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" " 8. WJler diverLed. Ttle estimated aVQr~ge annual diversion of water by the 17 cunuls (direcl flow plus reservoir relcu'.s) wus J02,100 acre- feet. The JITIount Jiverted viJried greutly from YC.1f Lo yeiJr. Most canals C'xperienced J minimum diversion from the SouLh Pl,jlLe Hive!" during 19~-t and 1961. Maximum diversions generally occurred durin'.J J')47 Jnd 1'J52. ~, ., . The eslimated aver<:lg€ annual ctlnal 1055 was 81\,700 <!cre-feet or 29 percent of the WiJter diverted. Thus, an ilnnual Cl vO.r ,1 ('j c, of 217,400 acre-feet of surfJce waler was esLilnaled to be aVijil~b]G ~L the farm hCiJuqa leG. The eslim.:1led avera'J€ annual clmourlt of wut.er purnp(~J fronl groundwater sources for lCJnd under lhe I.' canals Il/dS eslirTI,]led Lo bl::' 1I1o,6C(J Jcre- feet. Thus, the estimated total average anrnJal supply of w.lcr al the farm headgutes was 366,000 acre-feet or 2.94 acre-feet per ocre. Ground- water provided obout 40.6 percent of the total supply aL the for~ headgaLe. Unly u very minor i3H\ount of wuter \',1-15 U50d for irriq.1.lion during the months of November, December, Jilnuary, februJry ond Milrch. fhe estimated cJvcr(l<je <lnnuul loLlI water supply <.It the ciJncl r1V'2f heaclgJtes plus res- ervoir releases J.nd groundwalpr p~ITlped was €stim.JtecJ to be ,150,/100 Jcre- feet. (Some minor discrepilncies will be noted in some of the above totals due to rounding of figures to the nearest 100 acre-feet). 9. Estimated full or ideal water suppl y at farm heildqute~.!. The full water supply dt the farm heodgate WilS computed by the !Jure;;u of Reclilmation using (I) a combination of the Lowry-Johnson and the Thornthw"ite methods to determine the consumptive use of wilter by crops and (2) ~n ilssumption of a 60 percent irrigation efficiency in the application of water to supply the consumptive use requirements for each of the 11 canals. " ., ~ The estimilted full water requirement ill the farm head')dte varied from 1.59 to 3.19 ilcre,feet per acre with iln average ilnnuill heildgdLe wilter requiremont of 2.4~ Jcre-feet per acre or 0 total of 304,2UO ucre-feet for the 17 canols. Monthly requirements averaged 0.U3 ilcre-foot per ilcre for i,prIl, 0.14 for May, 0.47 for June, 0.(,6 for July, 0.60 for j,ugust, 0.36 for September, ..nd 0.13 for October. ^n assumed average of 60 percent irrigalion efficiency for the combined 17 canals appears to be reasonilble; however, beciluse of different soil con- dition, kind of crops produced and methods of irrigalion for each canal, it is not reasonuble to expect the irrigation efficiency would be identic"l for each c.1nill. 10. Esti~2!ed fulL-requirement g!_cen~]~adqole. The canal heildgate requirement includes the full requirement .t the farm headgote plus conal lo..e.. The e.timated average annual reguirement Jt the canal headgates was e.timated by the 8ure,lu of RecLmalion to be 38H,900 acre-feet. ') 11. E.t.imgj;Q2-sur:n]-'!. or .;;hortaqe at lhe_canJl he,dqdtes. j,n estimated annual average surplus of 61,500 acre-feet for the 17 cilnals was found as the difference between the total heJdyate supply and the total heildgate requirempnt. However, 1\ of the 1~1 c,]n~\ls expcr1cnccd an dver,1gc ~>hortiJge dur i ng the 15 yeJrs ond ,11 so hod " shortaljD SO .percen L 0 f t.he 1 S-yoar time period. /-1 so muny di tches experience shur loges duri ng cri ti cill months, hut show an i3nnual surplus bccliuse of excessive w,1tcr U~~e duriny other months. .' " .