Relation of Scientific Irrigation to Permanency of Civilization

Relalion of Scientific Irrigation to Permanency of Civilization* By George Dewey Clyde In the minds of those living in the great centers of the hrnnid areas of our country, there is much speculation concern- ing the future welfare of a commonwealth based upon irriga- tion. Even among our national leaders there are some who fear that our western civilization, based as it is on irrigation, cannot long endure. To illustrate, in 1913 Dr. Beverly T. Gal- loway, then chief of the Bureau of Plant Industry, was re- quested to appear before the Congressional Committee on Ap- propriations to give his opinion concerning the proposed ap- propriations for development of western irrigation. Dr. Gal- loway made the following assertion: "As far as I know, there never has been any long continued successful irrigation agri- culture in any climate anywhere in the world." Do you real- ize what he meant when he made that statement? Dr. Gal- loway meant that the green fields, fertile farms, beautiful towns and cities that surround us are only temporary. He meant that the wonderful achievements brought about by the artificial ap- plication of water are doomed to revert to the barren wastes from whence they came. In other words, he maintains, as do many of our national leaders, that a civilization based upon ir- rigation cannot be permanent. Let us see if history bears out this contention. Irrigation is one of the oldest arts used by man. It has been practiced for countless centuries by the Egyptians, Arabians, Assyrians, and Chinese, and from time immemorial has formed a basis of agriculture of the countries bordering on the Mediterranean. The Valley of the Nile h&s ever been fa- mous for its irrigation practice. The plains of Assyria and Babylonia were once covered with an immense system of ir- rigation canals, some of them hundreds of miles in length. The Romans constructed extensive irrigation works, many of which are still in use. These countries were the centers of early civilization, and due to the single fact that they were based up- on irrigation agriculture, their civilization has endured in the *Valedictory address delivered at the graduation exercises of the class of 1921, at the Utah Agricultural College.

28 IMPROVEMENT ERA past, and there is absolutely no reason to doubt the permanency of their civilization in the future. There are instances in ancient history, however, and no doubt Dr. Galloway was thinking of these when he made the above assertion, where highly civilized countries based on ir- rigation have decayed and are now barren wastes, but it is only when the reservoirs which store the water and the canals which distribute it are destroyed by revolutions or neglect, or the land ruined by excessive irrigation that the once fertile fields revert to deserts and swamps. One of the earliest examples of irrigation works of which we have record is interesting because it illustrates not only the prosperity which accompanies a well-managed irrigation sys- tem, but also the ruin and desolation which, in a country de- pendent on irrigation, inevitably follows neglect of the proper maintenance of its irrigation works. Babylonia, which is the part of Mesopotamia occupied by the ancient Babylonians, is described by Herodotus as densely populated and thickly stud- ded with great cities and prosperous towns founded upon irri- gation agriculture. In the course of centuries, the canal systems of Babylonia suffered many vicissitudes. Time and again the canals were ruined by floods and neglect of works, water was applied to the soil in large quantities without regard to the requirement of crops. With the destruction of the canals, and water-logging of lands by excessive application of water, food production became impossible and Babylonia rapidly sank into the state of barren desolation which it now presents. In reality, it was lack of scientific knowledge of irrigation and not irrigation in itself, as is believed by many men, that caused the failure of the ancient Babylonian civilization. Why did the primitive man apply water to the dry soil? No doubt he had observed that where the land was hard and dry, no vegetation grew, and that where vegetation was most abundant, the soil was moist and warm. Today we know there are three prime factors of crop production: moisture, soil fer- tility, and temperature; of these, moisture is by far the most essential. If man could control these fundamental factors, the basic problems of food production for a civilized people would be solved. In an arid section, as a rule, the soils are deep and in- herently fertile ; the sunshine is abundant. The temperature cannot be controlled, but irrigation supplies moisture which is more vital than either heat or soil fertility, and may be con- trolled by man. Irrigation not only supplies a deficiency of moisture but supplies it when it is most needed. There are

