RIVER FLOWS

Evening Post, Volume CIX, Issue 101, 1 May 1930, Page 11

RIVER FLOWS

EESULTS OF GAUGINGS

EFFECT OF DRY SPELL

The City Engineer (Mr. Hart) reported to the Water Board yesterday that continuous gauging had been carried out on the streams under the board's control, which included the period of the-minimum yearly flow. The 'watershed survey of the Hutt Eivor which ho had been instructed by the board to put in hand had been commenced, and it was hoped to have this completed in about six weeks' timo. "In regard to the construction survey of the main Hutt scheme which I was instructed by the board to put ia hand last September, this has been continued throughout, and is the subject of a special report I am forwarding to the board," stated Mr. Hart. The "Waterworks Engineer (Mr. M'Killop) said that the' lowest flow of the Hutt Eiver was 19,000,000 gallons during the past year. The Wainui was down to about 4,000,000 gallons flow, the Orongorongo to about 3,750,000 gallons, the Whakatikei to 5,000,000 gallons, and, the Little Akatarawa to 4,500,000 gallons. ' Mr. Troup: "The minimum we may expect is a long way below that." Mr. M'Killop agreed that the year was not one of the dryest, as the Wainui in 1917 was as low as 2,000,000 gallons, an actual test gauged by the late Mr. Moriee. In 1928 its flow was not below 4,000,000 gallons. Mr. Troup pointed out that, taking the same proportion of drop for the Hutt Eiver, the 19,000,000 gallons would shrink in a really dry year to 10,000j000 gallons. . . ■- : - The City Engineer said that it was remarkable that, although the drought had continued for such a long period, the water had never been 12 inches below the lip of the Morton dam weir. Supplies had been drawn from" the Orongorongo direct to the city. Mr. M'Killop said that a surplus from the Orongorongo could be stored in the Wainui dam if necessary, but Mr. Troup pointed out that the Orongorongo went short before the Wainui. One reason why the water had held out so well, said Mr. M'Killop, was that the middle of the summer wa3 wet, restoring the ground water storage. The drought thus came too late to be really felt. The City Engineer: "We may rely on getting 10,000,000 gallons from the Hutt Eiver at any time." .