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   WATER supply is third on the Keyline scale of the relative permanence of things agricultural. To nations as well as to farmers water supply is often a conflict and a dilemma.

   In the discussions on climate the reader will have been conscious of the fact that land shape intruded. By the time the first two factors of the Keyline scale, namely climate and land shape, had been dealt with, water supply had already figured prominently. Throughout the discussions on the Keyline scale, the various factors show close interdependence upon one another and that many relationships exist between each and all. It has been clearly shown also that this relationship, so typical of agriculture, points to the need for a more practical approach or some basic guide in these matters which could prove or disprove the validity of such a concept as the Keyline scale of permanence.

   Climate and land shape have their degree of permanence through no effort of man, but water, suitable agricultural water, is not always naturally permanent. It has to be made permanent for successful agriculture, and the supply has to be completely reliable. House water and stock water are naturally permanent in some circumstances, such as from springs and rivers, but under Australian agricultural conditions, in which water is always the critical factor, permanent natural water is seldom adequate or suitably distributed for basic planning.

   "If water is critical none should be wasted" is the Keyline aim and the guide to planning.

   The greatest environmental change that can be made even when there is sufficient rain water for agriculture, occurs in circumstances where there is a lack of long-lasting permanent water supply and when the incidence of rainfall is inadequate or wrongly timed. Where natural supplies are insufficient, dams that have been constructed for irrigation can also provide stock water, and the requirements may be satisfied by as little as one per cent. of the total storage capacity. The location and the design of dams to conserve water are based firstly on climate and land shape. These two factors must always be studied together. Good physical sites for water storage are only suitable if they can be filled. It is the definite aim of our plan to convert what at first appears as an impermanent supply into a secure and permanently conserved supply. The water aims of the plan then are, firstly and in order of preference, to make provision for household and stock water supplies, then to prepare the land surface where necessary so as to get sufficient rain into the soil from each rainfall to promote the increased development of the soil. This procedure, and with other controllable conditions, will cause an improvement in soil climate. Again, all the run-off that comes from ordinary rain must flow into farm irrigation dams. Finally, all the flood rains that can possibly be held and be used profitably later must be diverted into all types of storages whose capacities have been planned to these ends. From my observations there are few areas in agricultural Australia where this cannot be done.

   All high conservation sites where sufficient water can be brought into them by water conservation drains constitute the highest value in water storage. Such dams generally are to be used for irrigation immediately when irrigation would be beneficial. This could be as soon as seven or eight days after rain in the summer months. The next lower sites, there may be fewer of these and they are often larger, are to be held in reserve as "reservoirs" until the irrigation water of other sites is nearly depleted. And finally come the lowest or "lower dams" or series of dams, which generally have the largest storages per dam but which may be fewer in number. These last are usually pumping dams and are used for general irrigation water.

   The picture then is of three types of dams--(1) the high series, which may be true "Keyline dams", in suitable undulating country; (2) intermediate dams, i.e., reservoirs; and (3) lower dams.

   Some or all of these dams will be used for other than irrigation purposes. A suitably placed dam can be used as a house supply or to supply stock water via pipelines and troughs, and sufficient reserves will be held for these purposes. Generally speaking, the more efficient and complete the use of water on a farm the more it becomes necessary to increase the number of stock watering points. With full water control from Keyline planning, the farm environment improves, the soil improves; the pasture, crops and stock improve in health and condition and their numbers may increase many fold with the growing capacity of the property. Increased stock numbers calls for increased watering points and for good management. A property now served by six water points may require, and very profitably employ with better development, thirty watering points. Happily, the supply of such watering points is a very simple matter in the general water conservation planning of Keyline.

   The whole question of the planning for farm water supply needs critical examination. There are recognised Government authorities on farm water conservation who are doing their best to educate farmers on these matters. Soil conservationists also consider water and advise the farmer on how to avoid the menace of soil erosion by water. And there are others, in fact many other sources of agricultural advice provided by Government agencies, but the advisory authorities are often at variance. The approach of the usual water conservation authority influenced by a concentration on his particular branch of the subject and often lacking a suitable background of agricultural knowledge, is on a somewhat different plane to the soil conservationist and the agriculturalist. Generally speaking, the Government soil conservationist may not touch the work of water conservation on the farms and grazing lands except and only insofar as it concerns his work of providing and advising on means designed solely to conserve soil, and so the provision of a small almost useless dam as a "gully block" to stop soil erosion is as far as he may go.

