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they chose where to build it
The site for the high dam was chosen by politicians, not geologists. -
the govermant approved the construction
- 1981 July. The Government approved the construction of the high dam despite still not having a legal Water Right, and previous warnings regarding gorge instability.
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they didnt need it
- 1981. It was realized that there was an over production of electricity and that the dam, especially Scheme F, was not required. Construction continued mainly to keep the work force employed.
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they had to pay more
- 1981 December. The Government put the Clyde dam project out to tender. Seven tenders were received. The Ministry of Works originally tendered at $156.4 million, later revising this to $117.3 million.
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more people
- 1982, April. The Clyde Dam construction contract was awarded to a joint venture of W Williamson & Co of Christchurch and Ed Zublin AG of Stuttgart, West Germany. The winning bid was $102.6 million. Zublins were partnered with Williams Construction of Christchurch as ‘window dressing’ (2.5% of the partnership). The so-called joint venture was plagued with industrial disputes throughout the contract. Their workers also suffered more accidents than workers employed by other contractors on the pro
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something went rong
- 1982. Workers discovered a faultline directly under the dam and spillways. (The River Channel Fault branching from the main Cairnmuir-Dunstan Fault crossing the gorge 3kms above the dam.) Vast amounts of slurry concrete were pumped into tunnels across the fault called “shear pins” to supposedly lock the fault, even though the fault was 12-15kms deep and such “dental concrete” would be instantly broken in a large earthquake.
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re-designed
- 1982. The dam was re-designed with a controversial “slip-joint,” supposedly allowing 2 metres of lateral movement, and 1 metre of vertical movement. Geological evidence showed much greater movements had occured and are possible, up to 9 metres laterally! Even more alarming, one of New Zealand's leading geotechnical scientists, Gerald Lensen, warned that the River Channel Fault was a secondary "tensional fault" (expanding), and therefore the "slip-joint" was NOT designed correctly. Despite comp
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a risk
- 1988 March. Serious gorge stabilisation issues were admitted, and it was announced that the project could not be commissioned without another $337 million being spent on landslide mitigation to reduce, but not remove the risks.
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they addmited
- 1989. It was realized that the 1982 re-design had omitted one of the two sluice gates. A work-around was designed costing $2 million, reducing the dams generating capacity by nearly a third from 612 MW to 432 MW.
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it started up!!
- 1992. Commissioned 1992 (began producing some power).
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complet!
it was completed! -
open !
- 1994, 23 April. Officially opened.
