HYDRO-ELECTRIC SCHEME.

Otago Witness, Issue 3869, 8 May 1928, Page 76

HYDRO-ELECTRIC SCHEME.

THE WAITAKI DAM.

SITE DEFINITELY CHOSEN. AUCKLAND, May 1. After a detailed survey and test work extending over the past two and a-half years, the Public Works Department has definitely chosen a site on the Waitaki River (Canterbury), about four miles above Kurow railway station, for a large hydro-electric scheme to supply Soutn Canterbury and North Otago. It is estimated that the station, which will take about three years to complete, will have a capacity equal to that of Arapuni, namely, 150,000 horsepower. Complete development of the scheme is estimated to cost £1,200,000, although the initial expenditure will be reduced to probably £1,000,000 by omitting certain work not immediately necessary. Reference to the scheme was made by Mr F. W. Furkert (engineer-in-chief to the Public Works Department) on his return from Whangarei to-night. He stated that Mr R. H. Packwood, who had been in charge of the Westfield railway deviation since the commencement of the work, would leave for the south, probably this week, to supervise the Waitaki scheme. Mr Furkert added that the question of providing adequate supplies of power for Canterbury had been considered for many years. Many proposals had received attention since a thorough investigation of potential water power supplies had been made by Mr P. S. Hay in 1901, and until recently it was thought best to secure power from the iakes feeding the Waitaki River, chiefly Lake Tekapo. The chief objection to this was that the lakes were remote from the consuming centres, and, in addition, heavy expense Would be entailed in constructing transmission lines, as well as carting material. The scheme now to be undertaken was regarded as the most satisfactory one, the advantage being that the proposed site of the works was accessible. The works would consist almost entirely of a dam across the Waitaki River, raising the level by about 70ft. The power-house would be built into one end of this structure, and the balance, about 1360 ft long, would be used to discharge surplus and flood waters. Of the total length of 1700 ft of dam, about 500 ft only would be in the actual river channel, the balance being about 40ft in height and built in : the dry of the banks. There was a huge flow in the river, and the new works would be .capable oi generating a supply to meet demands over a wide area for many years to come. If ever more power were required than could be secured from the rivgr at present, it would always be possible to increase the storage capacity of Lakes Ohau, Tekapo, and Pukaki, the latter,of which was fed from the Tasman Glacier. In any case there was almost twice as much water available as in the Waikato River. Two units each of 20,000 kilowatts capacity, or. two each of 15,000 kilowatts, would be installed on the completion of the dam, however, by building subsequent low control dams at each of the lakes. The capacity of the station could be increased to 70,000 kilowatts on a 50 per cent, load factor. A basis for further power voltage above and below the station could be developed on the river without interfering with the station’s output. The new station will not only supply South Canterbury and North Otago, but will meet with the Lake Coleridge system at a point to be determined by their mutual loads. Mr Furkett added, “ When Christchurch requires all the power that Lake Coleridge can supply, which may occur at some date not far . distant, the Waitaki supply will reach almost to the city. Eventually there will be a connection between lines from Waitaki. Coleridge, and Dunedin. When this is accomplished the system will be very much more reliable, and - on the interruption of one service, the other two will be able to provide additional power.” The undertaking was comparable to the Arapuni scheme in importance. The power demand in the various districts had become so great that a start was necessary and work would be commenced at an early date.