Review Lecture: The Snowy Mountains Hydroelectric and Irrigation Scheme (Australia)

Review Lecture: The Snowy Mountains Hydroelectric and Irrigation Scheme (Australia)Author(s): William HudsonSource: Proceedings of the Royal Society of London. Series A, Mathematical and PhysicalSciences, Vol. 326, No. 1564 (Dec. 21, 1971), pp. 23-37Published by: The Royal SocietyStable URL: http://www.jstor.org/stable/77903 .

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Proc. R. Soc. Lond. A. 326, 23-37 (1971) Printed in Great Britain

REVIEW LECTURE

The Snowy Mountains hydroelectric and irrigation scheme (Australia)

BY SIR WILLIAM HUDSON, F.R.S.

(Commissioner for the construction of the Scheme 1948 to 1967) 39 Flanagan Street, Garran A.C.T. 2605, Australia

(Lecture delivered 29 May 1969-MS. received 13 July 1971)

INTRODUCTION: IMPORTANCE TO AUSTRALIA OF THE FULL

DEVELOPMENT OF ITS MEAGRE WATER RESOURCES

Nature has provided Australia with an abundance of mineral and other resources. It was the discovery of gold in the middle of the 19th century which proved to be one of the major factors in the country's early economic development and population growth. More recently mining of iron ore, nickel, lead-zinc, copper, manganese, uranium and other minerals has provided even greater stimulus to the growth of its economic strength. During the last two decades, particularly, explorations have revealed further deposits of rich iron ore and bauxite in vast quantities. During the 1960s hundreds of kilometres of railways have been constructed, some at world record breaking speeds, to bring iron ore from the recently discovered deposits in

virtually uninhabited areas to newly constructed ports on the western coast of the continent for export, mainly to Japan which has established itself as a major market for Australian minerals.

Ten years ago Australia's iron ore reserves were estimated at 368 million tons.t

Today they are believed to be over 20 000 million tons. Bauxite reserves are estimated at 3750 million tons. (Note: More recent investigations have shown these

quantities to be conservative; see Australian Year Books, nos. 53-56, I967-I970.) Speaking of the haematite ore-bodies in the Hammersley Range, only one of the

several such deposits in Western Australia, the late Mr Tom Price, Vice-President of the Kaiser Corporation, said: 'There are untold millions of tons of iron ore in the Pilbara deposits. I think this is one of the most massive ore-bodies in the world. There are mountains of ore there. It is just staggering. It is like trying to calculate how much air there is.' (See Raggatt 1968.)

Despite these examples of good fortune Nature has been far from generous to Australia in respect of the most important of all natural resources, namely water. It is the driest of all continents. Its average annual rainfall is less than 46 cm (18 in), compared with an average of approximately 74 cm (29 in) for North America and

t 1 ton 1016 kg (1 short ton U.S. 907 kg). [ 23 ]



Sir William Hudson

66 cm (26 in) over the total land areas of the world. One-third or thereabouts of the mainland has a desert of 0-25 cm (0-10 in) per annum, and another one-third

experiences semi-desert conditions with an average rainfall of 25-50 cm (10-20 in). One-third of the continent's total area makes no contribution to stream flows. The Australian Water Resources Council estimates the total mean annual discharge from all Australian rivers as some 340 km3 per annum. (Australian Water Resources Council I963.) This is equivalent to a depth of less than 4.5 cm (1- in) spread evenly over the whole of the continent and amounts to approximately 60 % of the flow of the Mississippi, less than 70 % of the Mekong in South-eastern Asia and only 22 % in excess of the Danube. The situation is worsened considerably by the very high evaporation rates. Whereas evaporation and transpiration account for some 50 % of precipitation in Canada and some 70 % in the case of the United States of America

they absorb 90 % of Australia's rainfall.

fII <125

I::71 125-250

~ 2 o250-500

500-1000

I- >1000

As can be expected, these climatic conditions account for the great variability of the flows of most of the mainland's rivers. As an example, the minimum annual flow of one of Australia's major rivers, the Darling, is less than one part in 11000 of its maximum annual flow.

