HYDRO-ELECTRIC POWER.

Taranaki Daily News, 21 July 1921, Page 4

HYDRO-ELECTRIC POWER.

PROVISION FOR THE FUTURE. THE NO. 2. TUNNEL. The discussion at Monday night's meeting of the New Plymouth Borough Council on the question of enlarging the No. 2 tunnel at the hydro-electric works elicited divers opinions on the advisability of incurring the extra expenditure. Yesterday Mr. G. A. Lee (of Blair Mason, Lee and Owen, the consulting engineers), when approached by a Daily News representative, briefly reviewed the past steps which had been taken, and he explained at once that the question of how much water was immediately available was not the main feature in considering the extra cost. The provision of a tunnel of larger capacity was being mooted because of future possibilities in getting a bigger water supply. The suggestion originated from the Government electrical engineer (Mr. L. Birks) on his visit to New Plymouth some time ago, and his advocacy was that, seeing there were potentialities of getting further water it might be a good proposition to increase the size of the tunnel, so that irt the future any additional sources which could be tapped might be diverted through the tunnel. The matter was referred to the council, and the consulting engineers said they had 'investigated the proposal sufficiently to form an opinion that the suggestion was bf value and worthy of the council’s consideration. The approximate. cost of increasing the size of the tunnel and other works in connection therewith amounted to £5500. The council decided to inform the engineers that it had no intention of enlarging No. 2 tunnel at present, but the question has since been re-opened. The position was aptly summarised some years ago by the general manager ('Mr. *F. T. Bellringer), who, when remarking that, there were immense possibilities in the proposal, stated: “Once No. 2 tunnel is completed it will not be possible to enlarge it, and other m<ans will have to be taken to meet the demand. It is quite within the bounds of possibility that when the complete scheme (scheme No. 1) is completed the demand will exceed our maximum output, and if provision be not made for the fourth pipe line any extensions to meet the demand will cost many thousands of pounds more than if such provisions be made now, and, indeed, it may be found that the cost will be altogether prohibitive.” The extra expenditure which will be incurred in enlarging the tunnel now is estimated at £5500, representing about five per cent, on the total for the small, r job—really a small proportion. This

would increase the diameter of rhe tunnel by one foot, and made q. of sufficient capacity to cope with further water if likely sources can be secured.

Are there further sources of supply? It is stated by the engineers that investigations of the watersheds of the Waiwakaiho and its tributaries, also the Stony River (which rises in the Pouaki Ranges), lead to the conclusion that it is desirable to make a detailed examination and survey to investigate fully what power is available, whether by storage or the diversion of some of the adjacent schemes into the present csehinent area. In the basia of the Waiwakaiho and Mangamahoe Rivers there arc indications that storage areas can be obtained.