The Colorado River and Arizona's Interest 

 in its Development* 



By G. E. P. Smith 



It is nearly four hundred years since Spanish explorers discov- 

 ered the canyons of the Colorado River. During these centuries man- 

 kind has coped with many problems and has surmounted great obsta- 

 cles. But the six hundred mile stretch of canyon of the Colorado of 

 the West is still under nature's control. No stone has been turned to 

 impede the flow of water ; no revolving wheel converts the power of 

 the flood to useful purposes. 



The development of the great river is a stupendous problem. 

 Not alone is the layman staggered by the difficulties involved .and 

 by the immensity of the stakes, but the engineer is challenged and is 

 struggling to conceive of the gigantic works that are required, — dams 

 of twice the height of the highest dam yet attempted, reservoirs 

 twelve to twenty times as large as the largest artificial reservoir in 

 the world, and power generation on a prodigious scale. 



GEOGRAPHY AND IRRIGABLE LANDS 



Before presenting the problems of the Colorado River it may be 

 helpful to review the geography of the region and to present a digest 

 of the character and extent of the water supply. 



The drainage basin of the Colorado is shown in Fig. 1. It in- 

 cludes parts of seven states, — the southwestern part of Wyoming, the 

 western half of Colorado, the eastern half of Utah, a strip along the 

 west side of New Mexico, all of Arizona except the southeast corner, 

 the southeast part of Nevada, and the southeast edge of California, — 

 in all, 251,000 square miles. The watershed on the east side of the 

 basin is the Continental Divide, from the Mexican boundary line 

 almost to Yellowstone Park. All of the northern half of the basin, 

 and part of the southern half, consists of high, mountainous country, 

 on which there is a heavy annual precipitation. 



Until a year ago that part of the stream system draining western 

 Colorado was called the Grand River. In the southeastern part of 



•An address delivered at the Annual Farm and Home Week at Tucson, January 18, 1922. 

 It was voted by the audience that the address should be published, and in response to the 

 widespread demand for authentic information on the subject, the paper is included in the 

 kulletin series. — Publication Committee. 