There are two main reasons for the paucity of reliable supplies of fresh water in Australia. One is the absence of any high mountain ranges, the elevation of the

highest peak on the continent being only 2230 m (7310ft). The second reason is the continent's geographical position, the greater part of its northern half being too far to the south to receive regularly the monsoonal downpours of the tropics and most of its southern half being too far to the north to benefit fully from the regular rain- falls of the Temperate Zone. These conditions emphasize the national importance

24



Review lecture

of the greatest attention being given to water conservation, in fact it is believed that

failing the successful development on a grand scale of economic methods for the desalination of water, the shortage of fresh water is likely to be a limiting factor in the ultimate growth of the country.

There is yet another good reason for the conservation and utilization of Australia's water resources on the most efficient and effective lines. It is one which becomes

increasingly apparent every year. Australians are the owners of one of the world's six continents, yet their country supports within its shores only some twelve and a half million people, less than one half of one per cent of the world's population. It has as its neighbours hundreds of millions of people, large numbers of whom are under-nourished and many are living in a state of semi-starvation. Moreover, the world's population is expected to double in the next 30 years or so. This presents a

potentially unstable situation, but apart from that, on moral grounds, to justify ownership of a continent by a handful of people it behoves Australians to recognize, as Sir Robert Menzies, one of their greatest Prime Ministers, has said: 'Australia has ab responsibility, not just a narrow one to feed itself, but a responsibility to play her

part in feeding other persons. This is an International obligation.' Such thoughts as these provide background to the construction of the Snowy

Power and Irrigation Scheme, one of the largest engineering undertakings of its kind in the world.

THE SNOWY SCHEME

The Snowy Scheme covers some 5000km2 (2000 mi2) of mountainous country. It involves the construction of 16 large dams and many small ones, nearly 160 km of

tunnelling in hard rock, 7 power stations some of which are deep underground, and

nearly 130 km of aqueducts to pick up the streams at high elevations and lead them to the various storages and tunnels, providing to all intents and purposes 100 % regulation over the catchment. Its purpose is to supply large quantities of peak load

power for the Australian Capital Territory and the States of New South Wales and Victoria. More importantly, it also supplies large quantities of water for intensive

irrigation production. Although in some respects the Scheme is an unusually complex one, the concept

on which it is based is simple. The Snowy Mountains, located in the southeastern

corner of the continent, are Australia's highest land mass. They are snow covered for five or six months of the year, rendering them the most reliable water collecting area on the mainland. Two important river systems rise in the mountains. On the

inland side of the Great Dividing Range the Murray and Murrumbidgee Rivers flow westward across thousands of square kilometres of dry but fertile alluvial plains before entering the waters of the Southern Ocean near Adelaide in South Australia. On these potentially rich inland plains irrigation is already a thriving and nationally

important industry, but further expansion on any large scale is not possible without

augmenting the flows of the Murray and Murrumbidgee. Rising on the eastern or coastal slopes of the mountains is the Snowy River, which

25



26 Sir William Hudson

hitherto has flowed to waste across the well-watered coastal strip into the nearby Tasman Sea.

Simply stated, the Scheme is designed to trap the unused waters of the Snowy River and its tributaries before they leave the mountains and to divert them through an extensive system of trans-mountain tunnels to the inland flowing Murray and

Murrumbidgee, to augment agricultural and pastoral production. The affect of these

TABLE 1

POWER STATIONS AND PUMPING STATIONS

installed rated head average station flow capacity -"

station MW ft m ft3/s m3/s

Tumut 3 1500 495 151 1776 50.3

Murray 1 950 1510 461 1354 38.3

Murray 2 550 867 264 1390 39.3 Tumut 1 320 960 293 1377 39.0 Tumut 2 280 860 262 1438 40.7

Blowering 80 284 87 1963 55.6

Guthega 60 810 247 292 8.3

PUMPING STATIONS

rated capacity total pumping head

ft3/s m3/s ft m

Jindabyne 900 25.5 760 232 Tumut 3 10500 297 509 155

DAMS

height above total foundation crest length total volume reservoir capacity

name typet ft m ft m 103 yd3 103m3 acre-feet 106m3

Tumut 3 R 530 162 2300 702 18500 14144 747000 921 Eucumbene ER 381 116 1900 580 8800 6728 3890000 4772

