No. 4167 September I0, 1949 NATURE 423 THE SNOWY RIVER PROJECT (S.E. AUSTRALIA) By PROF. s. E. WADHAf1 d PROF. D. M. MYERS University of Melbourne an University of Sydney RRIGATION in Australia, which began in the change of flow in the upper reaches for generation of I 'seventies and staggered uneasily for half a electricity under the most favourable conditions. century, during which it learned its lessons and found The Murray and Murrumbidgee themselves do not the appropriate techniques, has come into its own in fall rapidly enough for this purpose ; but the Tumut, the last two decades. Its extension is regarded as an Tooma (a tributary of the Murray) and part of the essential feature in national development. Most Snowy have sufficient gradient to provide satisfactory parts of the continent lack permanent streams; but conditions for power generation. among the ranges which run parallel to the eastern There are several possible alternatives, and the coastline are several areas high enough and wide final decision was reached after considering thE" enough to form catchments yielding large volumes relative importance of distribution of waters for of water. Some are snow-clad for several months, irrigation, magnitude of power production, and the and thus have a run-off which tends to have a better overall economics of both. The decision involves distribution than others. Among these, the· plexus primarily the diversion of a large proportion of the of ranges and tablelands in the Mt. Kosciusko region Snowy waters indirectly to the Murrumbidgee. It of the south-east is the outstanding example. This has yet to be decided, after more detailed investi­ area contains the Murray catchment and those of its gation, whether the remainder should be diverted to tributaries, the Murrumbidgee and the Tumut, and the Murray or the Murrumbidgee. of the Snowy. The Murray has a system of storages The details of the proposals may be examined in and locks developed during the last forty years, while relation to the map of the area shown in Fig. l. The the Murrumbidgee has the Burrinjuck storage and main areas chosen for power production are: (a) the several locks. The Hume reservoir on the Murray upper reaches of the Snowy; (b) the Tumut valley; holds 1,250,000 acre feet, and will be extended to and (c) the area between the Snowy and the Murray. hold 2,000,000 acre feet. Burrinjuck holds 662,000 The flow of the Tumut River will be supplemented acre feet for irrigation. The Snowy, with an average by the headwaters of the Tooma and of the Eucum­ yearly flow on the tableland of 970,000 acre feet, bene branch of the Snowy, and lower down by waters remains as the largest stream in the region available of the upper Murrumbidgee. In the agreed part of for future development. It rises under Mt. Kosciusko, the scheme the diversion from the Snowy to the and after flowing north, turns southward and falls Murray will be increased by a total amount equal to rapidly near the border of New South Wales and that lost by the Snowy. The remaining waters of Victoria to reach the ocean near Orbost. Its lower the Snowy will be diverted either to the Murrum­ reaches have a considerable system of alluvial .flats bidgee at Billilingera (the Snowy-Murrumbidgee­ which do not need irrigation, but the country sur­ Murray-Tumut scheme), or to the Murray by the rounding them is too poor and too uneven to be same route as the replacement diversion (the Snowy­ worthy of intensive development. From the agricul­ Murray-Tumut scheme). Power generation in the tural point of view it is therefore preferable that the Tumut system will be supplemented by the Yarrango­ water should be diverted across the ranges towards billy River, and in the Snowy-Murray system by the dry inland. t-he Geehi River and Bogong Creek. The use of water for power generation was neglected A flow diagram (Fig. 2) shows the effect of the in the earlier days; but with increasing industrial­ diversions on the major rivers, for the Snowy- ization the need for this development became clear. Tasmania showed the way with its extensive system developed during the 'twenties. The difficulty of using water both for irrigation and electric generation lies in the seasonal nature of the requirement for the former, which is in contrast to the continuous use desirable in electric power systems. Clearly, it is + almost essential that a dual-purpose project should be linked to a grid system of distribution. Such systems are evolving in parts of New South ·wales and Victoria. Many schemes have been put forward for the utilization of the Snowy waters. It became clear that, as two States and the Commonwealth were involved, no action could be taken without either mutual agreement or a most