IRRIGATION. The operation of watering lands or causing water to flow over lands by artificial means for agricultural purposes.
"The word irrigation, in its primary sense, means a sprinkling or watering the best lexicographers give it an agricultural or spe cial signification, thus: 'The watering of lands by drains or channels' (Worcester) ; `The operation of causing water to flow over lands for nourishing plants' (Webster). The term irrigation as used in Colorado, in the constitution and statutes and judicial opin ions, in view of the climate and soil, is in its special sense, to wit : 'The application of water to lands for the raising of agricultural crops and other products of the soil.' " Platte Water Co. v. Irrigation Co., 12 Colo. 529, 21 Eac. 711.
At common law the right of the riparian proprietor to divert the water of a stream for the' purposes of irrigation was well recognized, and it was described as an arti ficial use of the water and not a natural use like taking the water for drinking, domestic purposes, and watering cattle, which would allow the use of all the water in the stream. A riparian owner could use for domestic pur poses and watering cattle as much of the wa ter of the stream as he chose, and if he found it necessary, take all the water in the stream, but in using the water for irrigation he was allowed to take only a reasonable amount of it and could not diminish the flow of the stream, so as to cause loss to other riparian owners ; Gould, Waters 217 ; Kin ney, Irrig. § 66 ; Tolle v. Correth, 31 Tex. 362, 98 Am. Dec 543 and note ; Fleming v. Davis, 37 Tex. 173; Tyler v. Wilkinson, 4 Mas. 400, Fed. Cas. No. 14,312; Ingraham v. Hutchinson, 2 Conn. 584.
This doctrine of the common law was sufficient for any irrigation that had been found necessary in England or in the United States east of the Mississippi River. But in what was once known as the Great American Desert and is now called the Arid Region west of the Mississippi, "there has grown up or evolved out of the necessities of the people and the exigencies of the communities interested, a great body of law, custom, regu lation, and judicial interpretation. These
statutes in general form the principle of prior appropriation as wrought out by the earlier miners, and embodied in federal law, and then by the states and territories, being steadily sustained by the courts, with a few exceptions, as the common law of an arid region such as ours. The development of the beneficial use of water has of course modified the practice of prior appropriations to a first or prior pro rata share of the natural waters, when taken from bed or source for industrial purposes ;" Senate Report on Ir rigation, 1890.
After the discovery of gold in. California had brought great numbers of people to that region, the miners developed a sort of code of their own, called the Mining Cus toms, which in 1851 were recognized by the legislature of California and made a part of the law of the state. By these customs a new principle in water rights was developed, called the Law of Priority of Appropriation, by which the person who first uses the wa ter of a stream is by virtue of priority of occupation entitled to hold the same, and may use all the water in the stream for the purpose of carrying on his mining opera tions ; Kinney, Irrig. § 104; Geertson v. Barrack, 3 Idaho, 344, 29 Pac. 42. This doc trine beginning in the Mining Customs and sanctioned by the legislature of California and the supreme court of that state, was afterwards approved by the supreme court of the United States, and congress not only passed acts which sanctioned the doctrine as regarded mines, but extended it to all other beneficial uses or purposes for which water may be essential, as irrigation for the pur poses of argiculture and horticulture and to milling, manufacturing, and municipal pur poses, in the Arid Region.
The rights of a riparian owner to the use of the water flowing by his land are not the same in the arid states of the west as they are in the eastern states. These rights have been altered by many of the western states by their conditions and laws because of the totally different circumstances in which their inhabitants are placed ; Clark v. Nash, 198 U. S. 361, 25 Sup. Ct. 676, 49 L. Ed. 1085, 4 Ann. Cas. 1171.