Blowering R 368 112 2650 808 11200 8563 1320000 1628 Geehi R 300 92 870 265 1830 1399 17100 21 Tumut Pond CA 283 86 713 217 185 141 42800 53

Jindabyne R 235 72 1100 336 1170 895 558000 688 Tooma ER 220 67 1000 305 1440 1101 23000 28 Island Bend CG 160 49 480 146 79 60 2450 3.02 Tumut 2 CG 152 46 390 119 63 48 2170 2.68

Tantangara CG 148 45 710 217 97 74 206000 254 Jounama R 144 44 1700 519 725 554 35300 44

Murray 2 CA 140 43 430 131 25 19 1900 2.34

Guthega CG 110 34 456 139 57 44 1480 1.83

Happy Jacks CG 95 29 250 76 11.7 9 220 0.27

Deep Creek CG 70 21 180 55 5.33 4 9 0.01 Khancoban ER 60 18 3500 1068 823 629 21600 27

t Type: R, rockfill (at least 50 % rock); ER, earth and rockfill; CG, concrete gravity; CA, concrete arch.



Review lecture

diversions, together with the regulation provided by the various reservoirs, is to supply some 2.5 km3 of water per annum to the inland flowing rivers, sufficient to bring into intensive production about 2600 km2 (1000 mi2) of dry country. In traver- sing the trans-mountain tunnel and pipeline systems, the water falls some 915 m

(3000 ft), thereby generating about 3.75 million kilowatts of much needed peak load

power for the Australian Capital Territory and the States of New South Wales and Victoria.

SNOWY-TUMUT DEVELOPMENT

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a, tributary of theme Murray, ist be divertibed in two parts, namely the Snowyoma-Tumut

I)evelopment and the Snowy-Murray Development. Storage and regulation for each

of these two sections is provided by Lake Eucumbene, with an active capacity of

4.32 km3. The Snowy-Tumut Development provides for the diversion of the Snowy's main

tributary, the Eucumbene River on the eastern or coastal side of the Divide, through the 22.4 km (13.9 mi) Eucumbene-Tumut Tunnel to the upper reaches of the Tumut

River, a tributary of the Murrumbidgee, on the western or inland side of the Divide.

To produce more electricity and also to achieve the desired division of irrigation water between the Murray and Murrumbidgee Valleys, the Upper Tooma River, a tributary of the Murray, is diverted through the 14| km (9 mi) Tooma-Tumut

Tunnel to the Tumut River and thence to the Murrumbidgee. A further increase in

electricity production is obtained by diverting the Upper Murrumbidgee River

27



28 Sir William Hudson

through the 16.6km (10.3 mi) Murrumbidgee-Eucumbene Tunnel to the Scheme's main storage reservoir, Lake Eucumbene, and thence through the previously mentioned Eucumbene-Tumut Tunnel to the Upper Tumut River. The principal power stations on the Snowy-Tumut Section of the Scheme are Tumut 1, Tumut 2, Tumut 3 and Blowering, with a total capacity of 2.1 million kilowatts. Tumut 1 Station is 366 m ( 1200 ft) underground and Tumut 2 Station 244 m (800 ft) underground.Water discharged through this series of power stations is caught and stored in Blowering Reservoir, for release during the summer irrigation season.

SNOWY-MURRAY DEVELOPMENT

2 X2 ? 5,

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Special mentio might be made of the Tum 3 Projec, which accots for

high Tumut 3 Dam is the largest dam on the Scheme. Part of the water passed

hrough t,he turbines is caught in a small reservoir immediately downstream of the power station and pumped up to the main reservoir for re-use during subsequent peak load periods. Pumping takes place late at night or early in the morning when there are ample supplies of cheap surplus power available from the New South Wales

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thr r m espleso ha surpus owe avilbl frmteNw ot ae



Review lecture

thermal stations. This increases the station's load factor from about 3.4 % to about 14 %.

