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secured and were probably below the average; the total given by 

 Mr. Adams is therefore considerably less than the actual return 

 secured from the irrigated farms in the South Platte Valley in 

 Colorado. This complete utilization of the water supply and the 

 raising of high-priced crops ha\e been made possible only by the 

 development of methods of distribution and exchange which are 

 probably not equaled anywhere else in the United States." 



NORTH PLATTE AND TRIBUTARIES. 



The Xorth Platte River rises in North Park, Colorado, between the 

 Medicine Bow Mountains on the east and the Park Range on the 

 west, which, with the Continental Divide on the west, form a horse- 

 shoe-shaped area comprising about 1,700 square miles in Colorado. 

 The valley in this section has a general altitude of about 8,000 feet, 

 and the mountains surrounding it rise to 10,000 to 12,000 feet. The 

 streams draining these mountains unite in the center of North Park 

 to form the North Platte River. Near the Colorado- Wyoming line 

 the river enters a succession of canyons separated by stretches of 

 rolliuir hills. This formation extends for about 20 utiles, beyond 

 which the river enters a rolling country. The hills are not so high 

 as those farther south and occasionally recede from the stream, 

 leaving areas of bottom land varying from 10 to 1,000 acres in 

 extent. The„se bottom lands are irrigated, usually not from the 

 river itself, but from mountain tributaries. Beaver, French, Bnish, 

 Cow, and Encampment creeks enter the river in this section. Far- 

 ther down the valley broadens until it reaches a width of 1 to 3 

 miles on the west side and an average of about 4 miles on the east. 

 This valley extends for 50 miles to the Union Pacific Railroad at 

 Fort Steele. In this valley the river receives the discharges of 

 Jack, Sage, Spring, and Pass creeks. The estimated area which 

 can be reclaimed by irrigation in this valley is about 125,000 

 acres. The river receives its greatest perennial supply from these 

 tributaries entering it in the section above Fort Steele. Irrigation 

 is practiced to some extent in the valleys of these tributaries. 



From Fort Steele the river flows through precipitous hills for about 

 35 miles to the Seminole Mountains. The country on both sides is 

 badly broken, and is used only for grazing. In this section the river 

 receives the discharge of the Medicine Bow River, which rises in the 

 Laramie Mountains. Irrigation is practiced along the course of the 

 Medicine Bow. From the mouth of the Medicine Bow to the mouth 

 of the Sweetwater River the land along the North Platte beeomes 

 more and more sandy, until vegetation practically disapj^ears. From 

 the mouth of the Sweetwater the river still flows through broken roll- 



aV. S. Dept. Agi-., Office of Experiment Station.s Buls. 92, 118, and i:U. 



