Many of the reservoirs and dams in
New Zealand''' have been developed principally to produce
hydroelectricity.
Hydro-electric dams
The main river systems comprising a series of dams and powerhouses are situated on the following rivers:o
- The Waikato River
- The Waitaki River
- The Clutha River
Other schemes are standalone developments associated with specific sites.
Tongariro Power Scheme
The Tongariro Power Scheme (1,400 GWh) diverts water from the south side of
Mount Ruapehu and Tongariro into Lake Taupo.
The Waikato
The hydro stations, starting from
Lake Taupo, are (capacity in MW and nominal annual energy output in GWh):
- Aratiatia (84 MW) (331 GWh)
- Ohakuri (112 MW) (400 GWh)
- Atiamuri (84 MW) (305 GWh)
- Whakamaru (100 MW) (486 GWh)
- Maraetai (360 MW) (855 GWh)
- Waipapa (51 MW) (330 GWh)
- Arapuni (171 MW) (805 GWh)
- Karapiro (90 MW) (490 GWh)
The Waitaki
The river was developed in multiple stages. The
Waitaki dam was built first, without earthmoving machinery, followed by the development of the
Aviemore Dam on
Lake Aviemore and
Benmore Dam on
Lake Benmore.
Lake Pukaki was initially dammed at this stage to provide storage and flow control. A small station was also installed on
Lake Tekapo, but although it has a small dam to raise the pre-existing lake, water was taken through a 1.6 km tunnel to a powerstation below the level of the lake.
In the 1960s, work was started on the Upper Waitaki project. This project consisted of taking the discharge from the original Tekapo (A) station through a canal to the edge of Lake Pukaki, with Tekapo B station between the canal and the Lake. The dam at Pukaki was increased in height. Water from Pukaki is then transferred into a canal which meets a canal from Lake Ohau, where it drops through Ohau A into Lake Ruataniwha. Lake Ruataniwha feeds a further canal, with Ohau B midway along, before emptying through Ohau C into Lake Benmore.
The stations are (capacity) (annual output) (commissioned)
- Tekapo A (25 MW) (160 GWh) 1955
- Tekapo B (160 MW) (800 GWH) 1977
- Ohau A (264 MW) (1150 GWh) 1980
- Ohau B (212 MW) (970 GWh) 1984/1985
- Ohau C (212 MW) (970 GWh) 1984/1985
The original Waitaki power stations discharge water back into the Waitaki River which then forms a storage lake for the next station in the chain.
The three power stations are:
- Benmore (540 MW) (2,200 GWh) 1965
- Aviemore (220 MW) (940 GWh) 1968
- Waitaki (105 MW) (500 GWh) 1935
Project Aqua was a proposed scheme of 6 dams on a man made canal running from the Waitaki Dam to the sea. It was cancelled by Meridian Energy Limited on 29 March 2004.
see also Lake Benmore, Lake Aviemore, Lake Ruataniwha, and Lake Waitaki
Clutha River
Standalone Hydro schemes
- Manapouri does not rely on a high dam to provide water - it takes advantage of the natural 178-metre height difference between Lake Manapouri and the sea at Deep Cove in Doubtful Sound, in Fiordland. The power house is in an underground cavern, while two tailrace tunnels take the water from the power house 10 km to Deep Cove and the sea. The Manapouri Control Structure (Mararoa dam) downstream from the original outlet of Lake Manapouri controls the lake level, and feeds water from the Mararoa river back up the river into the Lake.
Other Schemes in the
North Island
- Kaimai Scheme - Kaimai (0.4 MW), Lloyd Mandeno (15.6 MW), Lower Mangapapa (6.25 MW), Ruahihi (20 MW) - Scheme: (165 GWh)
- Aniwhenua Dam (25 MW) (135 GWh) - Bay of Plenty (Upriver from Matahina dam)
- Matahina Dam (36 MW) (300 GWh) - Bay of Plenty
- Lake Waikaremoana Scheme - 3 Dams: Kaitawa (36 MW), Tuai (60 MW), and Piripaua (42 MW).
- Wheao & Flaxy (26 MW) (115 GWh)
- Hinemaiaia - A (2.25 MW), B (1.35 MW), C (2.85 MW) - (30 GWh) - near Taupo
- Motukawa (4.6 MW) (25.8 GWh) - Taranaki
- Mangorie (4.5 MW) (20.9 GWh) - Taranaki
- Patea Dam (31 MW) (115 GWh) (Peak Station) - Taranaki
- Mangahao Dam (30 MW) - Tararuas
- Kourarau Scheme (1 MW) - Wairarapa
Other Schemes in the
South Island
- Waihopai (2.5 MW) (11.8 GWh)
- Branch River - (Wairau & Argyle Stations) (11 MW) (54.3 GWh) - Run of River canals.
- Cobb Dam (32 MW) - Golden Bay
- Arnold Dam (3 MW) (25 GWh) - West Coast
- Dillmans (0.5 MW), Duffers (3.5 MW), Kumara (6.5 MW) - Scheme: (47.9 GWh)
- Kaniere Forks (0.43 MW) (3.75 GWh) & MacKays Creek (1.1 MW) (8 GWh)
- Wahapo (3.1 MW) (14.5 GWh) - South Westland
- Lake Coleridge (45 MW) (205 to 300 GWh) - Canterbury - Diverted rivers and natural lake.
- Highbank (25.2 MW) (115 GWh) - Canterbury - joint power & irrigation.
- Montalto (1.1 MW - 1.8 MW) (12 GWh) - Canterbury - joint power & irrigation.
- Opuha Dam (7.5 MW) - Canterbury - joint power & irrigation.
- Paerau (10 MW, 47.8 GWh) & Patearoa (2.25 MW, 7.5 GWh) - Taieri River, Otago - joint power & irrigation.
- Waipori - 4 Dams (12 MW, 57 MW, 7 MW, 8 MW) - Dunedin
- Monowai (6 MW) (34 GWh)
- Roaring Meg - 2 power stations (1.3MW, 3MW) (30 GWh)
Water supply dams
- Upper Huia Dam - Auckland
- Lower Huia Dam - Auckland
- Upper Nihotupu Dam - Auckland
- Lower Nihotupu Dam - Auckland
- Waitakere Dam - Auckland
- Cosseys Dam - Auckland
- Mangatangi Dam - Auckland
- Mangatawhiri Dam - Auckland
- Wairoa Dam - Auckland
- Hays Creek Dam - Auckland
- Macaskill Lakes - Upper Hutt
- Opuha Dam - Canterbury, also has small hydro-electric scheme (7.5 MW)
- Whau Valley Dam - Whangarei
- Wilsons Dam - Whangarei
Defunct dams
- Birchville Dam - Upper Hutt
- Karori Reservoir - Wellington (now a nature reserve)
Irrigation dams
- Lakes Manuwai and Waingaro at Kerikeri, purpose-built irrigation dams containing 12,800,000 m3 of water
See also
External links