Another interesting feature of the Snowy-Tumut Development is the two-way trans-mountain tunnel which, as already mentioned, connects the Scheme's main storage, Lake Eucumbene, on the eastern or coastal side of the Divide with the Tumut Pond Reservoir, the balancing reservoir on the Upper Tumut River on the western side of the Divide. Normally this tunnel carries water under the mountains from Lake Eucumbene to the Tumut River as part of the inland diversion process; but during periods of high flow in the Tumut and Tooma Rivers surplus water is diverted through the tunnel in the reverse direction, back to storage in Lake Eucumbene.

The Snowy-Murray Development provides for the diversion of the Snowy River on the eastern or coastal side of the Divide through the 14.7 km (9.1 mi) Snowy-Geehi Transmountain Tunnel to the Geehi River, a tributary of the inland flowing Murray; also for a subsidiary diversion by pumping through a 9.8 km (6.1 mi) tunnel from a reservoir on the Snowy at Jindabyne, constructed further down the river from its point of diversion. The major power stations on the Snowy-Murray Diversion are Murray 1 and Murray 2, with a total capacity of 1- million kilowatts.

Normally the Snowy-Geehi Tunnel carries water from the Snowy River to the Murray River, i.e. from east to west. However, during periods of high river flow surplus water in the Geehi River is diverted in the opposite direction, i.e. from west to east, for storage in Jindabyne Reservoir.

Economics of the Scheme

Capital requirements for the construction of the Scheme have been met by loans from the Commonwealth Government, interest being at the Commonwealth Govern- ment long-term bond rates. Repayment of capital is spread over a period of 70 years. These charges, together with all operation and maintenance costs, must be met by revenue from the sale of power. Costs attributable to the supply of water for

irrigation, which are substantial, are provided from revenue from power sales as water for irrigation must be supplied to the States without charge. This illogical financial arrangement of requiring power sales to finance irrigation costs resulted from bargaining by the Governments concerned, despite the greater national value of the irrigation component of the Scheme than the power component.

Under the agreement between the Commonwealth and States, the Scheme is

required to supply peak load power at actual cost including, as already mentioned, the cost of supplying water for irrigation without the recoupment of any revenue from water sales. Furthermore, the cost must not exceed that which the two States would incur if they themselves constructed modern, efficient, thermal stations on the coalfields to supply similar quantities of peak load power. These financial

requirements, difficult as they are bearing in mind that power charges must carry irrigation costs, are being met successfully. This is due in no small measure to the fact that the estimate for the Scheme (A $800 million) prepared in 1954 still holds

29



Sir William Hudson

today, despite the rise in cost of 75 % which has occurred during the subsequent fifteen year construction period. As expected in the case of hydroelectric installations

generally, with the passage of time further improvement in the cost of the Scheme's

electricity relative to the cost of thermal power will undoubtedly occur.

Progress A feature of the construction of the Scheme has been the rate of progress achieved,

the completion date being some 3 to 5 years earlier than originally anticipated. All the many major contracts placed since 1950 have been finished at least on time and many of them well ahead of schedule. For instance, the 116m (381 ft) high Eucumbene Dam was finished one year ahead of schedule.

It was in rock tunnelling that the most spectacular rates of progress were achieved. When the Scheme commenced the world's record speed for driving large diameter tunnels in hard rock, held by California, U.S.A., was lll m (365ft) per week of six days. The maximum driving speed reached on the Snowy Scheme was 179 m (587 ft), an improvement on the earlier world's record of over 60 %. However, it is the average rate of tunnelling that is of more significance. In that respect, the

Snowy's average driving speed for the larger diameter tunnels driven during the whole of 1963 was 17 m (55 ft) per day. This almost equalled the daily rate achieved earlier by California during its record breaking week.

