46 



BULLETIN 339, U. S. DEPARTMENT OP AGRICULTURE. 



crops. The table confirms the conclusion reached from Table X, 

 that normal projects are about equally divided between (1) hay and 

 pasture and (2) grain and other miscellaneous crops. ■ 



The number of acre-feet diverted each month by each system was 

 determined and computed, and Table XXIII shows the number of 

 acre-feet diverted for each acre irrigated during each month of each 

 sfeason. 



Table XXIII. — Quantity of water diverted for each acre irrigated during each month of 

 irrigation season for ten different canals. 



Name of canal. 



Year. 



Acre-feet diverted for each acre irrigated. 



April- 



1-15 16-30 



May. 



June. 



July. 



Au- 

 gust. 



Sep- 

 tem- 

 ber. 



October- 



Total. 



Riverside 



Do 



Farmers' cooperative . . 



Do 



Farmers' Union 



Do 



Settlers' 



Do 



Boise Valley 



Do 



Eureka 



Pioneer 



Do.. 



Randall 



Clark and Edwards . . . 

 South Side Twin Falls. 



Do 



1911 

 1912 

 1911 

 1912 

 1911 

 1912 

 1911 

 1912 

 1911 

 1912 

 1911 

 1911 

 1912 

 1912 

 1912 

 1912 

 1913 



0.08 

 .11 

 .04 

 .00 

 .14 

 .25 

 .04 

 .00 

 .14 

 .00 

 .00 

 .11 

 .14 

 .00 

 .00 

 .10 

 .09 



0.43 

 .63 

 .38 

 .08 

 .48 

 .68 

 .16 

 .01 

 .27 

 .00 

 .05 

 .40 

 .00 

 .00 

 .00 

 .14 

 .11 



1.40 

 1.74 

 1.31 

 1.07 

 1.25 

 1.32 

 .42 

 .49 

 .63 

 .46 

 .38 

 .91 

 1.12 

 .00 

 .31 

 .60 

 .83 



1.46 



1.98 



1.36 



1.26 



1.41 



1.23 



.72 



.69 



.59 



.50 



.33 



.97 



1.62 



1.58 



2.59 



1.10 



1.12 



1.16 



.94 



1.25 



1.07 



.71 



.70 



.64 



.68 



.34 



1.09 



1.03 



2.25 



3.00 



1.23 



1.25 



0.79 



1.19 



.44 



.58 



.55 



.53 



.46 



.54 



.42 



.38 



.35 



1.01 



.98 



1.99 



2.67 



1.13 



1.21 



0.79 

 1.23 

 .36 

 .56 

 .45 

 .45 

 .42 

 .34 

 .30 

 .37 

 .34 

 .83 

 .82 

 .81 

 2.04 

 .61 

 .73 



0.50 

 .62 

 .28 

 .17 

 .13 

 .00 

 .11 

 .10 

 .12 

 .00 

 .03 

 .12 

 .31 

 .25 

 .34 

 .22 

 .20 



0.15 

 .00 

 .19 

 .10 

 .00 

 .00 

 .00 

 .00 

 .00 

 .00 

 .02 

 .00 

 .00 

 .00 

 .00 

 .16 

 .17 



7.14 

 9.49 

 5.52 

 . 4.76 

 5.66 

 5.53 

 3.04 

 2.87 

 3.11 

 2.39 

 1.84 

 5.44 

 6.02 

 6.88 

 10.95 

 5.29 

 5.71 



Average for month 



Per cent of season's diver- 

 sion 



.22 



4.08 



.84 

 15.6 



1.21 



22. 43 



1.23 



22.83 



16.5 



.67 

 12.43 



.20 

 3.71 



.05 

 .93 



5.39 

 100. 00 



The investigation has demonstrated the adequacy of 2 acre-feet 

 (p. 32) for diversified crops on clay loam soils, provided there is no 

 waste, and the measurements of the use of water by the farmers in 

 typical districts show that more than 2.5 feet per acre is seldom 

 delivered to or used upon the land. The quantities diverted by the 

 above projects, however, which represent the normal use in Idaho, 

 show that they divert much more than is required for the crops on 

 the farm. A comparison of these diversions with the quantities 

 required and used on the farms would indicate (1) that water is 

 wasted by the canal systems both early and late in the season; (2) 

 that a considerable supply is required for domestic purposes and stock 

 water; and (3) that the losses from seepage and evaporation in trans- 

 mission, and from careless use, must be far larger than many have 

 realized. The quantities shown as having been diverted per acre in 

 the preceding tables are known to be very nearly accurate, and, con- 

 sidering the fact that it has been found necessary to divert these 

 quantities under normal Idaho conditions, these data must be given 

 careful consideration when designing projects with scanty water 

 supplies-; '■•-'- ■■ ■ - - •" 



