THE NEW MAIN

Evening Post, Volume CIX, Issue 115, 19 May 1925, Page 7

THE NEW MAIN

REGULAR DELIVERIES FROM NOW ON

LORRY WORK IN BUSH

The regular delivery of the 21-inch steel pipes for the Orongorongo-Karori main has now been commenced by the contracting company, and, unless the unexpected happens, the supply should be maintained steadily.

The total length of the new main will be, roughly, 21 miles, and of this length' 2^ miles or thereabouts of pipes are already laid, from the Orongorongo intake chamber, through the tunnel to the Wainui portal of the tunnel; over 17 miles of main have therefore yet to be laid. It is a big job, but the council's officers are hopeful that it may be completed well within twelve months, possibly by next summer or autumn. The company is sanguine of being able to turn out the pipes quite as rapidly, pro bably more rapidly, than the council can lay them, now' that it has, after several months' delay and worry, mustered all the plant required for "their manufacture.

The council is anxious that all the pipes required for the first length of main from the Wainui end of the tunnel and down the valley to the Wa'iwetu hill shall be delivered as early as possible, as the cartage of heavy and awkward lengths of pipe over the hill and valley roads in midwinter is likely to be very heavy going. Just over two miles of hand-cut trench is immediately ready for the laying of the main through the waterworks reserve at Waimii, country in which a mechanical' trencher could scarcely work. This trenching, probably, represents the slowest part of the necessary excavation work, as mechanical means will be employed over-by far the greater length of the remaining 14 or 15 miles to the Karori reservoir. Apart from any altruistic desire to supply water to citizens, the council is particularly desirous of supplying ample water at the earliest possible date to Karori and Onslow, that returns may be had from the £200,000 or so sunk in the ground iv the shape of reticulation services. As has already been stated, temporary measures have been taken to supply n modorate flow of water to the greater part. c{ tlw» Karori district from the Northland and Kclburn reservoirs, but it is not suggested that this supply is anything more than" an expedient to fill a gap. HEAVY GRADES AND PINCHES.

Just, at the present time the pipe company is delivering under difficulties, right to the head of the small and dense-ly-bushed creek running up to the tunnel portal. A bush road, in very good order as a bush road, runs on up pastthe Morton dam to this point, but bush roads are not necessarily designed for heavy lorry transport. Thorn are heavy grades and pinches, and there is remarkably little manoeuvring room, but, fortunately, the length is short and the going will be fairly easy when this 'section, of delivery is' completed. As the longer lengths weigh something like a ton, it is very necessary' that they are dumped from the lorries at the spots at which they are to be laid. Through the bush two or three lengths appear to constitute a full load, but when the going is more open five or sis may be taken out at once.

If the new main can be laid by next smnmer Wellington's worries over a water shortage should be over for the time being, but the Orongorongo stream is not the last word in the city's' water supply, and it will-not be' many years before a. scheme suggested by the late Mr. Morton for the building of a third dam in the Waimii Valley, to hold 800,000,000 gallons; will be again considered. In fact, it has been considered in the cutting of the trenches for the new main, for the new line and road run along the hillside high above the present valley road, which will be submerged under many feet of water when the hi.^c dam is built.