TABLE 2. TUNNELS

excavated lined length diameter diameter

.. , , ------~ percentage tunnel mi km ft & in m ft & in m lined

Eucumbene-Snowy 15.2 24.5 22 0 6.71 20 0 6.10 19.7 Eucumbene-Tumut 13.9 22.4 24 0 7.32 21 0 6.41 28.3 Murrumbidgee-Eucumbene 10.3 16.6 11 10 3.61 10 2 3.10 17.7 Snowy-Geehi 9.1 14.6 22 0 6.71 20 0 6.10 13.3 Tooma-Tumut 9.0 14.5 13 5 4.09 11 3 3.43 20.6 Murray I Pressure 7.5 12.1 24 9 7.59 22 9 6.93 100 Tumut 2 Pressure and 7.0 11.3 23 0 7.01 21 0 6.40 100 Tailwater

Jindabyne-Island Bend 6.1 9.8 14 0 4.27 12 4 3.76 10.6 Guthega 2.9 4.7 19 3 5.87 17 3 5.26 11.6 Murray 2 Pressure 1.6 2.6 26 6 8.08 24 6 7.47 100 Tumut I Pressure 1.5 2.4 24 0 7.32 21 0 6.40 100 Tumut 1 Tailwater 0.8 1.3 29 0 8.84 26 0 6.92 54.5

Of the many factors contributed to the high rate of tunnelling two deserve special mention. These are the use of the 'sliding tunnel floor' and 'rock bolting'. The former comprised a sectionalized structural steel working floor platform some 136 m

(446ft) long by 4m (13 ft) wide, carrying rail tracks, points and crossings, drilling gantry tracks and other tunnelling equipment. A hydraulic jacking system moves each of the three floor units forward in six stages.

The rock bolting technique used in Snowy tunnels, largely developed by Snowy

30



Review lecture

Mountains Engineers, eliminated in many situations the use of steel or timber tunnel supports. The process provides for the use of long tension bolts so placed as to compress the rock around the tunnel for thicknesses in the order of 3 m (10ft). In other words, broken or jointed rock surrounding the tunnel was converted into a

self-supporting arch structure. One advantage of this process was to permit rock bolting to proceed simultaneously with tunnel face drilling, avoiding the installation of steel or timber supports, which inevitably disrupt other routine tunnelling operations.

PROVISION OF SCIENTIFIC SERVICES FOR ASSISTING THE

INVESTIGATION, DESIGN AND CONSTRUCTION PERSONNEL

A complete set of scientific and engineering laboratories, the largest of their type in the country, was established at the Scheme's headquarters. In addition to providing solutions to many scientific and engineering problems, indirect benefits arose from these services in several ways, including the establishment of much closer cooperation between the scientists on the one hand and the investigating, designing and construction engineers on the other hand, to the mutual advantage of both groups. This cooperation between the scientists and the engineers on virtually a day to day basis was regarded as being of considerable importance. While Governmental and University research organizations were approached to give assistance on many occasions, these alone could by no means fulfil the needs of the Snowy Mountains Authority, principally because they were unable generally to meet the priorities imposed by the tight schedule of the works programme and because of their inability in most cases to appreciate fully the complexity and ultimate objectives of the Authority's works. This was partly evident in the field of geology and physics where University Graduates majoring in the subjects had to receive field training for two or three years in the Snowy Mountains Area. A similar situation arose in respect of biologists, who, even with experience in soil conservation elsewhere, required a suitable period of orientation before they became effective on major engineering works in remote and rugged country.

A few typical problems undertaken successfully by the Scientific Services Section of the organization illustrate how the Authority's aims were achieved.

Underground works, a particular feature of the Scheme, have always been associated with unknown and unforeseeable factors. To minimize these, techniques were developed whereby the in situ components of strain and elastic moduli in rock masses were measured, mostly by engineering physicists, concurrently with geological investigations. At the same time photo-elastic and other methods were developed in which appropriately loaded models were used to determine the stress patterns in the rock resulting from excavations. Forecasts made in this way resulted in changes in location and/or in design of underground power stations. The stresses predetermined by these methods were shown to be in close agreement with those measured during and after construction. This knowledge undoubtedly led to the

31



Sir William Hudson

elimination of rock falls and the completion of major underground works ahead of schedule.

The same photo-elastic facilities also played an important part in the rock bolting developments mentioned earlier in this lecture.

