ARAPUNI DAM.

Press, Volume LXVI, Issue 19862, 25 February 1930, Page 10

ARAPUNI DAM.

EROSION AT SPILLWAY. PROGRESS OF DIVERSION WORK. [THE PRESS Special Service.J AUCKLAND. February 24. ''There lias been 110 appreciable erosion at Arapuni spillway since the occurrence in August," sa.d the Minister for Public Works (the Hon. E. A. Ransom) to-day. "I am very gratified to know that such is the case, and given another month or two, we should he able to divert enough water through the penstock tunnels to enable a careful examination of the spillway to be made." The' Minister said the recent test of the by-pass tunnel had proved very satisfactory, although it was not intended to put water through that tunnel unless absolutely necessary. The penstock tunnels known as Nos. 7 and 8 had been driven with the object of taking the surplus water, and he had been advised that those two tunnels, together wi'th the three penstock tunnels used for operating the three units at the power-house, would practically take the normal flow of the Waikato river. If there was any water in excess of that dealt with by those five tunnels, it would be necessary to use the by-pass tunnel.

"Until we get' the spillway area dry we do not know the precise nature of tho work that will have to be undertaken," added the Minister. ''A thorough examination of the waterfall will then be undertaken. The present idea is that it will probably be necessary to concrete the spillway. We had expected to pass water through the penstock tunnels Nos. 7 and S in March, but a weakness developed in one of the faces above the penstock tunnels on the power-house side. That face is being brought down and that work will conseouentlv delav a little the task ot diverting water from the spillway, shifts are being employed on Tie work of bringing down the face and the excavation thus made will be useful when the time comes for an extension of the power-house."