   The water conservation authority in New South Wales who controls and designs dams and who advises farmers on farm water conservation may not have anything to do with soil conservation, and if the dam is likely to silt up, that is not his concern; it belongs with soil conservation. What is the upshot? Do we find the agricultural officer co-ordinating this frustrating division of authority? Indeed no; he is often careful not to mention either soil conservation or water conservation--it has nothing to do with him. But he is wrong. Both soil and water, indeed every agricultural aspect of soil and water, should be his concern. If he is not the prime authority on these basic agricultural matters, then why isn't he so?

   My approach to the subject of water conservation and the use of water on farms does not follow that of the orthodox lines, and by inference, it could be taken that I am critical of such methods. Of course this is so. Many of the orthodox approaches to agricultural education, and particularly those concerning water on the farm, need criticism.

   Now, water conservation and the use of water on farming and grazing land is essentially agricultural. Education on the matter should be controlled agriculturally. But the present water authority, namely the civil engineer, will immediately cry, "What do they know about the matter? This is a job for the engineer!"

   Now, while it is agreed that the engineer comes into the farm water problem, isn't it also apparent that the job of providing the dams has not been done. As recently as last year, 1957, and the latter half of 1956, despite five years of abundant rainfall, drought again showed that we still need all the water which we can collect and store. Thus it is not helping matters very much when officers and administrators connected with agriculture agree with the cry of the engineer. It must be patent, too, that the engineers cannot greatly assist until agriculturalists themselves fully appreciate all that is involved and lay the whole problem before the engineer, who may then be able to advise with practical designs. However, if the work is partly an engineering job and the Government engineers were widely experienced in these very special matters, then of course the engineer should not be wasting his valuable time assisting the few farmers, but should be teaching every officer of agriculture, so that they, in their direct contacts with the farmer, could assist the thousand or ten thousand farmers.

   The belief now that the engineer is the expert on these matters is based on the fact of his training as a civil engineer, which includes a study of earths (sands, clays, rocks, etc.) as structural materials for various works. He can design and build the giant dam, to him a relatively simple matter, since that is part of his education and experience, but his training does not include any particular study or experience nor has he carried out experiments on what must seem to him such an insignificant structure as merely a farm dam. Who can blame the engineer for being unimpressed with the agriculturalist's present conception of the farm dam?

   While I am willing to concede that in the earlier days much attention was given to the big dam as a necessary public work, e.g., Burrinjuck and Hume Dams and their irrigation areas, there was certainly no proper attention given to what would have been the alternative effect if properly located and designed farm irrigation dams had been provided over large areas of eastern Australia.

   Full investigations along these lines would not have cost a great deal of money, but if it had cost ten or twenty million pounds to get the answers it would have been little enough, since by now there would have been no problem of droughts because the effective conservation of the flood-type rains on the farms and grazing lands would have more than counterbalanced the overwhelming cost of drought and the high cost of floods. Furthermore, there could hardly have remained on agricultural land the hazards, still very much with us, of serious outbreaks of fires. Were a comparison of size of the water storages made between big dam schemes and the totality of farm dams, then it is worth saying that the conservation capacity of irrigation water that would be available if 30,000 farms and grazing properties in N.S.W., each one 1000 acres in area, were given the storage capacity they could hold, economically store and use profitably, then the amount of water would exceed that of the conservation capacity of the Snowy Scheme (the Adaminaby Dam alone will hold eight to nine times the water of Sydney Harbour), plus Burrinjuck Dam and plus a few other big dams. If each farm could hold 300 acre feet of irrigation water storage capacity there would be a combined capacity of nine million acre feet. Now, 300 acre feet is not an unreasonable figure for a thousand-acre area. For instance, it is much less than the capacity rate of "Nevallan" and "Yobarnie", and is not any more than the extra water that will be conserved at "Pakby", near Bathurst, when this new property is developed, and is much less than the capacity of one of the new farm irrigation dams so far completed at "Kencarley", our new property near Orange. There are hundreds of millions of acres of agricultural land in Australia that would have some profitable potential water storage capacity when compared with the thirty million acres of the 30,000 N.S.W. farms mentioned only by way of illustration.