In the case of the Tumut 1 Power Station, completed over 10 years ago and where laboratory studies were first used extensively, an estimated saving in the order of A $1 million was achieved as the result of these scientific studies.

In other ways, too, the pooling of the laboratory resources and the progressive ideas of experienced construction engineers, with each group of personnel working together on a day to day basis, were also important contributing factors in improving progress rates and reducing costs. During the period from 1954 to 1966, the average unit cost of tunnelling on the Scheme was virtually static, whereas wages increased markedly.

Many hydraulic problems encountered during construction of the Scheme called for close study and ad hoc research. In a number of cases problems of the control of air entrainment arose, about which little information could be obtained from available technical literature. At four points on the 14 km Tooma-Tumut Tunnel water was admitted down vertical drop shafts to a maximum depth of 131 m

(428 ft). To prevent damage to the hydraulic gates and other structures in the system during operation, it was imperative to reduce access of air into the tunnel to a minimum. Detailed investigations involving analysis and model studies in which kerosene was used to represent air in many cases, led to the development of a fixed system comprising siphons at the top of each shaft and a vortex chamber at the bottom fed at two diametrically opposite points from an annular manifold con- nected to the outlet legs of the siphon pipes. The introduction of these special design features resulted in 99 % of air being removed over a wide range of water flows. Compared with the use of conventional gate systems, this arrangement requires no operation and negligible maintenance. It showed an overall saving in first cost of the order of A $600 000. Experiments on the prototypes which have now functioned for ten years have shown excellent agreement with the forecasts based on the laboratory investigations.

Other air entrainment studies related to the 77.6MW (104000hp) Jindabyne pumping station and the 560 MW (750 000 hp) Tumut 3 pump storage station. Under some operating conditions at low water levels the formation of vortices could become troublesome. A review of literature demonstrated that little was known about the formation of vortices for such large installations, Tumut 3 pumps, for instance, being the largest in the world, nor was enough known about the scaling laws relating prototypes to models. A fortunate circumstance existed in the 16.6 km Murrumbidgee- Eucumbene tunnel, which conveys water from the Tantangara storage north of Lake Eucumbene. The flow in the tunnel can be controlled so that either channel or closed conduit conditions can be achieved; and the water level in the storage varies over a wide range. Systematic experiments were carried out to provide data concerning the formation of free vortices, and at the same time studies were made

32



on a family of homologous models. In this way scale effects were determined and applied to the data collected from models of the pumping plant. Recently the behaviour of the intake of the Jindabyne Pumping Station was checked and found to be in agreement with the forecasts.

The effects of frost action in the Snowy Mountains are severe. In some areas up to 180 frosts in one year have been recorded. This has not only contributed to the marked geological weathering of the granite, but has also accentuated soil erosion on all bare surfaces and presented major problems in the design of concrete mixes. Investigations carried out in the laboratories resulted in marked improvements in concrete durability. Test specimens were subjected to temperature cycles from - 12 ?C to 21 ?C every three hours. Acceptable concretes used elsewhere in Australia either disintegrated or lost 25 % of their original weight after less than 400 cycles, whereas concretes used in the later Snowy Mountains projects normally withstood 7000 or more cycles.

The large Murray 1 power station presented a major development problem relating to the design, manufacture and erection of the three large steel pipelines having a maximum diameter of 4.2 m (13ft 9in) and each being 1830m (6000ft) long. They supply water under a normal design head of 580m (1900ft) to ten 106MW

(142 000 hp) Francis type turbines. The head is extremely high for this type of turbine. It was decided in the interests of economy and practicability to use a special notch-tough steel. Cooperation with the Australian Iron & Steel Pty Ltd led to the development of two steels having notch-toughness at low temperatures superior to that possessed by any of the available steels of overseas origin. In addition, the Authority developed special welding procedures concurrently with quality control -methods including routine radiographic and ultrasonic testing. The finally selected normalized manganese silicon steel proved satisfactory in all respects.

