Waitaki Dam

The Waitaki dam and power station was a „make work“ construction project during the 1930s Depression.

The construction camp was the birthplace of New Zealand’s social security and welfare Systems.
Construction began in 1928; the dam was constructed in two parts.
First a coffer dam was built which diverted water to the Otago side of the river channel allowing the building of the Canterbury side of the dam which incorporated 11 sluice gates. These gates then allowed water to pass through while the Otago side of the dam was constructed.
The gates were then closed and concrete was poured behind them.
The dam was the last in New Zealand to be constructed without modern machinery.
More than half-a-million cubic metres of material was excavated using picks and shovels. Steam powered pumps were used to keep excavations dry.
The section of the dam between the powerhouse and the Canterbury side of the river acts as a 354 metre-long ungated spillweir which can cope with a flow of 6,740 cubic metres per second (the mean flow of the river is 350 cubic metres per second).
Early in 1935 the station had two 15 megawatt generators operating, enough to meet nearly half the electricity needs of the South Island at the time.
Three more generators were added and in the late 40s to early 50s the powerhouse was extended to accommodate two more generators.

Key statistics
– The dam contains a total of 173,000 cubic metres of concrete
– Nominal annual generation: 500 GWh
– Installed capacity: 105 MW