HORAHORA POWER SUPPLY.

Putaruru Press, Volume VI, Issue 232, 12 April 1928, Page 1

HORAHORA POWER SUPPLY.

NOW. ALMOST NORMAL. Question ot Silting. rosiJe.n Explained to Board. The Thames Valley Power Board has not been taking the continued power stoppages lying down, as many consumers have apparently imagined, but has been most active in its representations to the Department to

secure a continuity of supply in its area. No stone has been left unturned to secure all available information concerning progress at Arapuni and its effect on Hcrahora, and the chairman and executive officers have been in constant touch with the Department’s officers at both works, while several trips of inspection have been made. At the March meeting the position was discussed very fully by the board, and concern was expressed at the number and duration of the interruptions. A reply to a request for further information from the electrical branch of the Public Works Department was before the board on Monday.

“ The power supply from Horahora has been almost normal for the past six weeks, with a maximum load of about 10,500 k.w. during the dry weather,” stated the Department. u The Power house is taking practically all the water in the river, and the increased flow during the recent wet weather has enabled us to carry increased load. The interruptions due to trouble at Horahora were six in the first four weeks (since January 15) and none in the last three weeks, apart from shutdowns on Sundays, and the longest interruption from this cause was of IS minutes’ duration.

“ As regards closing down at night instead of on Sunday, I regret we cannot undertake to do this. When we close down we have from 40 to 50 men working, most of them in the water, and the risk of confusion and accident is too great for this work to be done at night. “ With reference to steps being taken to minimise silting up of the head race during the rainy season, excessive silting of the headrace will not occur as long as we are able to keep the screens clear and maintain the flow in the race. The amount of silt now passing through the turbines daily, if it were deposited in the race, would be sufficient to fill it with silt in about ten days. The amount of silt now in the race is equivalent to about three feet depth over the whole area, and this amount has not varied much during the past six weeks. The flow in the race has also been steady for the past six weeks, and it is to be expected that for any flow ir, the race there would be a corresponding amount of silt deposited, until a state of equilibrium is reached, at which the amount of silt brought into the race is equal to the amount carried through the turbines. As far as the silt is concerned, the position will be improved when the Waikato river rises, because we shall then be able to discharge water and silt through the gates in the weir, which will enable the area of water above the weir to be cleared of silt. It is probable, however, that at periods of high water in the rainy season considerably' more pumice and debris will be brought down, and there will be increased difficulty in keeping the screens clear.

“ The whole matter has been given a lot of consideration, but it does not appear practicable to deal with the pumice and debris in any way and other than we are doing, which is to let it come on the screens and remove it from there.”