   The farm irrigation dam is a worthwhile structure. As part of the agricultural conservation and use of water on the farm, the farm dam is as completely a specialised structure as any of the giant works that the engineer loves so well. To me it is just as important a job as the "big" dam. It could be even more important and it requires proper principles of precise location based on an agricultural appreciation of the factors of land shape and climate. It has correct but specialised design based on the above factors and also on the depth of water, the foundation materials and the earth available for the wall, and on the particular use to be made of the dam. It needs set construction methods, based on all the foregoing and on the type of equipment that will be used in its construction. (See also Chapter XVIII and Pictorial Section )

   The engineer well knows that earths, unlike iron, steel, brick or concrete are not stable structural materials, the behaviour of which can be accurately predicted in all circumstances, as can be done for these other materials he knows so well. There is just no substitute for wide experience (particularly experimental or trial and error experience) and mature judgment in this specialised agricultural field of farm water control. Agricultural knowledge is a first essential. The scaled down model of the "big" dam, which is the civil engineer's usual offering to the agriculturalist as a solution to the problem, is not nearly good enough. There is as much art and achievement in a fine watch as there is in a giant locomotive. The fine watch represents the farm dam, but who would employ the locomotive engineer to design and make the watch? Yet the farm dam situation is analogous. But most of us are little people who love the colossus, the giant, the big job and the mammoth spectacle. We no doubt have an inferiority complex engendered perhaps by the insignificance of our life span against the evidence of great age in the geological forms with which we play. We are appalled by the immensity of the earth to our puny forms, and the insignificant size of the earth in the vast reaches of outer space, and are overawed by the fantastic precision of atomic movements against the clumsy efforts of our own hands. These feelings are related to the engineer's worship of the big job. He feels good if he can, just once, stand in the immensity of his own work. I know this feeling only too well.

   This complex in many of us I may explain the sometimes ridiculous perpetuation of bigness in engineering, as, for example, the big dam for flood control which does not control floods. These big dams never can control floods as effectively and cheaply as the many farm dams. This must soon be so obvious. However, works that are next to useless and costing millions are not the fault of the engineer. They are built because most of us approve, and as taxpayers we all pay for them. It is relatively easy for engineers to stampede on occasions even the wisest administrators into foolishness, if the foolishness is big enough.

   There is, of course, this little complex which demands big things, but surely there is appreciation of the power of the little things, so many of them; for example, the power of catalytic change in the viruses or the forces in neuclei. Power and immense control comes from controlling the little things. Again, water on the rampage in a flood is uncontrollable, yet it is easy to control the smaller quantities of water where it falls as rain before its accumulation gets out of control. The latest flood control structure is Glenbawn Dam, on the Upper Hunter River in New South Wales, and it is now nearing completion. It is a multi-purpose dam. It has three "pools" with imaginary horizons; one is the lower or reserve pool to regulate river flow downstream; two is the middle pool for power, and it is sufficient for the water supply for a thermal (coal) power station but nationally insignificant for water-generated electric power; and three is the top or flood control pool. Although direct irrigation was a prime original purpose for constructing this dam, the cost of water reticulation, pipelines, canals, channels and drains is so high that it is unlikely that this original purpose will ever be followed. Of course, Glenbawn Dam is not a solitary example of this particular problem of reticulation cost. There are other big undertakings, and huge volumes of stored water will become available each year for the next ten years, yet without means being provided for its use for irrigation purposes. The reticulation works to make use of the water, which is more often than not twice the cost of the big dam, is in practically all instances several years behind the water supply.

   Now, Glenbawn is a moderately large dam. The total height of the wall is 251 feet, the maximum depth of water at the wall is to be 245 feet, the width of the wall is 1800 feet at the base, and the length of the wall is 2700 feet; the quantity of earth and rock in the wall is 10,000,000 cubic yards. The total cost of the dam is to be £15,000,000, and the total cost against yardage is thirty shillings per cubic yard. Again, the total water storage capacity of Glenbawn Dam is 293,000 acre feet from a catchment area of 500 square miles, equal to 320,000 acres. The dam will require a total run-off of ten and a half inches from the whole of its catchment to fill it from the empty condition. What is there to be said?

   In the first place, one would have expected some public reaction. But there has been no wide public criticism directed against Glenbawn as a national worthwhile project and no criticism of its cost, or the cost per yard of wall, or the cost of its water storage capacity, which will be about £50 per acre foot. The capacity of Glenbawn's theoretical flood pool in relation to its watershed area makes it a much more efficient flood control dam than many others, and if the whole of its capacity were used for flood control it would surely be a most effective flood control dam as far as retaining water from its own catchment area is concerned. I know of none other that would approach it, though, of course, it is not a big dam as big dams go. The cost problem can be further appraised.

   The cost of Glenbawn Dam represents an expenditure of £47 for each acre of its entire catchment area, or £47,000 for each one thousand acre farm or grazing property or forest area. This money does not improve any of the catchment area, while it renders useless some of the best land in the vicinity by covering it with water. The catchment area has to be improved in other ways with more money if Glenbawn Dam is to be protected from siltation from its deteriorated catchment.

