THE SNOWY MOUNTAIN PROJECT

Press, Volume C, Issue 29602, 26 August 1961, Page 8

THE SNOWY MOUNTAIN PROJECT

Second Stage In Vast Scheme {Commonwealth of Australia New* and Information Service} the calling of world-wide tenders for a 150 ft.-high dam and a 15-miie tunnel, the second major phase of the £400,000,000 Snowy Mountains Hydro-Electric Project, in south-eastern Australia, is about to begin. The project, which was launched in 1949 and is expected to be finished in 1975, is designed to conserve, and divert, the snow and river waters of the Snowy Mountains area for use in irrigation and power generation. The over-all scheme, the largest integrated project of its kind in the world, involves vast construction, including nine major dams and a number of smaller dams, 10 power stations, more than 100 miles of tunnels, about 80 miles of aqueducts and several hundred miles of mountain roads.

In the first major phase, now nearing completion. £A180,000.000 has been spent. Seven dams, two power stations, some 50 miles of tunnels. 29 miles of aqueducts, 290 miles of transmission lines and 500 miles of roads -have been built. Men from some 40 nations, at the rate of about 5000 at a time, have forked on the project, overcoming innumerable problems and hardships created by the rugged terrain and by the rigours of the climate in the Snowy Mountains area. In spite of the difficulties, work on the project has kept to, or often ahead of. schedule. Some 50 miles of tunnels. 29 miles of aqueducts. 290 miles of transmission lines and 500 miles of mountain roads have been built. Construction towns have been put up, and one permanent town. Adamineby, has .been moved in toto a distance of about six miles to make way for the vast Eucumbene dam. The Snowy Mountains, in which the work of the project is going on, are Australia’s highest peaks and its main single source of water. They rise to 7314 feet and cover an area of some 100 miles in length by 30 to 50 miles in width. In these mountains are the headwaters of Australia's two largest rivers—the Murray and the Murrumbidgee—and on them falls almost the only regular snows of the warm, dry mainland of Australia.

Broad Concept The broad concept of the Snowy Mountains project is to conserve these snow waters and to divert the third major stream ih the area—the Snowy—which now flows south-east through an area of adequate rainfail, so that its waters will flow west through the Murray and Murrumbidgee systems to the fertile, but dry, farmlands of the interior. The other major aim of the project is to generate electricity. Why such a great undertaking should be attempted in such rugged area by a nation of only 10,500.000 people may be better understood when it is realised that the total water run-off of the entire continent represents less than half the flow of the Mississippi river. Or, present estimates the full project wifi be completed in 1975. By then the system will provide annually nearly 2.000.000 acre feet of water and will have an. annual power output of over 5.000,000.000 kilowatt hours. This will increase Australia’s current total electrical-power output by 30 per cent.

The difficulties which faced the Snowy Mountains Hydro-Electric Authority, when it was first established by the Federal Government in July. 1949, seemed almost insuperable. The mountainous country in which it was to work was some of the wildest in Australia. Many of the deep gullies and gorges were unexplored. The topographical information available was based on meagre survey, geological and hydrological data. The sub-surface structure and composition were virtually unknown.

Men From Forty Nations An added problem was that Australia lacked the large number of engineers, scientists, accountants, technicians and skilled workers needed for such an additional project. A world-wide recruiting campaign was organised to overcome this and, since 1949, men of more than 40 nations have worked together on the Snowy. The work force at any one time is about 5000 meh. How successfully these men have worked together can be judged by the fact that almost every undertaking has been completed well ahead of schedule. Hie build-

ing of the Eucumbene dam, one of the highest earth and rock filled dams in the world, was finished in two years—two years ahead of schedule. The dam, which rises to a height of almost 400 feet, is almost half a mile thick at the base, and banks up a gross capacity of 3.850,000 acre feet of water, was built bv the American group of Kaiser - Walsh - Perini - Raymond employing Australian and New. Australian workmen. The same group, driving the 14-mile long, 24-f<-et diameter EucumbeneTumut tunnel westward from the dam to the Tpmut river increased the rate of tunnelling through hard rock from the then recognised Australian figure of 70 feet a six-day working week to 484 feet a six-day week. Later an Australian firm. Theiss Bros. Pty., Ltd., drilling a nine-male tunnel from the Tooma dam to the Tumut Pond dam, set what was believed to be a world record by advancing at the rate of 525 feet in a six-day week.

More recently, Utah Australia, Ltd., and Brown and Root Sudamericana, Ltd., an American contracting group, in constructing tme Tan’.angara dam and the 10}-males Murrumbidigee - Eucumbene tunnel established a world record in drivmg 590 feet in a six-day working week. Work on surface projects, too, has gone ahead at extraordinary speed despite great difficulties with terrain and climate.

Many Problems Many problems, for example, faced the engineers responsible for putting in the transmission lines that carry power from the Snowy to the electrical networks in the" States of Victoria and New South Wales. The Upper Tumut switching station had to be linked with 330,000-volt transmission lines to a Victorian Electricity Commission sub-station 105 miles to the south-west and with an Electricity Commission of New South Wales sub-station 90 miles to the north. Most of the country to be traversed was heavily timbered, criss-crossed with deep ravines and subject to below freezing temperatures in winter and near century readings in summer. Line surveyors had to hack their way through thick undergrowth in areas never before visited by man. Above 4000 ft heavy icing in winter created problems. Cables being used at lower altitudes proved unsatisfactory and special aluminium alloy had to be imported from England so that a” cable that could stand altitude and icing could be devised. But in spite of al! the setbacks, one of the contractors building the transmission lines, an Italian firm, Electric Power Transmission Proprietary, Ltd., progressed at an amazing rate. Gangs of 11 men averaged the erection of two specially-designed 55ft towers a day, and four spans a day were strung with six cables. The towers were erected on their sites, each piece being bolted together like a child’s structural set.

The Snowy Mountains project is being financed by the Australian Federal Government, working through the Snowy Mountains HydroElectiricity Authority. No charge will be made to the States for the water which will provide irrigation for three States—Victoria, New South Wales, and South Australia—but the two States which use the electric power, Victoria and New South Wales, will pay for it. By the sale of power at competitive prices the authority can meet all the costs of the project.

Power Already Delivered As eadh part of the Snowy project is completed it goes into immediate use. Two power stations, Guthega (capacity 60,000 kw) and Tumut I (320.000 kw) have been delivering power for several years and another major station, Tumut 11, will begin deliveries as soon as it is completed at the end of this year or early next year. Originally the project was planned as two more or less separate systems, but as work progressed and the Authority gained in knowledge of the area, a major amendment was made and the two systems will now be linked by the 15-miles EucumbeneSnowy tunnel for which tenders have recently been called.

The complete integration of the scheme has many advantages, speeding its completion, making it more flexible and making it possible for water and power to be regulated at will-throughout the vast network of the project. Undoubtedly the second half of the work, which will begin after contracts have been let in November, will bring with it a host of problems. But Australians, immensely proud of the project and of its progress so far, have no doubt they will be solved as effectively as even greater'initial problems have been solved on the Snowy over the past 12 years.