WAITAKI DAM.

Press, Volume LXVII, Issue 20413, 7 December 1931, Page 8

WAITAKI DAM.

♦ harnessing the river. A DIFFICULT WORK. With 1000 men working in three shifts a day, the construction of the dam at tho Waitaki hydro-ejectric works at Kurow, on the border of Canterbury and Otago, has made rapid progress in the past few months. Owing to floods and bad weather, however, it will be impossible for the works to be finished until about the middle of 1933 at tlie earliest —six months or more later than the original estimate. Public finances, too, may check its progress (says the "Evening Post"). Naturo has displayed some of her most capricious moods during man's struggle for supremacy over the turbulent Waitaki river. The colossal task of diverting the swift-flowing stream into half its normal course, and finally harnessing its waters altogether, has already occupied more than two years, and is still far from finished. The greater part of another two years will pass before the turbines are generating power at Waitaki for distribution through Otago and part of Canterbury. Floods and bad weaethcr have delayed the work and hampered tho efforts of the men to build the dam. In February this year a particularly severe "fresh" raised the level of the water suddenly and swept away part of, the works, including a trestle bridge .over which the men travelled from the camp to the workings at the dam. Half of the river was already blocked, and the wall built to a height some feet above the normal level of the water. The speed of the current was naturally increased, and tho flood in tho upper reaches made it race through the narrow channel at a terrific pace. Early ono morning the bridge crashed into tho stream, taking with it part of the equipment used for the workings. This check to tho steady progress that was .then being made meant a vital delay in tho construction of the dam. Like quite a number of southern rivers, tho snow-fed Waitaki is at its lowest level during the winter mgntlis. The engineers had planned to block the second half when the water was low. Tho delay caused by the flood made this im-. possible, and the winter of 1931 went by without the sheet-piling "being driven to the riverbed to stem the current. It mus.t now wait until next winter.

Meanwhile, tho first* half of the wall is boing built up to its full height, and the construction of the power-house on tho other side of the river is steadily going ahead. Test to Dome. The test of the Waitaki works will come when the second half of the river is blocked.- The water will then pass through temporary sluiceways that have been built in the first part of the wall. These sluiceways may or may not carry tho volume of waftr required of them. Their real test will be in the event of a flood. Engineers are confident there will be no trouble. But they cannot tell. As one of them said recently when discussing tho job, "When you are dealing with water you are never quite sure what will happen, nor can you fully appreciate the extent of your opposition. We cannot tell how the Waitaki will behave until we have tested it." The progress that has so far been made at Kurow is regarded by the ,Public Works Department as satisfactory. The most difficult portion of the work has yet to be done. ' ' Problem of Finance. A suggestion has been made that this job will be slowed up, if not suspended, in the near future, owing to the Government's policy of reducing expenditure on Public Works throughout the Dominion. Authority, was given in the session just closed for raising £3,000,000 for Public Works and general purposes. Last year the Government required £9,000,000. The inference from a comparison of the figures is that many Public Works jobs will suffer, and that many men will be transferred from the works in which they are now engaged. Such a policy is almost inevitable, as the Minister for Public Works, the Rt. Hon. J. G. Coates, intimated in his statement' to Parliament a month ago that necessary pruning would bo undertaken throughout the Department. Whether or not the Waitaki hydro works "vfill be slowed up the Department cannot at the present time indicate. "I should think this would be one of the last works to be affected," an offieer of the Department said. "It seems from tho Minister's statement that some economies have to bo made in accordance with the general reducing policy; hut as we are working to a schedule and timing our operations to coincide with seasonal changes, the job at Kurow should, I think, be allowed to proceed until it i 3 absolutely imperative to suspend it." Continuous Work. There are nearly 1000 men working at the Waitaki hydro works at the. present time. Three shifts a day are necessary, because the pumps which keep the seepage water from the workings haveto. be kept going continuously, and the work of building up tho great dam never ceases. All through the night gigantic floodlights illuminate tho construction works. Men crawl like bees about the massvie block of concrete which is slowly but steadily rearing its head skyward. Throughout the day other gangs of men are similarly engaged. Always the work goes on. Next winter, when the level of t.he water is at its lowest, tho sheet piling, will be driven forty feet into the river bed, and the current diverted. If this step is a success the final stage in the work will bo undertaken. It will be impossible to have it finished within the estimated time —the end of 1932 but the Department is hopeful that if the last portion of the dam is' begun in July of next year, the middle of 11)33 should see the scheme ready to operate. Ultimately, the Waitaki scheme will take a great deal of the load now carried from Lake Coleridge, and will send current'through a great part of Otago, joining With the Waipori scheme in supplying power to a great part of the east coast of the South Island.