RELATION OF IRRIGATION TO CIVILIZATION 29 but few parts of the earth's surface where annual rainfall is economically distributed throughout the year, so that man can depend upon natural moisture to mature his crops. In the arid sections where scientific irrigation is practiced, man no longer depends upon natural conditions for sustaining life, be- cause he controls the life-giving moisture and applies it to his crops at the proper time. In the ancient world, the most populous sections are found in regions originally desert. In such regions soil fertility can be utilized only by irrigation, and wherever irrigation is resorted to, the density of population, the existence of great wealth and of empires are always found. The Valley of Po, in Northern Italy, furnished a living ex- ample of this fact. Here there are eight million people. The climate of this valley, is not especially favorable, for the tem- perature often goes down to 10 degrees, yet this little valley provides for eight million people because one of the most im- portant factors of food production, moisture, is under the con- trol of man. In modern history, the recent rapid growth of Southern California with her beautiful cities, orchards, and farms is the most remarkable instance of rapidity of growth associated with maturity of civilized conditions to be found anywhere. This exceptional instance of community life of Southern California, and the exaltation of civilization there is due to the single fact that the entire superstructure of that commonwealth stands upon the science of irrigation. Take from the advanced civil- ization of Southern California all that portion due to irri- gation, and its splendid cities would relapse into the romance of adobe hamlets and the tropical luxuriance of its orchards and its avenues and farms would revert to their original condition of arid solitude. Lizards and cacti would again reign supreme. The "Mormon" people were the first Anglo-Saxon to prac- tice the artificial application of water in America, and Utah stands today the greatest monument to irrigation in the word. When our fathers and grandfathers, the pioneers, came to Utah, in July, 1847, they found here an arid desert; they converted it into a fertile garden and founded upon irrigation agriculture this great commonwealth in which we now live. Our civilization can fail only when our agriculture is de- stroyed. Irrigation agriculture is largely controlled by man; therefore, our civilization, based as it is upon the scientific application of water to the soil, will endure as long as our public intelligence and vigor lasts. But you may say as did Galloway and others that we have no assurance of the permanence of the water supply or of the

30 IMPROVEMENT ERA soil fertility now making the beauty of Utah, Idaho, California, and other irrigated sections possible. The rapidly increasing intelligence and scientific knowledge of our western civiliza- tion, however, assures the permanence of both the water sup- ply and soil fertility. The massive storage dams, great head- gates, steel flumes, syphons, and concrete tunnels built by the engineering profession during the last few decades assure the control of our water supply. Likewise, the application of the science of irrigation, of which the Babylonians knew noth- ing; to the prevention of seepage losses of water from canals; to the smoothing and leveling of land in order to reduce the runoff losses; to a study of the capacity of soils to absorb and retain water; thus preventing excessive losses by deep percola- tion through the soil and subsequent water-logging; and to the economical use of water, supplemented by drainage where neces- sary— to all of these problems the application of science doubly assures the permanence of the fertility of our irrigated soils, thus making scientific irrigation the basis of a permanent civiliza- tion. In the early days of irrigation, the easily accessible streams were diverted first. The first canals were taken out near the bottom of the valleys to avoid expensive construction. As time went on and more land was brought under cultivation, canals were built higher up, until the available water supply was en- tirely appropriated. Up to this point in our irrigation development, there was plenty of water for all during the spring floods, but later in the season only those with prior rights to the water had suf- ficient to mature their crops, and the rest were burned out. By means of storage reservoirs, the rainfall over the entire drainage basin is collected and held till the crops require it. Thus storage reservoirs not only increase the available sup- ply of water but they stabilize irrigation agriculture. On prac- tically all of the projects built by the United States Reclama- tion Service, large storage reservoirs have been built to store the spring floods so that the water can be distributed over the land when most needed. Our huge storage reservoirs and di- version works, our headgates and concrete-lined canals, insure permanent supply of moisture, stabilize our agriculture, and thus tend to make our civilization everlasting. The water supply of arid regious is the real limiting factor in our agricultural development, and in consequence, measures must be adopted to regulate and control its use. The import- ant problem is to determine the actual water requirements of crops under field conditions and to make use of this informa- tion as a basis for arriving at an economical use of water. The

