUGL in New Zealand and Australia. Global investment into electricity transmission expected to be worth £380 billion between 2010 and 2020.