DOUBLING THE WATER SUPPLY

Dominion, Volume 9, Issue 2859, 25 August 1916, Page 6

DOUBLING THE WATER SUPPLY

Sir,—Seoing, tho Wellington City Council haye a promise from the State, that a further portion of the waste lands in the vicinity of the Wainui-o-rnata water -shed. will be conserved, by which means the present water supply can be augmented, and noting also that the Mayor contemplates some fur-' ther action in this matter, I am prompted to write on this subject. My only excuse 'is the knowledge I possess of tho locality, from which the proposed, additional , supply - of-", water for the City, is to be.obtained. . There seems to be some misconception as to the quantity of.water tp.be obtained by a tunnel through the hill from the Upper, Wainui-o-mata Valley to the left branch or tributary of the Orongorongo. The: area of catchment, and volume of water obtainable from that locality, seem to be much overstated, unless it were'possible, to tap the Orongorongo, stream! much lower down that valley, in which; case it could not be brought into tho present reservoir by natural gravita-. tion. ,

.. In _ order to give some idea of tho locality,- I-have prepared a rough pen and ink sketch of the upper portion of tho Wainui-o-mata catchment area, and also .the portion,of the Orongorongo which, lies between the'present' catchment area and' the Waiorongomai Valley. This bird's-eye sketch is not prepared from any data or to any scale, having no particulars for' the purpose, hut is to be taken as a rough' idea .of the lay of the hills and valleys in that direction. If the small tunnel or drivel were put through, as shown on the sketch A.to B, a fair stream of water could ho diverted through the low saddle in the. dividing range. The City l Counoil should have the, data or particulars of this proposed, tunnel,;- in 1 the Borough Office, as the same was furnished by myself to Mr. Longhfey,. the'then .'Citv Engineer, about 30 years ago. Should this work be carried, out at a small outlay, it would augment, hilt by no means double, the supply.; the supply of water might be further slightly increased hv a nice cut round the base of tho .hill (Whaleback), as indicated on sketch from B to C. This small work could be done while surveys and other particulars were being obtained, If possible for a larger scheme of supply. In the left tributary of the Orongorongo there is a piece of fairly flat land, where five sections of about 100 acres each were surveyed for the New Zealand Land Company bv one of their surveyors, H.-S. Tiffin. The land is hiirh, cold, and part swamny, of poor quality,'covered in dense bush (subAlpine), the timber beinf principally birch (Nothofagus Solandri and *< T . Menziesii). with much tawhere' CWeiumannia Silvicola), and.other timber. The enclosed sketch might be useful as a guide to the Mayor and Citv Fathers when they are in want of a little exorcise, or desirous o 5 having an "outing," or to spend an Easter holidav.—T am, etc., '-, ' D. SINCLAIR. Pnlmerston North.. ; [We shall be pleased to forward the plan enclosed by our correspondent to Mr. J. P. Luke, who'no doubt will give our correspondent's suggestion due consideration.]