RELATION OF IRRIGATION TO CIVILIZATION 31 problem is a complex one because so many variable factors enter, water requirement of crops, climate, fertility, texture, chemical composition, and depth of the soil enter in all their complexities, making the determination of an economical use of water extremely difficult if not impossible of a fixed solu- tion. According to the 1910 census, the average amount of water used per acre of irrigated land was enough to cover each acre to a depth of 4.75 feet. Dr. Samuel Fortier states that at that rate, there is sufficient water available in the seventeen western states to irrigate 50,000,000 acres of land. The arable area in the same states is approximately 350,000,000 acres. Therefore it appears that the future development of the western states depends in no small degree on the care exercised in alloting and using our limited water supply. Out of every four gallons of water diverted from the river or stored in a reservoir only one gallon is now utilized for pro- duction of crops. What becomes of the other three gallons? It is not only lost to beneficial use, but it fills up the under- ground reservoirs and drowns the lowlands. The seepage losses from canals alone frequently amount to two gallons out of every four diverted from the river. Another one-half gallon is lost through surface run-off due to poor preparation of the land. Also one-half gallon is lost through deep percolation, thus making a total loss of three gallons out of every four, due to loose, careless irrigation practice. By applying the scientific knowledge of irrigation that has been developed in the past few decades, first to the construction and maintenance of our canal systems; second, to the prepara- tion of land so as to permit the uniform distribution of water, and finally, to a study of the soil conditions and water require- ment of crops, it has been demonstrated that we may economic- ally utilize 75 per cent of our total water supply; whereas, we are now utilizing only 25 per cent. Moreover, by a more eco- nomical use of water on our lands, the problem of water-log- ging, which was the real cause of Babylonia's ruin, will be largely solved. Under the best irrigation management yet shown to be feasible, there is still one gallon of water out of every four diverted that is lost, and this one-fourth will con- tinue to aid in the water-logging of our low-lands. However, scientific irrigation which assures the premanency of our civil- ization, provides a remedy which will take care of this 25 per cent of our water supply will also reclaim the areas that have become water-logged through careless, unscientific methods of applying water to our soils. Consistent drainage is the remedy. It is true that some of our lands have become water-logged

32 IMPROVEMENT ERA through I wasteful DM <>!' water; but that properly installed drainage system* will reclaim such lands has been fully dem- onstrated. Water-logged lands, due to excessive irrigation, are not as Mr. Galloway infer-, a permanent injury, but a temporary one that can be and is being removed on our water-logged lauds. From a consideration of the above questions, we can prop- erly make the following conclusions: The civilization of Babylonia did not fall because it was founded on irrigation agriculture, but because the Babylonians failed to recognize the fundamentals upon which irrigation de- pends. They knew but little about soil fertility or about deep percolation, or runoff water losses, and there are no evidences that the art of drainage was ever known to them. Today our engineers are building huge storage and di- version works; and our scientists are studying the soil, the water requirement of crops, the losses of water in conveyance, the runoff and deep percolation losses, the methods of drainage, and removal of alkali. As a result of the great work of our scientists and engin- eers, we can now apply the principles of scientific irrigation to our irrigation practice. Of these principles, it appears that the Babylonians knew nothing. Supplemented with drainage, where necessary, the application of these basic scientific prin- ciples assures the permanence of our water supply, and the permanence of our soil fertility; and thus, the permanence of a civilization based upon scientific irrigation. The words of Mr. A. F. Doremus, former State Engineer of Utah, express a true tribute to irrigation: "Born of ob- scurity and despised as menial, irrigation has grown to be king of the rapidly developing west, and by virtue of its power to bless and benefit mankind, it has compelled the respect and admiration of all. Its promise is potent, its progress sure."