Arapuni Power Station

Story

Arapuni Power Station is a hydroelectric power station on the Waikato River, in the North Island of New Zealand. It is owned and operated by Mercury Energy, and is the seventh and penultimate hydroelectric power station on the Waikato River. It is also the oldest currently generating, the first government-built, and the largest single hydroelectric power station on the Waikato River.Arapuni, due to its proximity to Hamilton, plays an important part in voltage support and frequency keeping in the city and the wider Waikato region. Even though it is 80 years old, continuous improvement and refurbishment of the station's generation equipment ensures Arapuni remains efficient.The powerhouse and dam at Arapuni are under protection of the Historic Places Trust, becoming Category I Historic Places in November 1987 and August 1991 respectively. It is one of the few generating power stations in New Zealand to be listed on the register.HistoryArapuni was the first government-built hydroelectric station on the Waikato River, and the second after the privately owned Horahora Power Station that was decommissioned in 1947 on the filling of Lake Karapiro.Initial surveying of the site began in 1916, but in 1920, the surveying was halted due to lack of government funds to progress the project. Construction of Arapuni finally began in 1924, but repeated heavy rain and the resulting floods dogged the early works. The station, complete with three turbines and provisions for a fourth, was commissioned in mid-1929. Shortly after commissioning, Arapuni was closed for two years while a water seepage problem was investigated and the headrace lined. The station, with the addition of a fourth turbine, was recommissioned in May 1932.