The Small Dams of Central Otago

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The Small Dams of Central Otago

Ellis.jpg
David Ellis 2009 Privately published, Alexandra. 156pp

ISBN 978-0-908960-53-8 Available through IPENZ / New Zealand Society on Large Dams here.



The Blurb: “A history of the small dams that were built to provide irrigation and electricity for people of the area”.

Mini Review

This is a POP page.
It represents a Personal OPinion.
That opinion is the sole responsiblity of the author and not the website!



Alexandra resident D G Ellis is a former General Manager of the Otago Central Electric Power Board and earlier Assistant Engineer to the Board under his father Engineer-Manager. His book concentrates on the schemes built for power and / or irrigation, rather than the dams of the gold-mining days, though the power from the earlier of those covered here was used in the later dredges.

Central Otago is fortunate in the attention that has been given to its engineering heritage. The dredges[1] and their early power schemes have been well covered[2]. The extraordinary story of the Alexandra and district water supply for gold and for the town and around has been well told by McCraw[3].

This is a valuable addition to these. Ellis had access to many pictures of the dams in construction and being tested by floods, so his book is extraordinarily rich in these. It is a mine-able source for the methods of dam construction of the past, the details of bypasses and releases. Not that all the dams are old. One dam is of roller compacted concrete - a new technique and one as yet rare in New Zealand. There are some pictures too of remains from their construction so there is a bit archaeology here. Most of the dams are concrete arch dams - suitable for the geology and reflecting how far aggregate for concrete had to be brought. The roller compacted concrete dam is of schist, so this was another way around the problem. One other is of concrete faced rockfill, again a rare form here.

As well as modern and historic photographs there are lots of engineering drawings - and perhaps some which a lay person would struggle with - but an engineer will love them. Good to see the designers and builders credited fully, but the story is a bit lifeless at times. His other account[4] which this reviewer has not seen may well have some of this - but a bit more would have been welcome here.

A book for archaeologists and historians of civil engineering heritage for sure.

GL


References

  1. Hearn, T J and Hargreaves, R P 1985 The Speculator's Dream, Gold Dredging in Southern New Zealand. Allied Press.
  2. Chandler, P M and R C Hall 1986 Let There Be Light. Otago Central Electric Power Board.
  3. McCraw, J.D. 2000 Mountain Water and River Gold. Square One Press, Dunedin.
  4. Ellis, D 2005 Electricity in Central Otago, 1922-1990: an account of the people who brought electricity to the homes and work places of Central Otago under the elected power board system. Privately Published Alexandra.