Mokopeka Hydro Station

Engineering Work (eg road, bridge, sawmill, dam)


This is the oldest operating power station in New Zealand (and probably in the world), running continuously since 1892! The plant is still in good condition and is capable of supplying space-heating and emergency lighting to the Mokopeka homestead nearby

Hawkes Bay pioneer farmer/engineer John Chambers first became interested in the new science of electricity in the mid 1870s, within five years of Thomas Edison’s invention of the incandescent lamp. During the 1880s Chambers studied practical electrical engineering by correspondence with an American university, and on the completion of his course set about the task of building his own generating plant and electrical appliances. He designed his power plant based on a 14 hp Victor turbine by Frederick Well, London, and a second-hand 8kW – 110V d.c. dynamo originally installed in the Midland Railway Co Ltd’s St Pancras Station, London in 1886.

While he awaited the delivery of the plant, Chambers built a dam across the Maraetotara Stream, constructed a 600 ft headrace canal, excavated a tailrace tunnel and turbine enclosure, and erected a power house to contain the electricity generating plant and associated control equipment.

Designing and installing the plant was only part of the project. Chambers also erected poles, insulators and overhead lines to the homestead, workshop and shearing shed, and installed the internal wiring within these buildings.

In September 1892 the plant was completed and the turbine operated for the first time.

By the turn of the century, Chambers used electric motors to power all his farm appliances – his workshop grinder, drill press and lathe as well as his shearing shed and woolshed. He subsequently invented and developed small independent shearing hand-pieces that were driven by electric motors and flexible leads.

Early 20th century demand for electricity overtaxed the original dynamo. In 1926 Chambers imported and installed a larger turbine and dynamo and converted the original dynamo into a motor to drive the water pump. The new turbine gave Mokopeka the luxury of an automatic governor which regulated the water supply to provide a near constant voltage output, thus alleviating some of the previous control difficulties. No other New Zealand generating plant was so advanced at that stage.

Electricity remained unavailable to most Hawkes Bay people until the 1920s, and some of Chambers’ neighbours did not received electricity until the 1940s, 50 years after he had gained its benefits.

In 1965, after severe drought periods, the Maraetotara Stream could no longer provide sufficient water to meet, by then, the considerable demands for power at Mokopeka. It was at this point that the Chambers family decided to take supply from the Power Board, after more than 75 years of supplying their own electricity. However, the hydro plant was retained to provide heating to the homestead and still does this today.

Heritage recognition
IPENZ “Engineering to 1990” project
This item of New Zealand’s engineering heritage was recognised as part of the IPENZ “Engineering to 1990” project which the Institution organised to help celebrate the country’s sesquicentenary in 1990. A plaque was unveiled to mark the significance of this power station as part of the development of the nation.


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Mokopeka, Hawkes Bay

Hawkes Bay

Access Info
You can view the dam and one of the buildings (but not inside as it is locked up) via a walk along the Maraetotara Stream walkway which is about 2-3km up the Maraetotara Road.

Nature of Engineering
Electrical Power Generation and Distribution, Infrastructure (incl. Road, water, ports)


IPENZ's 1990 celebration plaque

(Click image to enlarge )

Lat: -39.757236 Long: 176.924692