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002059 62 ASSEMBLY INTERIM COMMI'I'TEE ON WATER decreasing the deficiency, in terms of overdraft, to about 1.5 mil- lion acre-feet annually. It is expected that, from further studies now being carried out, adjustments will be necessary in estimates of overdraft.4a Irrigation effieiency is another factor to be considered with regard to the overdraft. The Budget Bureau of the Executive Office of the Presi- dent noted that the Burcau of Ueclamation estimated irrigation effi- ciencies in the Central Arizona Project service area of only 50 percent.5 It can be seen that although overdraft conditions now exist in Ari- zona, the water requirements of the Central Arizona Project service area will increase only from 3,080,000 acre-feet at the present to 3,890,- 000 acre-feet in the year 2000, an increase of 800,000. The requirements of the entire Arizona area will increase from 3,985,000 to 5,485,000 by the year 2000, an increase of approximately 1.5 million acre-feet. It is obvious from this table that the major area of water deficiency in the Pacific Southwest is in Arizona through the year 1990 or 2000 (in- asmuch as we have seen that southern California areas are basically in balance until that timc assuming a guaranteed supply of 4.4 to Cali- fornia from the Colorado River). Referring to previous information on the water supply in the Colo- rado River, it is recognized that if California were to receive a 4.4 mil- lion acre-foot priority the entire 1.2 million acre-feet water supply of the Central Arizona Project would not be available through the year 2000. A substantial part of the water supply of the Central Arizona Project, however, would be available even with the 4.4 priority to California. All of these assumptions however, include a continued annual over- draft in Arizona. The ability of the area in Arizona to continue to sustain this overdraft is a matter beyond the scope of this report. It should be pointed out however, that estimates by the State Department of Water Resources have indicated that the annual overdraft in Cali- fornia's San Joaquin Valley is in excess of 2,000,000 acre-feet a year. NEW MEXICO AND UTAH According to the revised Pacific Southwest Water Plan report: "Present pumpage in that portion of New Mexico tributary to the Colorado River, essentially limited to the Gila River Basin, is esti- mated to be about 25,000 acre-fect annually. It is indicated that there has been no long-term water level decline, although there may be localized deficiencies. No data are available to estimate the relatively minor quantity of gross pumpage in the part of Utah tributary to the Colorado River." 6 Chapters III and IV of the Pacific Southwest Water Plan revised report include detailed information on water supply and demand based upon the Bureau of Reclamation's estimates of water supply in the Colorado. ill U.S. Bureau of Reclamation, Supplemental Information Report on Cent'i"al A'i'i.~01W P'i"ojectJ Arizona, January 1964, at 21. Ii Hearings on S. 1658, Part II, op. cit... at 276_ 6 pacific Southwest Water Plan, Revised January 1964. at 3-6.