   It is appropriate here to examine the purposes and aims behind Glenbawn as a project and to determine alternatively how far these could be satisfied by an agricultural development approach such as the Keyline Plan. Hence the first requirement of Glenbawn, and a laudable one, is to influence river flow by keeping the flow more constant. Pump irrigation along the river is assisted and the aquifers, beds of water-bearing, sands and gravels which are important sources of ground water and taken from wells for both agriculture and industry, are to be replenished. To the extent that Glenbawn may provide increased water in the river for pump irrigation from the river, it is providing for the costliest type of irrigation to those farmers affected but at the lowest reticulation cost to the Government. However, this requirement of controlling river flow would be much better satisfied as an incidental to land development, as will be seen before the end of this book.

   The second purpose of the Glenbawn scheme is the provision of water supply for a thermal power station. This could not be met as an incidental in land improvement. The sole answer to this special problem is a dam located, designed and constructed for this special purpose. It is unlikely that the site selected for Glenbawn was entirely dictated by the power station water requirement, so a dam much smaller than Glenbawn and probably more suitably located for its special job, could be constructed at a very moderate cost.

   The third purpose, flood control, is, in my opinion, not a logical one. Water should be conserved for use, and especially on the Hunter. But the water of Glenbawn is unlikely to be used for irrigation, other than from its effect on river flow, as the reticulation cost would be too high. The dam conserves roughly one foot of run-off from 300,000 acres; thus it could supply, disregarding evaporation and channel seepage losses, two feet of irrigation water to 150,000 acres at an extra cost of, maybe, twice the dam cost, £30,000,000, making a total capital cost of up to £45,000,000 for 150,000 irrigated acres, or a cost per acre of irrigated land of £300, plus the original value of the land. Glenbawn would lose effectiveness as a flood control dam if used in this manner for irrigation. For these reasons, Glenbawn is apparently not the best place to conserve this water, and at such a cost it may have been better to let the water go through to the ocean, although this water is wanted badly for agricultural uses.

   Unfortunately, however, these direct irrigation costs cannot be verified now, but it is apparent that the whole matter is causing concern. The dam is nearly completed but no major works for the reticulation of the water have started. At the moment an inter-departmental committee of enquiry is investigating all these aspects of Glenbawn, and their findings, if published, should be of assistance in the assessment of the value of this major public work.

   Glenbawn is only a suitable flood control dam if its entire capacity is available for that purpose, i.e., if it is always emptied as soon as possible after a flood fills it. Yet it is a multi-purpose dam and is less effective in flood control according to the volume of water retained in it. It could still be classed as upward of 50% flood control effective, and that, by comparison with others, is very good.

   The large multi-purpose dams for flood control and irrigation have always seemed to me to be a partnership of two completely irreconcilable fellows. The irrigationist wants all the water held. The flood-threatened want the dam kept empty. Very naturally these dams, which are always costly, have an unhappy history.

   The final question is, can the water that would normally cause a damaging flood be conserved agriculturally in such a way that storage capacity would be available to catch the next flood? The answer to this query is in the affirmative when the best water conservation plans are combined with the most effective irrigation methods. And this is the meaning of Keyline.

   The position is reviewed in this way:

   The Keyline approach offers water conservation in different but special-purpose structures designed to conserve and use, but not to waste water or allow water to waste. If it succeeds in this there is no flood problem. In order to compare the different approaches it must be assumed that authority is equal. If one authority can do all the things necessary to build Glenbawn, then another must have equal authority to take the alternative measures necessary in the catchment area of the big dam. However, the catchment area of Glenbawn contains some of the steepest country in the Upper Hunter region, with over 60% of its catchment having slopes exceeding 15 degrees. As the conservation of water by improved agriculture and in farm dams in such a region would be hard to determine, the comparative figures below should be taken as applying to the more general class of country which is typical of our agricultural land. Moreover, we are interested in all the land of the Hunter Valley and not only the relatively small watershed of the Glenbawn Dam.

   Water conservation costs in Glenbawn are £50 per acre foot. The cost of the conservation capacity on the farms in a catchment area of Glenbawn's size would be less than half of this cost, and I judge this on my own experience of many dams constructed to the designs in this book.

   My costs of water conservation capacity on our farms range from £6 to under £50 per acre foot, disregarding purely experimental work. £6 per acre foot is low, but I have seen many sites on other properties where it would be even lower. The full capacity required then could be conserved generally at less than half the cost, and even this half provides or makes provision for an outlet system in all the farm dams and also includes the irrigation drain for the reticulation of the water. Approximately 50% of the water capacity would be flow water not requiring pumping and would be available for irrigation in the lowest cost manner possible. This would be as much or more water than Glenbawn can provide for irrigation. Of the balance which would be pumped, most of the water could be employed also in flow methods of irrigation. These methods are discussed in detail later.