expensive legal argu­ ment. Agreement was reached in February 1949 on the basis of a report* submitted by Commonwealth and St ate officers. The proposals contained in that report are for the interconnexion of the headwaters of the four main river systems (the Murray, Murrumbidgee, Tumut and Snowy systems) with the view of using them to the best advantage for irrigation at the lower reaches of the Murray and Murrumbidgee, but 'with inter- Fig. 1 . Snowy Mountains 'lfea showing sites of major dams • Commonwealth of Australia : Proposals to Divert the Snowy and diversions proposed (canals omitted). Figures are approximate River. Report by Commonwealth and State officers. Nov. 1948. heights in feet above sea· level © 1949 Nature Publishing Group 424 NATURE September I 0, 1949 Vol. 164 require the construction of seven major dams, some <i of them in country which has been hitherto regarded Ft£1 as fairly inaccessible. It is antiqipated that the con­ 01 ·a. ol "' ... struction of the entire project will take some thirty oi ll :';I! > years, but the benefits of the scheme will become li i ;;; "' z 2 .. 0 ot "' progressively available during that time . 01 oi •I oi. .. j .. From the irrigation point of view, the water will '5000 "' iil .. I be used to reinforce and extend the existing areas on " l: H j:'l t!! t? ,.".. II the MUITUIUbidgee and Murray. These areas support very diverse forms of production, from dried fruits, .... citrus and canned fruits, and wine grapes, through - · c _j -,¥)-- .......... g!.I.NO irrigated pastures used for dairying or fat lambs, to « /;) rice and summer forages. In dry seasons considerable 0 •! I I "' It-- c - ..1 -JINI)"I."fNi. volumes are used to help crops of winter forage and .t '"" 1S grain. The allocation of water is through a system i { v.:- I of 'rights' for which the landholder has to pay; "" ..I SILLILING.EAA S...-R ! J, I extra supplies can also be purchased in some years. I I . The right may be the equivalent of one foot of ' Let:• i}JV HOt.• II irrigation water over the whole holding, or may be MultlllUMS.IDGU. R one quarter to one tenth of a foot, depending on the I TLJMU'T R.. Ta Mu.-.R.uM&tOGII. R. nature and situation of the land. The landholder 1000 1'a has to plan his type of production according to the Mu .. llIII.V, R. size of his holding and his water-right, as various crops require various amounts ; rice needs six feet, 0 and winter forages perhaps only six or eight inches Fig. 2. Flow diagram for Snowy-Murray-Tumut scheme. Figures represent average ftow in thousands of acre feet per annum. of water. I Soil problems are frequent in these areas, as the Dams and collection points e ; racelines t ; diversion tunnels -- - -. Power generation : AA, Upper Snowy; BB, Snowy­ experiences of the last half-century have shown. Murray ; 00, Tumut Nowadays it is generally accepted that a more or less intensive soil survey is essential before any 1\'IuiTay-Tumut scheme. In the alternative scheme, iiTigation scheme is planned. Although some soil the annual flow in the Snowy-Murray diversion problems of iiTigated land have not yet been solved, tunnel would be reduced by 410,000 acre feet, a there is sufficient background of scientific knowledge similar amount being diverted from Jindabyne Dam, available to ensure their satisfactory solution. on the Snowy, to Billilingera Dam, on the MUITUIU­ Sociologically, the more intensive the use of water, bidgee. the closer will be the settlement of the land, and the The total average power potential may be determ­ larger the local units of population which can be ined from the average flow at each dam or pond and established. Given effective leadership, such units its height above the point where the river ceases to can be more readily provided with the basic amenities fall rapidly. In the former scheme, the power which have not always been characteristic of rural potential in each of the three generating systems is areas. On the other hand, the forms of produce thus approximately as follows: (a) Upper Snowy: which lead to closest settlement, such as dried, 50,000 kW. (b) Snowy-Murray diversion (Snowy canned and fresh fruits, and wine, are already avail­ R., Geehi R., and Bogong Creek) : 430,000 kW. able far in excess of Australian requirements, while (c) Tumut (Eucumbene, Tooma, Tumut and Yarran­ the future of dairy products is uncertain. It there. gobilly Rivers) : 410,000 kW. The three systems fore seems desirable that the water should be used to have therefore a continuous power potential of stimulate meat production and the growth of forages 890,000 kW. In the alternative scheme, the diversion as reserves against the droughts which periodically of 410,000 acre feet per annum to the Murrumbidgee afflict large areas.