Powering Northland:
Ngāwhā Geothermal Plant Expansion

New Zealand’s geothermal activity is traditionally most associated with Taupō. but modern development in the upper North Island has changed that perspective.

The Far North electricity generation and lines network company Top Energy, contracted United Civil to complete civil works on the $182m Ngāwhā Geothermal Plant expansion for Ngāwhā Generation Limited. These works will more than double Top Energy’s geothermal generation capacity and eventually produce enough electricity to power 90 per cent of the Far North.

Key features included:

• completing around  1,000,000m³ of mostly cut-to-fill earth works in some of Northland’s most sensitive soils – including installation of around 90,000 metres of wick drainage and 100,000 tonne of temporary preloads
• extensive erosion and sediment control works
• construction of 12,000 metres of drainage and stormwater pipework at depths of up to six metres
• constructing 150,000m² of pavement and 6km of site roads
• forming multiple large scale platforms to accommodate the new power plant, together with production and reinjection wells
• working alongside and supporting the activities of numerous other specialist contractors (e.g. well drilling contractors).