WHAKAMARU HYDRO STATION

The Whakamaru Hydro Station is about 40km north of Taupō.

Opened: 1956
Number of generating units: 4 Francis turbines
Total output: 124MW
Average Annual Output: 515GWh
Refurbished and recommissioned 2017-20, adding ~5MW per unit

State Highway 30 runs across the top of the Dam.



Construction of the Whakamaru Hydro Station and Hydro Dam began in 1949, and the station became operational in 1956.

It was one of nine hydro stations and eight hydro dams constructed on the Waikato River from the 1920s through to 1970, which now comprise the Waikato Hydro System operated by Mercury. 

The Whakamaru Hydro Dam was built using 270,000 cubic metres of concrete and 1000 tonnes of reinforcing steel.

The dam has short penstocks connected to four Francis turbines inside the hydro station. The original turbines had an installed capacity of 26MW per unit and were delivered by the former Dominion Engineering (Canada), now part of ANDRITZ Hydro.

In 2017, after 61 years of service, the turbines, generators and governors at Whakamaru were replaced with modern equivalents. 

ANDRITZ, GE and MBCentury were contracted to complete the four-year refurbishment project, which added another 5MW per unit, moving total installed capacity to 124MW.

The new Francis turbines are able to generate more energy from the same volume of water, moving the station’s average annual output to 515GWh, enough to power the equivalent of about 64,000 residential homes.

Whakamaru is the main switching station for upper Waikato generation and supplies the transmission system that leads north. This includes output from Mōkai Geothermal Station fed through the Whakamaru G4 switchyard.