Irrio-ation alono- the Arkansas in Western 

 Kansas. 



BY E. C. MURPHY, C. E., 

 Member of the Amei'ioau Society of Irrigatiou Engineers. 



Some eight months ago the writer was asked to compute the horse- 

 power and give his opinion of a new design of wind-mill by a West- 

 ern Kansas man. Since then he has devoted considerable time to 

 the subject of irrigation in Kansas and to the use of wind-mills in 

 connection therewith. During the last two weeks of July he made a 

 trip with his wheel up the Arkansas Valley, visiting nearly all the 

 canals and their head works along the river up to Pueblo. The facts 

 presented herein he has gathered from observation, conversation 

 with canal officials and others, and from the U. S. Reports on irri- 

 gation in the arid region. He desires herewith to thank those who 

 have so kindly furnished him with maps and information on this 

 subject. 



We will consider briefly the rainfall, the evaporation, the winds, 

 the quantity of water available in the river, and the ground, the part 

 of this water used by the people of Colorado, and lastly the irrigation 

 works. In the discussion of the first two we will include the region 

 from Dodge City to Pueblo. 



The rainfall in this region may be seen from the records of four 

 places in it. Table I gives the names of these places, the length of 

 their record, the mean annual rainfall, the amount, percentage 

 amount, and least amount of rain which falls during the four irrigat- 

 ing months. May, June, July, and .\ugust. 



Dodge City 



Ft. Walliict.. 

 r^as Animas and 

 Pi L.vnu 

 Puei^lo 



Mean an- 

 nual rain- 

 fall. 



20 19 in. 

 13 31 '• 



12.36 '• 

 13 G7 ■• 



Rainfall in 

 4 m<is. 



Perc. fall | Least fall 

 in 4 mos. in 4 nios. 



It may be seen from this table that the mean annual rainfall in 

 nearly all of this region is about 13 inches; in the eastern part it 

 increases to about 22 inches. From 55 to 66 per cent of this mean 

 yearly precipitation falls during the four irrigating months. 



(117) KAN. r.NlV. QU.\K.. VOL. III-. NO. 3. lH>i. 



