Waitaki dam powerhouse and wall. Photo RNZ/Ian Telfer. More photos of the Waitaki Dam.
The Waitaki hydroelectric dam in North Otago was completed in 1935, the last New Zealand dam to be built using pick, shovel and wheelbarrow. Eighty years on, the dam is getting a 40 million dollar upgrade.
Meridian Energy says the Waitaki Dam complex is being strenghtened to keep operating through a major earthquake. One of the dam's seven generators is being repaired and its drainage systems improved.
Meridian's strategic assets manager, Richard Griffiths, says some of the most important work is adding flexibility to the dam's powerhouse building roof, so it can withstand a major quake.
He says the dam should keep generating power through a one-in-two-and-a-half-thousand year quake.
Mr Griffiths says the upgrade has shown how well the dam wall was designed and built, especially given it was all done by hand.
Reporter Ian Telfer went exploring...
Inside one of the dam turbine scroll chambers (where the water goes normally), which are being stripped and restored. Photo RNZ/Ian Telfer.