MORE WATER FOR CITY

Sun (Auckland), Volume III, Issue 872, 16 January 1930, Page 10

MORE WATER FOR CITY

COUNCIL INSPECTS HUNUA STREAMS 40,000,000 GALLONS DAILY Looking to the day—perhaps in the not very distant future —when Auckland's growth of population will embarass the city’s existing water supply, a party of 40, consisting of members of the City Council and officials, yesterday inspected two streams in the Hunua Ranges. Although nothing definite has yet been decided about bringing in this source of supply, a great deal of preliminary information has been gathered for the council by various experts, and this was explained to the party by Mr. A. D. Mead, city waterworks engineer, Mr. A. J. Entrican, chairman of the Water Committee, and others. The council has had the idea of harnessing the Mangatawhiri and the Mangatangi streams in view for some time. Both waters empty into the Waikato River, and together they have been discharging, the wet season being taken into account, a daily flow of 42,000,000 gallons. The Mangatawhiri has a volume of 14,000,000 gallons daily, and the Mangatangi 25,000,000 gallons. Even in the very dry sutnmer of two years ago the combined flow was never lower than 11,000,000 gallons a day, which is rather more than the summer daily consumption of the whole city at the present population. Toward the head of the Mangatawhiri Valley experts estimate that a dam 70ft high would impound 1,400,000,000 gallons. The council’s advisers are now, however, favouring a site about three-quarters of a mile lower down where the valley is much narrower, and where an even larger amount of water could be stored by a dam of similar height. More private property would have to ,be purchased for tile lower site, but in all probability the saving in the cost of dam construction would more than pay for this. From the two streams it is estimated that a permanent daily supply could be developed, yielding 24,000,000 gallons at the most unfavourable time of the year. The whole scheme would include two large tunnels, one about a mile in length, bringing the waters of the Mangatangi through under the range that separates it from the Mangatawhiri, and the other about miles in length through under the Moumoukai Hill, connecting the Mangatawhiri Valley with the Hunua Valley. s