NEW WATERWORKS RESERVE

Dominion, Volume 21, Issue 128, 28 February 1928, Page 8

NEW WATERWORKS RESERVE

ENGINEERS ESTIMATING RESOURCES One of the first visible results of the inauguration of the new scheme for the supply of water to the Wellington district from the tributaries of the Hutt River is now to be seen on the banks of the Wakatikei, a stream familiar to Wellington anglers. Here Mr. A. K. Campbell (under Dlr. J. M. Morice, who was engaged by the board controlling the reserve to investigate its resources) and several assistants, have established a camp for the purpose of measuring the flow of water past a likely dam site. Although one side of the Wakatikei Valley has been denuded of forest and now grows chiefly fern and biddi-bids, the side nearer Akatarawa is covered with dense bush and even after such a dry season as the present the stream contains a considerable volume of water, wfiich could, no doubt, be greatly increased before the scheme is developed many years hence by proper afforestation. The spot chosen as likely to be a good one for a dam cannot fail to impress even those ignorant of engineering, for at this place the walls of the valley are only about forty feet apart at the bottom and are said to be likely to provide good foundations. Above this the valley widens out with a flat floor, and converted into a lake by the comparatively small dam, could store an enormous quantity of water. The method of guaging the stream is to build a little dam of boards with a weir in one part. All the water that can be induced to do so flows over the weir. Twice daily the height of water over the weir is measured, and from this measurement the amount of water flowing can be calculated. The work is done in the summer so that the minimum flow is measured. The Wakatikei is only one of several streams in the new reserve, and it has been suggested that the intervening hills be pierced with tunnels so that one dam could store water from more than one supply, as was at first intended at Orongorongo. From the hills high above the Wakatikei can be seen ridge after ridge of virgin forest and it is hard to imagine the city and district ever outgrowing its present developed and undeveloped sources of water supply.