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Table 8-10!. Selected crop. and double C'I'Opplilgpo"ibilitie., Roo.evelt Water CotIBervctiotl District. ro Double Cropping Possibilities' 00 Crops Wheat Barley Lettuce Sorghum Watermelon en - WJ Alf.lf. Cotton x Barley Whe.t Sorghum x x x x x Lettuce x x x x x Watermelon x x x Grapefruit Oranges/Tangerines Sugar Beets acrops under these columns are those assumed to lead in the double cropping rotation. Table 8-108. Yields of major crop. in the Roo.evelt Water CotIBe",atiotlDistrict, 1968-1979, (totlB/acre). a 9S Percent 1968 1969 1970 1971 1972 1973 Confidence Interval Alfalfa 6.00 6.00 6.00 6.00 6.00 6.00 6.00 :l: 0 Barley 1.97 1.70 1.99 2.04 2.14 2.16 2.00 :l: 0.17 Wheat 1.86 1.86 2.25 2.55 2.70 2.76 2.33 :l: 0.42 Sorghum 1.92 2.18 2.24 1.82 1.71 2.16 2.01 :l: 0.23b All Cotton 2.23 2.17 1.92 2.14 2.01 1.96 2.07 :l:0.t3 All Cotton Seed 0.90 0.95 0.97 0.95 0.85 0.88 0.92 :l: 0.05 Carrots 13.50 13.50 9.00 12.00 6.50 13.00 11.25 :l: 3.02 Lettuce 4.72 10.25 10.23 12.83 7.75 13.50 9.88 :l: 3.42 Watermelon 14.00 14.00 8.50 12.00 13.00 10.00 11.92 :l: 2.36 Sugar Beets 20,00 19.00 15.00 21.40 22.50 23.00 20.15 :l: 3.08 Grapefruit 18.00 12.40 22.00 10.45 18.75 10.80 15.40 :l: 5.06 Lemons/Limes 19.25 10.90 19.25 15.30 16.18 :l: 6.33 Orangestrangerlnes 5.93 10.05 13.75 6.70 12.35 10.30 9.85 :l: 3.22 aYields prior to 1972 from Salt River Project crop reports. b48Q..pound bales per acre. Source: Annual Crop Production Reports, Roosevelt Water Conservation District, was broken down into 2,250 acre. of farm.teads, roads, ditcbes, and drain.; 660 acres of urban and suburban residential, commercial, and industrial; and 81,663 acres irrigated for harvest or pasture (Guidelines to Production Costs and Practices). Irrigation water is pumped entirely into a concrete-lined distribution system (ArIzona Water Comnilsslon mea). The estimated pumpage is 160,000 ac ft per year within 106 active wells. Part of the water comes from wells within the western bounda- ries of the Salt River Valley Water U sera Association and part from wells within the RID boundaries. In addition, a portion is also obtained from wells along the Agua Fria River to the east of the old river bed. Nearly all are high in salt content as is shown by published analyses of a few selected wells (Table 8-108). Water samples taken directly from the main canals have run around 1,800 mg/l TDS (McLouth, personal interview). If this figure is too low, as nilght be indicated by. 'l'able 8-99, the replacement of RID groundwater by Central Arizona P1'<lject (CAP) water could eliminate tbe worst wells and help bring the water froll\ the remaining wells down to somewhere near this estimate. The solis of tbe RID are predominantly well drained. This has made It possible to use the present water supply which has a relatively high salt content. Whatever the amount of CAP water allotted it will serve to Improve the district's water quality by dilution, at least until the CAP water reacbes 1800 mg/l TDS. Since the RID has requested 75,000 ac ft. It may not be too far off to assume an allotment of 40,000-50,000 ac ft. If they are allotted 40,000 ac ft, they will still have to pump 120,000 ac ft of groundwater to meet their commitments. Table 8-109 shows the effect of increasing salinity in the CAP water on the resulting blend. If the district Is allotted 50,000 ac ft and pump 110,000, the blend will be only slightly lower in TDS with the present 188