In the early years of the Scheme there was an acute shortage of Australian

engineers, scientists and other key personnel. To meet the situation at least half of the professional men and two-thirds of the other personnel were recruited overseas. Standards of training were variable and experience often was incompatible with

requirements. To overcome these disabilities it was necessary to establish in-training schemes on full time and part time bases according to conditions prevailing at the time. Courses were provided to cover all professional and technical levels. About 4000 men attended these courses between 1955 and 1968. In this way the Authority ensured that its professional and technical personnel acquired high and homogeneous standards of proficiency.

SOIL CONSERVATION

Climatic conditions in the Snowy Mountains Area, particularly above 1830m

(6000 ft) elevation where precipitation and wind velocities are higher than in other areas in Australia, and frost action is most severe, considerably increased the danger of extensive soil erosion developing from the construction of the Snowy Scheme. For that reason special attention was paid in the design and construction of the

Vol. 326. A.

Review lecture 33



Sir William Hudson

works to measures which would, as far as practicable, avoid the creation of soil erosion hazards. In addition, conservation teams were trained and employed continuously on re-vegetating disturbed areas and on applying remedial measures where erosion hazards existed.

The process generally followed in re-vegetating disturbed areas was to plant fast growing exotic trees, shrubs and grasses which hold the surface temporarily while native species gradually take over. In some situations at highest elevations it was necessary after sowing to protect surfaces with a straw and bitumen insulating blanket until the seedlings became established. The aim of this blanket was to hold the soil and seed in place as well as to prevent the formation of needle ice and provide some protection against desiccation.

A total of over half a million trees and shrubs, reared in local nurseries, was established by the Snowy Mountains Authority in and around disturbed areas; also some hundreds of tons of grass and clover seed.

CONSTITUTIONAL AND INDUSTRIAL PROBLEMS

Under the Australian Constitution the rights to generate electricity and to supply water for irrigation are allotted to the six States. As a rule any encroachment into these fields by the Commonwealth Government is strongly resisted by the States. However, in the case of the Snowy Scheme the States of New South Wales and Victoria realized that this project was too large and too costly for them to undertake and also recognized the benefits they would undoubtedly derive from it. Hence their agreement to cooperate with the Commonwealth Government in the Scheme's early investigations. Nevertheless, when the Snowy Mountains Hydro-Electric Act was passed by the Commonwealth Government no formal and binding agreement had been entered into by the States.

During the passage of the Act through Federal Parliament, and later to an even greater extent its validity was challenged, as a consequence of which the Authority was not recognized under law as being an authorized public organization. This uncomfortable situation continued during the first five years of the construction of the Scheme before the States passing supporting legislation. It also placed the States in an excellent bargaining position during the early negotiations on the price to be paid for Snowy power and for irrigation water. (This situation is referred to in the portion of this lecture dealing with the economics of the Scheme.)

During the very difficult period mentioned the Snowy Mountains Authority had access neither to the legal nor industrial courts. It could be sued but it could not sue. Not being recognized as a legal body, it could not acquire land compulsorily, nor did it have access to the industrial courts which as a rule play such a prominent part in Australian industrial relations. Under these circumstances it appeared that the Scheme could encounter endless and perhaps insuperable difficulties from land- owners and particularly from labour unions. On the contrary, ways and means were found to overcome these difficulties satisfactorily. The special arrangements tem-

34



Review lecture

porarily enforced on the Authority for the purchase of land were continued after the enactment of State legislation permitting the Authority to acquire land compulsorily, so were the industrial arrangements agreed mutually between the Authority and the Unions before the legal recognition of the Snowy Mountains Authority by the Arbitration Courts.

With regard to the latter, the high standard of industrial relations built up during construction has been a feature of the Scheme, minor labour troubles only having occurred, and at very infrequent intervals. This favourable situation is exemplified by the level of tender prices received for major contracts. In that connexion, during the early days of construction the Authority was alarmed at the tender prices received from overseas firms, the main contributing factor undoubtedly being fear of Australian labour. However, there was a marked change in the situation after the successful completion of the early contracts, some of them well ahead of schedule. Tenderers had realized that suspicions on the unreliability and inefficiency of Australian labour in the Snowy Mountains Area were unfounded. Many of the acceptable tenders received later were below or well below the Authority's estimates.

