Waitaki Hydro Scheme
Meridian Energy’s Waitaki hydro scheme produces electricity using water and snow from catchments within the Southern Alps.
Its eight power stations are in a chain so each volume of water can be used to produce electricity up to eight times.
– The upper Waitaki
– The mid Waitaki
– More than 100 resource consents
The upper Waitaki
In the upper Waitaki water is passed from storage lakes through canals to each power station.
Power stations
– Tekapo A
– Tekapo B
– Ohau A
– Ohau B & C
Canals
A major feature of the upper Waitaki hydro scheme is the canals which help combine the resources of Lakes Tekapo, Pukaki and Ohau.
These canals have a total length of more than 58 kilometres. Their construction required the excavation of nearly 45 million cubic meters of spoil.
The canals allow fishing all year round. The Tekapo canal contains a Sockeye salmon farm while the Ohau C canal has a Chinook salmon farm.
| Canal | Length (km) | With (metres) | Depth (metres) | Peak Flow (m3/s) |
| Tekapo Canal | 26.5 | 39.6 | 5.3 | 130 |
| Pukaki Canal | 12.0 | 80.4 | 10.1 | 560 |
| Ohau Canal | 8.4 | 63.5 | 5.8 | 200 |
| Ohau Canal A | 1.0 | 97.0 | 12.0 | 560 |
| Ohau Canal B | 2.8 | 97.6 | 10.1 | 560 |
| Ohau Canal C | 7.3 | 97.6 | 10.1 | 560 |
The dams
There are two dams on the upper Waitaki, the Pukaki high dam and the Ruataniwha dam.
The mid Waitaki
The mid Waitaki power stations discharge water back into the Waitaki River which then forms a storage lake for the next station in the chain.
Mid Waitaki
The three power stations are
– Benmore
– Aviemore and
– Waitaki.
More than 100 resource consents
Meridian Energy holds more than 100 resource consents for the operation of the Waitaki power scheme.
These consents provide for the taking, damming, diversion and discharge of water throughout the scheme. They are supported by conditions and our „Operating Rules“ which both describe in detail how we operate the power scheme.
Meridian also holds other consents for ancillary operations supporting the scheme including erosion protection works, sewerage facilities and bore-holes near our dams used for surveillance monitoring of dam structures.
Hydro power station statistics
| Power Station | Nominal Annual Generation (GWh) | Which equals enough power to supply |
| Tekapo A | 160 | Dunedin for 2 1/4 Month |
| Tekapo B | 800 | Dunedin for 11 1/2 Month |
| Ohau A | 1150 | Dunedin for 16 Month |
| Ohau B | 970 | Dunedin for 14 Month |
| Ohau C | 970 | Dunedin for 14 Month |
| Benmore | 2200 | Christchurch for 10 Month |
| Aviemore | 900 | Dunedin for 13 Month |
| Waitaki | 500 | Dunedin for 13 Month |