   Not only could there be a comparable capacity provided at less than half the cost, but included also there could be full irrigation provision for at least 50% of the water (more than Glenbawn flood pool) and partial irrigation provision for the remainder. To accomplish this under the present set-up, Glenbawn costs would be more than doubled. Under the alternative agricultural scheme which I advocate, the water is conserved on farms, on grazing land and forest land, in different kinds of dams each with a different and particular purpose. All the higher dams on each farming and grazing property would generally be used for irrigation. Within a week of rain they often could be profitably employed. The main method of irrigation would be by 8- or 10-inch outlets from each dam and distributed by the Keyline flow system. The lowest dams or series of dams on each property would also be used for irrigation as soon as weather conditions dictated. Keyline irrigation is designed to take the maximum advantage from this water in as short a time as possible. The reservoirs or "middle" dams or series of dams would not be used for irrigation at this time. They are reservoirs supplying perhaps stock troughs or holding water in reserve. They would be used for irrigation after the water in the high and the low storages had been used. Whenever heavy run-off rain occurred there always would be storage capacity in at least both the high dams and the low dams. Also, in a planned design of use, no run-off rain water would waste from the land until all dams were again filled.

   There is also another great storage capacity available on the farming and grazing properties of such a five-hundred-square-mile area. A Keyline soil development programme would increase the general capacity of the soil to absorb at least two inches of additional rainfall, thus providing the lowest cost storage of all.

   The money required for the project under this approach would not be spent with little return, but would produce directly a quick and certain return. If advanced to the farmers and graziers it would be repaid quickly and be available for further work. There is big profit to be made from water control in agriculture.

   I have said that Glenbawn compares more than favourably with other flood control dams. It can hold a so much greater proportion of run-off from its own catchment that flood water from its catchment is, comparatively again, not likely to add to flood flow. Now, Glenbawn's catchment is only 500 square miles, a small area 20 by 25 miles, and its effect in controlling or even mitigating a major Hunter River flood is not of any moment. Glenbawn is what is often classed as a "head-water" flood control dam, and such dams drain areas up to one thousand square miles. Nevertheless, many such dams as Glenbawn would be needed to affect a really big Hunter River flood. But if £15,000,000, as spent on Glenbawn, was made available as loan money to the farmers and graziers for the development of their properties in the Hunter Valley, not only would the present shocking waste of water cease, but a lot of other wonderful changes would follow.

   Another interesting cost comparison is that the cost of Glenbawn on a yardage of earth in the wall basis is at least eighteen times greater than my own recent costs of earth moving for farm dams.

   The ratio of earth moved to water storage capacity in Glenbawn is in the order of one cubic yard of earth to forty-two cubic yards of water. The best ratio of any of my farm dams is one cubic yard of earth moved for a capacity of sixteen cubic yards of water. A more usual ratio for farm irrigation dams is one to five or six. The higher the ratio, other things being equal, the lower the water storage cost. So, while Glenbawn's earth-water ratio is perhaps eight times more favourable than many of the farm dams of Keyline, the earth-moving cost is eighteen times higher, and, as is seen, provides a heavy balance in favour of agriculture and for keeping the flood rain where it falls.

   I have no personal interest in and particularly no animosity towards Glenbawn as a project, or towards the men who approved it or those who designed and built it. It is selected here for discussion because it is new, its construction costs are today's costs and are known and real. Glenbawn also presents the facts for this type of dam in a more favourable way (other than its high cost) than any other dam of the type I know or have read about, including those in other countries. I know Glenbawn's background, climate and its conditions. We all recognise the Hunter River flood hazard. Glenbawn Dam constitutes an excellent basis of comparison.

