Maraetai Hydro Works

Grey River Argus, 7 October 1948, Page 7

Maraetai Hydro Works

AUCKLAND, Oct. G The 50-ton gate for the Maraetai diversion tunnel and its guide frame, weighing about another ten tons, have received their final inspection by Works Department engineers in Auckland before being dismantled for the journey by road or rail to Mangapm?t largely by private contracts at a n B AuckS y en y gi!?eenn E works, the Kths a "to eon™e e te. h They'are’ vtai Srts in the building of the new hydro-electric scheme on the Waika square and more than 3!t Ab in 1 tSnels the gate itseK b macle of strong steel gnders faced with 5-Bin thick plate.lt runs in its frame, which will be c o in tn a vertical shaft, on stamiesa steel rollers which bear on a track of aluminium bronze. This surface is machinedl to an ac euracv of. a few thousandths of an inch 7 A rubber seal around the sate is designed to ensuie that , W The gate wil mot be used until the &?We%dV°he P dm«stontun. nel through which the Waikato River will have been running for more than a year. When the tunnel is closed the new lake will bank up behind the the gate the tunnel will be plugged, and the gate can then be raised and used again to close the tunnel In the Whakamaru hydroplpctric scheme, which will tnen oi in the process of construction a few miles up the river.