AZ vs. CA:25 California Exhibits, Vol. XXV; Nos. 7501-7859

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were familiar with the negotiation of the Compact state that III(b) water was definitely allocated for use in Arizona in recognition of the present depletions being made in that state of the Gila River. 5. There is also some controversy in connection *ith the measure of Arizona's use from the Gila Piver. Arizona's position is thit her charge should be based on depletion of the virgin flow at the mouth of the Gila River. Others suggest that the charge to Arizona should be based on the formula "diversion minus return flow to the Gilt River." Calculations made by the Bureau of Reclamation show the following average figures for the period 1895-1943 inclusive: Virgin Inflow to Phoenix Region from all tributaries . . . 2,280,000 A.5. « flow Gila at Gillespie Dam............1,753,000 A.P. " " Gilo at mouth ...............1,300,000 .<,.]¦'. Estimated future flow Glie at mouth ........... 100,000 A.f. (exclusive of return flow from Colorado (.» River water diverted to GIIb Basin) fi* 6. Arizona would certainly very strenuously resist an assumption thf.t y jjy her charge under the Compact duo to use of Gila Fiver water should be 2,180,300 j* acre-feet annually, but might consent to recognition of a charge of Gilt River >y \/ use of 1,200,000 acre-feet (virgin flow s.t mouth minue estimated future flow at mouth). Ifith this assumption, tne basic amount of firm water e.vtilsble under Article 7(a) of th° Arizona jontr'tct would be limited oy the Colorado River Compact to 2,600,000 acre-feet &¦ follows: Ill(a) snd (b) to lower basin..........8,500,000 A.?. Less California limitation 4,400,000 A.F. Nevada contract 300,000 A.F. Use of Gila River 1.200.000 A.F. 5.9OO.OOO A.F. Net available for 7(a) of contract 2,600,300 A.F. 7. Despite the calculations shown in paragraph 6, it is Arizona1s ambition to secure 2,800,000 acre-feet of Ill(a) water from the Colorado River. Mexican Use 8. The Treaty dated February 3, 1944, guarantees to Mexico 1,500,000 acre-feet annually of Colorado River wet^r at the Mexican Boundrry. In ye1rs when there Is 3 surplus of water, Mexico will be permitted to use an additional 200,000 acre-feet. In years of extraordinary drought, her uses will be reduced in proportion to the reduction In uses within the United States. The Treaty