   The Hunter River Flood Hazard.--It is not my purpose to minimise the Hunter River flood hazard. The dreadful loss of life, property and valuable surface soil of which we were witnesses in 1956 and which had a world-wide advertisement, has become such a holocaust that everyone is prompted to think in terms of flood prevention. All that the average citizen has is the scheme propounded by the Water Conservation Commission to build seven large dams, of which Glenbawn is by no means the largest, at the cost of countless millions, to do a job which experience now suggests they will not accomplish. If sufficient of the public think along the lines of seven big dams for the Hunter River district the parliamentarians will follow their lead and eventually build seven large dams. Who is likely to advise against it? Not the engineer. He insists that flood control is a big problem, a task only for the engineer, and who is not impressed and convinced of the size of the problem when watching a river on the rampage in a big flood. The official agriculturalist, then, what has he to say about the matter? Virtually nothing! He, most unfortunately, has been pushed out of the picture altogether, for even when a Government decides to do something to assist farm water conservation, and wherein lie the solution to these problems, the administration of the project is given to someone else. What has the official soil conservationist to tell the people? Only that, in certain instances, four to five and a half inches of heavy rain was held on the land of a farm or a grazing property where soil conservation methods and structures were used, but as the big floods are caused by twice this amount of rain he thinks big flood control dams are necessary. In fairness to those all-too-few soil conservationists who think differently, I must record that some do believe that continuous flood rains up to twelve inches or more in 48 hours can be controlled, conserved, and later used on farming and grazing properties. Some of these men in other countries wage a continuous fight to enlighten public opinion, but they have against them the policy which provides the truly fantastic money allocated to the big works for engineering control.

   Australian floods differ in the amount of rain which causes the destructive flood. Total flood-period rain of twelve inches or less is the cause of most of our floods, but there are some small areas in the north along the easterly coastline where rains up to twenty inches occur over a short period. From my own experience of these matters (in the increased conservation of water in the soil for the development and improvement of soil, and in the location, design, construction and use of many farm irrigation dams), I know that the control of flood rains up to twelve inches is only a matter of water conservation for profit where the lowest cost and the greatest advantage comes from the control of water where it falls, namely, on the farm lands, grazing properties and forest areas. In these instances there is no flood problem but only the matter of preventing the illogical waste of needed water. In those few areas where the floods involve rain of up to 24 inches over a flood-period it is still logical to aim at the economical conservation of the largest amount of water which may be later used profitably on the farms and on the grazing lands before considering any other approach. The last approach of all should be the flood control dams, and then they should be planned only as many smaller dams located in forest areas where the water could be flowed over the forest land. Forests, when managed for the express purpose of disposing of excess water, can constitute the greatest absorption capacity of any type of land, and may also provide profitable use of the surplus water later in the trees themselves as a timber crop.

   Big dams are justified only for purposes that require water for use for community or wide national advantage. Every city and town must, therefore, have an adequate and completely reliable water supply and so must plan storages of a capacity suitable for the projected increased population of future years. The large high mountain storages for electric power generation have been generally a prime factor in the development of many countries, although today other sources of power are often more economical and present technological development may tomorrow make such water-generated power completely uneconomical. Many fine large irrigation dams conserve water which cannot be used where it falls, for instance from snowfields, and these dams enable the establishment of flourishing irrigation districts in country that was virtually desert. Always, though, the bigness of the project is used too much as the most convincing measure of its success. While many large water schemes are justified by real success, the general large-scale irrigation project should always be more critically examined against the cost of the irrigation land which can be produced from the many farm-scale projects. The glowing success stories in words and pictures of some Government irrigation areas are not confirmed in the profit and loss account of the project, since the costs of irrigation are not directly assessed against the irrigated land. The capital costs, if disclosed against each acre of irrigated land, would be found in some instances to be so high that only the toll of tax on all the people of a State allow the schemes to exist at all. However, my quarrel is not with the concept of the big dam as such but with the viewpoint that fails to realise or even consider the comprehensive nature of, and the very wide national effect to be secured from, the many farm dam and irrigation projects.

   At present we are in a position of serious lack of public thought as to what is correct in methods of water conservation. We must get our thinking right first, otherwise we are likely to impose a dreadful legacy in the form of continually wasting lands upon a beggared posterity. Education of public opinion on the basic importance of agricultural land as the foundation of the nation's very existence should begin in the schools.

   The problem of floods becomes social and national as well as scientific and preventative. Following every flood, we need to concentrate our money on repairing damage and our sympathy for the victims of the flood. We read that the flood damage in a certain river valley reached one million pounds recently. (The damage from one Hunter River flood was assessed at £1O,000,000.) Terrible! Of course it is terrible, and it is worse because human lives were lost or jeopardised.

   The real problem, however, is not the £1,000,000 of flood damage but the sheer waste of more millions of pounds worth of water in a country that cannot afford the luxury of wasting any water.

   Why is there not any real effort made to keep all our precious water? Because the job is too big for the nation? Because it requires a colossal amount of work and a hundred millions or more pounds, pounds which we do not have? On the contrary! The real job is not a series of big dams, while these will help, but simply thousands of farm dams which thousands of farmers are capable of making and who could have finished them ere this had our agricultural authorities been determined to retain overall control of matters affecting these wide aspects of water and land development.

   There just must be a new approach to water. Can't we forget about the site for the giant dam on the river for a while and take a look at water where it falls, since it is here our greatest source of wealth originates?

