Clyde Dam ~ The Shocking Facts
- 1973. The Clutha Valley Development Commission was set up to evaluate potential sites, and after drilling test tunnels in the Cromwell Gorge, advised against interfering with known landslide areas which were pronounced highly unstable.
- 1976. The Clutha Valley Advisory Committee, set up by the National Government, advised against the high dam (Scheme F), preferring the low dam option (Scheme H) which would not flood Cromwell, Lowburn, the Cromwell Gorge Highway, and cause landslide issues.
- 1976. The site for the high dam was chosen by politicians, not geologists.
- 1977 April. Ministry of Works' bulldozers moved onto the site and began work, before a Water Right had been obtained and before an environmental impact report.
- 1977 late. The Government applied for a Water Right, and was granted one for the low dam (Scheme H), because the low dam would be less affected by known landslide issues. However, work continued on the high dam (Scheme F).
- 1979 November. Construction work began on the right abutment above the level of the low dam, without a legal Water Right for a high dam.
- 1980. National Government M.P.,Warren Cooper, a strong Clyde high dam and ‘think big’ proponent, announced that NZ would need six or seven dams the size of the Clyde dam by 1995, contrary to evidence of a looming over supply.
- 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.
- 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.
- 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.
- 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 project.
- 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.
- 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 compelling evidence supporting Lensen, he was ignored. He resigned in protest and the issue was covered up.
- 1982. The Government obtained a Water Right through the National Water and Soil Conservation Authority, whose chairman, Bill Young, was also a member of the Government and minister in charge of the project.
- 1982. Landowners appealled to the High Court, citing bias and that the Government did not have a legal Water Right for the Clyde dam, and they won their case.
- 1982. The National Government, under Prime Minister Robert Muldoon, enacted the Clutha Development (Clyde Dam) Empowering Act 1982, controversially over-throwing the High Court decision and a subsequent Planning Tribunal decision against the Government (Annan v National Water and Soil Conservation Authority and Minister of Energy, Gilmore v National Water and Soil Conservation Authority and Minister of Energy), suspending the legal/lawful rights of the individual enshrined in Westminster law, and shocking New Zealanders.
- 1986. Artesian water was discovered in what was previously considered to be dry landslides in the Cromwell Gorge, signalling serious issues with reservoir safety.
- 1986-7. Construction peaked with around 1000 workers on site.
- 1987. New Zealand Electricity Department (NZED) becomes Electricity Corporation of New Zealand (ECNZ / ElectroCorp) - a state-owned enterprise.
- 1987. WorksCorp sold the ‘dam’ to ElectroCorp (ECNZ).
- 1989. April. An intense investigation began into landslide issues, involving up to 40 geologists, revealing large numbers of highly permeable loess underlying large areas of broken rock slides, throughout the gorge.
- 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.
- 1989. ElectroCorp (ECNZ) admitted that they might have to ‘mothball’ the dam because it was fast becoming cost ineffective.
- 1990 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.
- 1990 May. Warren Cooper M.P. denounced recommendations from an international review team of geologists, claiming they were creating “the biggest man-made work scheme on record.” Critics noted that he had been one of the project's leading proponents.
- 1992. Commissioned 1992 (began producing some power).
- 1993. Completed.
- 1994, 23 April. Officially opened.
Prime Minister Robert Muldoon and 'Rob's Mob'- 1996. ElectroCorp (ECNZ) was split into two state-owned enterprises - ECNZ and Contact Energy, the latter controlling the Clyde and Roxburgh dams.
- 1999. Contact Energy was privatized, with 40% purchased by Edison Mission Energy (EME) which subsequently increased its shareholding to 51%.
- 2004. EME onsold its majority shareholding to Origin Energy of Australia, which thereby obtained a controlling interest in one of NZ's largest and most expensive infrastructure assets, originally paid for by NZ taxpayers.
- 2009, May 2. Clyde high dam: “The single most monstrous environmental sin over the last 30 years.” - Michael Cullen, Radio NZ, speaking of his biggest regrets after retiring from the Labour Party. Labour inherited the dam fiasco from the Muldoon government in a snap election in July 1984, called by Muldoon after he had lost the confidence of parliament and New Zealanders. Unfortunately, Labour persevered with the ever-more problematic Clyde dam, and after National became the government in 1990, the 'monstrous environmental sin' was completed.
