ARAPUNI DAM

Hokitika Guardian, 23 June 1926, Page 1

ARAPUNI DAM

('GLOSSAL UN DERTAKfNG

At, CKI-AXI), June 21. U is Hourly IS months since the Arapoui contract was lot, and a colossal amount of work, particularly hidden "ork, has been accomplished. Xo fewer rhan 550 men are concentrated upon • this Herculean task, many of them working at night on the three shifts a day plan, and work progresses under engineering direction and supervision that is leaving nothing to ehanee. .1 ho main direction in which progress has been made, although it is a. ieatiire of the work that is quite umioticeablo from the edge of the gorge, is the diversion tunnel which is to carry the river waters round the dam site during the construction of the main dam. I his tunnel, which is 24 feet hi diameter, and of far greater ' dimensions than a standard tunnel on the Xew Zealand railways, is now in flic last stages of completion, having ncen lined with concrete, with the exevpti.'.'U ol a, Jew holes, where supporting wooden pillars and joists have I stood, t nrvdng under frowning cliffs, it would already present a clean unobstructed passage for tile river flow, but for the intervention at the intake and exit openings, of a dividing wall of natural rock, which must be blasted away to give admittance to the river. \\ bile every effort has been concentrated upon getting the diversion runnel completed, no time has been lost in pushing ahead with tile wing -.vails ot the gloat dam. The stage reached at present is that while the huge excavations in the cliffs are not quite com pit*tod, a good start Ims been made r.n both banks with construction of concrete abutments. To be exact, 52.000 cubic yards of soil and rock have been I excavated from the flam site, out of an estimated excavation of .54,500 cubic yards, while- 3000 cubic yards have

been removed to make tlie cut off walls., out of an estimated 7300 cubic yards. It will thus be seen that the bulk ol the necessary excavation lias now boon effected. Concreting is also progressing in the cut off walls, or (Tie great vertical saw cuts that run back into the “country” at each end of the dam wall. The concrete for tlie dam is being prepared iii two mixers on the eastern lip of the gorge, and the liquid mixture runs down a line of iron chutes to the foot of tlie cliff. Much has been said about tlie uiiiemilo rope conveyor which brings metal for.concrete mixing from a stone qinrry at A.lukit, up the Waikato River. This extraordinary contraption is working remarkably smoothly and efficiently, considering the cumbersome nature of its machinery. The system is unique for New Zealand, •and is one of the sights for iho curious at Arnpitni. Tlie rope is an endless steel hawser, in two sections, running i ver wheels on huge wooden towers, and weighs no less than To tons. A 60liorse power motor operates the device it each section of the line. Tlie 865 pickets which run on the rope deliver 10 tons of crushed stone in an hour, ia]f of them travelling back to tbo juarry, while Hie others are making heir nine-mile journey to the dam ;ite.