   In the discussions on land shape it has been conclusively shown that practically all land is contained in what I have called "primary land units". These units are the catchment areas of the primary valleys, and most of them flow to secondary valleys. These two types of valleys are the source of all flood water, but they also contain the most practical and economical sites for the storage of the precious water and as well contain in their catchment areas the land suitable for the most profitable use of the water for irrigation. All the problems and answers of water and land are contained in these lesser units of land.

   To get back to the present inadequate advice on agricultural water which is not given by agriculturalists only. Farm water conservation for irrigation on the farm is widely spoken of as supplemental irrigation and sometimes insurance irrigation. Both could be more fittingly described as panic irrigation. The basis of too much of the official advice on supplemental irrigation is the complete conviction that such irrigation on the farm does not generally pay, but that a farmer should have a little irrigation land which he may use to supplement the general rain-only nature of the farm. By having only a small area of irrigation land and managing this efficiently he may then make it pay. In contrast to this and in circumstances where the production per acre from the type of farming is high enough, supplemental irrigation often pays handsomely. In circumstances where it does not pay, then it becomes "insurance irrigation". Like life assurance, there is no real profit in it for the assured, but it is a "good thing". It may save the farm in a drought, and many Australian farmers were glad of their insurance-type irrigation projects in the drought of the latter half of 1956 and all through 1957. It seems that the worst type of water scheme is better than no scheme at all. But what a dismal manner in which to regard such vital matters as water and irrigation. Expert advice says that a farm dam for irrigation should be planned against the minimum annual run-off of its catchment, so that the dam is sure to be filled each year. The water supply is therefore said to be reliable, but at the time of writing there has been no run-off for over eighteen months in nearly all the areas where this advice is given. While this type of advice must be scrapped, it is not quite as ridiculous as it seems. Again, the real trouble goes a little deeper, namely, to the orthodox farm irrigation dam. This structure is built usually in the valleys of the farm first--anywhere--and it frequently has land below it which could be cheaply irrigated were there an outlet. But is has no large outlet to enable water to flow from it and do at least part of its own distribution. Instead, the water has to be pumped up from the dam, and, in most instances, as the water level lowers from use, the pump and engine follows the receding water down into the mud of the dam. Invariably, such water is used for spray irrigation, which is generally the most expensive type of irrigation, both as to initial cost and running expenses. Spray irrigation is one of the methods of irrigation and has its own particular provinces and uses as well as many variations, but the method of irrigation used should always be the one that best fits the circumstances. If the farm irrigation dam is to be the basis for irrigation, then, if any dam is located wrongly or lacks design and is constructed badly without adequate outlet facilities what chances are there of efficient irrigation. Usually, then, one dam and a small supplemental irrigation scheme is all the farmer can tolerate. The rest of his run-off water can waste away, since he cannot afford to collect and conserve it.

   Before all the run-off water can be conserved plans for the economical use of the water are needed.

   The idea that a large farm dam filled in a good season is a failure if it becomes empty by irrigation is not sound. Water has to be used. Just storing water is not economical. There will be reserves of water elsewhere on the farm as described earlier. Water is a means to an end, and when all the water of a particular dam is used to this end, namely, the growing of crops or grasses, the dam is not a failure. The soil on which the water was used will be better; the crops and fodder were produced and both can be conserved, and this is successful use of water. However, a dam or a series of dams remaining full because the water cannot be used profitably is most assuredly plain failure.

   A large farm storage that may fill only once in three years can be a fine investment for the farmer. The land below the water line of such a dam when emptied. for irrigation is not waste land. When properly treated, as I have found, it can be used then for special crops and should be the highest value land on the farm, with the single exception of irrigation paddocks.

   It is so much simpler and more natural to turn a tap to get water than pumping it. So the outlet through the wall and the turn-on valve are features never neglected in the big community dam. Any design for a farm dam that does not include a means to this end of turning on the tap is deficient.

   Further, it should be realised that water storage on farms has many factors much more favourable than those of the "big" dams. Foundations are generally better, earth for walls is better, and hazards from heavy rains during building are negligible, while earth-moving costs are always very much lower.

   There is this also to be said of water supply, the third factor on the Keyline scale. I believe that the overall planning techniques of Keyline provide the best possible methods for the location of farm dams and the best practical relationship between the high, medium and low types of dam. From my experience, I feel confident that the designs of the dams presented in this book will completely satisfy the requirements of the farmer and grazier, and that the construction methods and the various techniques for the use of the water will be so economical and profitable for the farmer that the ultimate aim of not wasting any water can logically be instituted as the best possible investment policy a farmer may make.

