CHAPTER X 



IRRIGATION 



Since ancient times, irrigation has been practiced in 

 semi-arid and arid countries. Applying water to grow- 

 ing crops by carrying it out into the fields through 

 ditches and allowing it to spread over and percolate 

 into the soil, has assumed immense proportions in the 

 more arid regions of the United States. Even in the 

 states further east than the Mississippi river, irrigation 

 is found very profitable under some conditions. The 

 national government has inaugurated a very large 

 scheme of co-operation in which, through an organiza- 

 tion called the Reclamation Service under the Depart- 

 ment of the Interior, it joins with many landowners 

 and aids prospective purchasers of public lands in 

 the construction of immense systems for irriga- 

 tion. In some cases canals are built taking water 

 directly from streams to the land. In many cases dams 

 are necessary to raise the level of the water in the 

 streams from which the water is drawn. In other cases 

 immense dams are made to create great storage reser- 

 voirs in which supplies of water are accumulated to be 

 used when the crops most need them. The United 

 States Department of Agriculture also is doing much in 

 co-operation with private parties or organizations who 

 are irrigating lands. This department is aiding not only 

 in making plans for irrigation plants both by the gravity 

 plan, and by pumping by wind or other power, but it is 

 also studying methods of distributing the water to the 

 farmers and to their crops, and is investigating methods 

 of farm management under irrigation. The engineering 

 plans being worked out by the Reclamation Service alone 

 involve many millions of dollars and with the co-opera- 

 tion of the United States Department of Agriculture 



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