Rare chance to see station

Rare chance to see station

A rare chance to have a tour of the Mangahao Power Station to mark 100 years since it first began operating was snapped up at the weekend.

Organisers put on 11 bus trips that transported 465 ticket holders from Shannon to the station near the foot of the Tararua Ranges. Many either worked there or were connected through family that had, so it meant a great deal to have the chance to see inside.

The Mangahao Power Station near Shannon has a special place in New Zealand’s hydroelectric development. Commissioned in November 1924, it was the first major hydroelectric power station built by the government.

Construction started in 1919 and involved diverting water from the Mangahao River through a series of tunnels and pipelines totalling 4.8 kilometres within the Tararua Ranges. It was an ambitious engineering feat designed to harness the river’s flow for electricity generation.

The station was officially opened by Prime Minister William Massey on November 3, 1924. It was a hugely important infrastructure development at the time for New Zealand.

The station featured three storage dams and had a substantial hydraulic head of 271 metres to drive its turbines.

In 2004, the original smaller generating sets were replaced by a 26 MW Francis turbine unit, increasing the station’s capacity to 38 MW. The station’s mean annual output is about 135 GWh, contributing significantly to the region’s electricity supply.

The facility is currently owned and operated by Manawa Energy, in partnership with King Country Energy, who combined to organise the tour and open day at the weekend.

Manawa Energy general manager Todd Mead and King Country energy chief executive Chris Fincham said that to acknowledge the centenary in November last year and the station’s history, it was decided to open the doors for a public viewing day.

A feature of the tour was the museum on an upper floor of the station that holds historical photos and artefacts.

The Mangahao scheme laid the groundwork for future hydroelectric projects in New Zealand and played a crucial role in establishing the North Island transmission grid, connecting to major centres like Wellington, Palmerston North, Whanganui, Masterton, Napier and Hastings.

The Mangahao Power Station is listed as a Category 2 historic place by Heritage New Zealand, acknowledging the station’s importance in the nation’s industrial heritage and its role in the development of New Zealand’s electricity infrastructure.