82 BULLETIN 1026, U. S. DEPAETMEiSTT OF AGRICULTURE. 



engineers and liydrographers to determine losses and gains in the 

 streams, the return flow, characteristics of flow peculiar to each 

 stream in flood and at low stages, and other pertinent facts. With 

 this information at the disposal of the administrator a fairly satis- 

 factory distribution would be possible immediately upon his taking 

 office and not after 2 or 3 years of painstaking and perhaps costly 

 experimenting. 



The duty of water figured for the river as a whole is 1.67 acre-feet 

 per acre; or, expressed differently, each second-foot of the average 

 annual discharge irrigates 434 acres. This very high duty is made 

 possible only by the reservoirs of the valley. To attain a duty as 

 high without stored water, the crops grown would have to be limited 

 to the grains. 



The consumptive duty for the valley is estimated not to exceed 

 1.25 acre-feet per acre. 



Nonproductive and waste land averages approximately 15 per cent 

 of the area under irrigation. 



The areas irrigated by the various canals lie in very compact 

 bodies, which promotes to a i3ronounced extent the efficient use of the 

 wat-er supply. 



The area actually irrigated in the valley proper in 1916 was 218,000 

 acres: in 1917, 225,700 acres. Any marked extension of the area irri- 

 gated is improbable. 



The majority of the canals of the valley are cooperative enter- 

 prises and present no unusual features of organization. The fact 

 that the majority were cooperative from the beginning has an im- 

 portant bearing on the development of the valley. Such systems 

 were run for the mutual benefit of water users and there was very 

 little of the paralysis of development caused elsewhere by overpro- 

 motion for profit. 



The great majority of laterals serving more than 2 or 3 users are 

 controlled by incorporated cooperative stock companies, and this form 

 of organization for laterals is to be recommended. By it the delin- 

 quent water user can, in an impersonal way, be made to live up to 

 his obligations. 



Canal structures follow common designs and concrete is replacing 

 wood for construction purposes. The systems of the valley have long 

 since passed the stage of development where cheap construction was 

 permissible in order to reduce first costs, to keep down interest 

 charges, and to permit expansion. Future construction should be of 

 the most substantial character. 



The rating flumes of the canals are generally most unsatisfactory 

 and should be replaced by structures better suited for the purpose. 

 They should be of the same cross section as the canal and should 

 neither constrict nor widen the channel. They should be on grade 