Personnel

When the Snowy Mountains Authority was created in 1949 its first task was the establishment of a staff of professional, technical and administrative personnel, and a large labour force. This occurred at a time of acute shortage in Australia, not only of professional and technical people but also of skilled and unskilled labour, causing the Authority to undertake an active recruitment programme overseas, mainly in Great Britain and Europe. In addition, full advantage was taken of the Common- wealth Government's immigration scheme. The result of these measures was that the Snowy Mountains Authority became a truly cosmopolitan organization, virtually a, miniature League of Nations, with men and women from over 30 different countries comprising over two-thirds of the Scheme's population.

Although the greatest care was taken in the selection of these new employees and their families, assimilation of some thousands of men and women, many of whom could not speak our language, into the local community created many problems. These people found themselves living in a remote area in a strange land, in what might at first have appeared to them to be an inhospitable place, parts of it under snow for five or six months per year. Apart from practical measures such as the establishment of schools, the organization of language classes and the like, none of which caused difficulties, the Authority undertook what it believed to be an essential exercise for the successful execution of the Scheme, namely the integration of these strangers from many nations in a happy and contented community. It believes it succeeded in this. At the same time it is only right to acknowledge that Australia is richer for having acquired from overseas these fine new citizens and their many skills.

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Sir William Hudson

Safety

High speed tunnelling, probably the most hazardous of all construction operations, constituted a large part of the Scheme's construction activities.

During the first half of the construction period safety measures normally regarded as adequate were adopted throughout the Scheme and, as might be expected, accident rates were normal for the type of work then being carried out, direct and indirect costs attributable to accidents being a little over 2 % of the total cost of the work. The fact remained, however, that 35 men lost their lives in driving 76 miles of tunnel and many times that number were maimed or otherwise seriously injured. The Snowy Mountains Authority, therefore, in conjunction with its major contractors, decided to embark on an intensive safety campaign and to continue this throughout the remainder of the construction period. A voluntary, cooperative association comprising the Authority and all major contractors, known as the

Snowy Mountains Joint Safety Council, was set up, pooling all safety resources. Direct personal participation by the head of each organization was fundamental in the arrangements for the operation of the Council, enabling' on-the-spot' decisions to be reached for immediate implementation without reference to higher authority. The cost of the Council's activities, which were by no means small, were shared between member organizations in proportion to the number of their employees. Gratifying results were achieved, the accident frequency rate for all employees, the Authority's and the various major contractors', fell by some 70 % and have since been maintained at the lower levels.

A similar measure was the establishment on the works by theb Joint Safety Council of a resident rehabilitation centre, the objective of which was to expedite the recovery and return to work of accident cases. The centre was operated by two ex-British Army remedial gymnasts under the supervision of a panel of two medical officers. In addition to remedial exercises it provided facilities for therapeutic and diversionary occupations. It is estimated that on the average the time absorbed by accident cases from discharge from hospital to return to normal duties was reduced by approximately 50 %.

Units of the Scheme have been brought into operation step by step as each project was finished. Despite the fact that the Snowy Mountains Area has recently passed through one of the'worst droughts ever experienced since the white man came to Australia, the Scheme fully met its contractual obligations for the supply of power and water without rationing, in fact additional water over and above that stipulated for normal supply to the irrigation areas was released during that critical period.

As already pointed out, Australia's water resources are meagre. Nevertheless their potential for bringing large tracts of arid but otherwise fertile country into intensive production has so far been little more than scratched. For the future security of this young Nation it must expand; it must produce more food; it must

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Review lecture 37

carry a more adequate share of the people of the world. Paramount in its development is the full use of its water resources.

REFERENCES

Australian Government Australian Year Books I967-70. Raggatt, H. G. i968 Mountains of ore. Mining and minerals in Australia. Review of Australia's water resources I963 Australian Water Resources Council.



Review Lecture: The Snowy Mountains Hydroelectric and Irrigation Scheme (Australia)

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Transcript of Review Lecture: The Snowy Mountains Hydroelectric and Irrigation Scheme (Australia)