Irrigation in the United States

Irrigation—the act of app lying water artificially to soil to provide moisture for plant growth—has been practiced since the beginning of recorded history. Great civilizations of antiquity were supported by irrigation agriculture. The Indians were practicing irrigation when the Spaniards came to the Americas. Irrigation agriculture as a major industry in the United States began with the Mormon Colony in Salt Lake Valley, Utah (1847) and the Union Colony at Greeley, Colo. (1870). Early development was most rapid in Utah, Colorado, California, and Idaho. Prior to 1900, practically all work was done by private enterprise and private capital, during which time about 7,000,000 acres were irrigated. From 1900 to 1952, an additional 12,000,000 acres were brought under irrigation by private enterprise and nearly 6,000,000 acres were provided with a full or a supplemental water supply by the Bureau of Reclamation, United States Department of the Interior. During the past decade, supplemental irrigation in humid and subhumid areas has grown rapidly.