   With Keyline planning and design the farmer and grazier will find that he can conserve just about all the water that would now run to waste from his property. He will certainly carry more stock and he will need more watering points and paddocks. If he has not yet, he will soon realise that farming is big business. The capital value of all farms can be increased enormously, and landmen, because of the favourable taxation provisions as they apply to his business, are in a position to finance the development of a very big capital asset returning good dividends and in the most advantageous conditions. And there is probably no country in the world where these conditions are more favourable for him than they are in Australia.

   Water cannot be dismissed with the conclusion of this brief chapter on water supply, which is the third factor on the Keyline scale of permanence. The whole question of the simple and direct factors of storage cost and economical use of irrigation water as between these farm dams and the big dams is capable of a much wider comparison than I have illustrated. The largest and most economical storages in our vast Snowy Mountains Hydro Electric Authority scheme will not provide water for irrigation as cheaply per acre of irrigated land as many of the favourably located farm irrigation dams. Indeed, important as the scheme may be nationally, were it not for the electric power generating capacity involved, the whole Snowy scheme would not be even of secondary importance when compared to the work of providing farm water storage and irrigation as effectively as is envisaged in these pages.

   A comparison of the farm dam and the great Adaminaby Dam of the Snowy Mountains Authority may seem ridiculous on the face of the gigantic size of the one to the minute nature of the other. Yet the number of farm dams that are needed throughout the agricultural lands and the capacity of water which they collectively could hold, would truly, as we have seen, be a huge scheme itself, albeit a scheme composed of innumerable smaller units.

   The bigness and urgency of the full development of the farm dam and irrigation project is not fully realised by merely appreciating that they would have much more water storage capacity than all the big dams and would irrigate much more land extending over all the agricultural areas of the Commonwealth. There are these other important aspects. As always, there is the great question of transport. Water from any big scheme has to be transported great distances, which costs both large sums of money and big water losses in channel seepage and by evaporation, but from the farm dam the transport of the water is necessary for the shortest of distances, often only a few feet and rarely more than 300 feet before it comes into practical use, thus saving enormously on reticulation costs and water losses. Again, the question of transport becomes a powerful cost factor in the construction of these two types of dams, the big storage and the farm irrigation dam. Earth for the construction of farm dams usually is moved a distance of from a few feet to 200 feet, whereas for the big dam the transport of selected material involves many miles of cartage, cartage which generally increases with the size of the dam. There would appear to be a great asset in the concentrated nature of the water in the large dam, though there is some considerable risk of collapse, especially in war time, but with the innumerable small storages spread over the whole country there is presented no major risk.

   Then there is the question of finance. In the big project there is never any expectation that the big outlay will ever be returned quickly, while with the farm storage project it is profitable in the way the landman and ordinary people understand profits. What is at stake? An amount of money is spent to start a farm irrigation project. The dam is constructed quickly in a few days or a week or two, the dam is successful, irrigation is profitable, and the capital cost of the work, be it loan money or farmer's capital, is paid back in a very short time. And there is in Australia not even any associated tax problem. The work is paid for from profits before the farmer's income is determined for tax assessment.

   There is no doubt that we need all the water that we can conserve and that we need it where we can make best use of it, and this will always be on the farm and grazing lands of the Commonwealth.

   As has been said, the undertaking is a vast one, but any great undertaking is made up of many parts as well as many people and much money, and to do the work quickly the undertaking must pay for itself as the work proceeds. Paying for itself simply means that a great number of people have to make a lot of money out of it, but as the people also have to pay for the work, then the scheme must be productive in the shortest time. If, as farm water conservation proceeds, the smaller parts of the whole scheme can be complete in themselves and be producers of good returns in a year or so, then the largest of projects can be undertaken with the minimum amount of money. As far as Government finance is concerned, no works approaching in size or importance that of the provision of adequate farm water supply could be undertaken so economically. A nationwide development worth literally thousands of millions of pounds could be projected and commenced with a comparatively small sum of money, a sum no more than has been considered lavish in the past for infinitely lesser public work, and which has been deemed to be well within our financial capacity.

   The big dam for irrigation and the farm size project for irrigation are both necessary for the realistic development of this country, but one aspect of this development, the farm project, has been grossly neglected.

   The true relative importance of the two water schemes, the big dam irrigation scheme and the farm-scale water project, may have been difficult for the reader to realise, yet I am hopeful, by the time I have reached the last reference to water, he will be in full agreement with me on the importance of farm water conservation, not only on account of its great value to the farmers and graziers, but because of its completely dominating influence on all national aspects of land use and water control.