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

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is now pending before the United States Senate for ratification. For the purpose of this study, it is assumed that Mexican uses of Colorado River water will be 1,500,000 acre-feet annually. Surplus Water 9. Under one interpretation of the Colorado River Compact, the amount of surplus water would be very negligible. There are some people who believe that the Colorado River Compact grants United States users in the basin the right to deplete the virgin flow at the mouth by m average of 16 million acre-feet annually. On this assumption the surplus water would be as follows: Average virgin flow at International Boundary 17,751,000 acre-feet Allocationsi Upper basin III(a) of compact 7,500,000 a.f. Lower basin Ill(a) of compact 7,500,000 a.f. Lower basin III(b) of compact 1,000,000 a.f. Mexican delivery, treaty 1.500.000 a.f. 17.500.000 " ¦ Surplus water 251,000 ¦ " It'is not known how the surplus water will be divided. The upper bag In intends to malce a claim for part of the surplus water. If the upper basin should claim 1/2 of the total surplus and the remainder should be divided 1/2 to California, 1/25 to Nevada, end the remainder to Arizona, the amount of surplus water accruing to Arizona would average 58,000 acre-feet annually. 10. By other interpretations of the compact, namely, that consumptive use represente diversion minus the return flow instead of stream depletion, the amount of surplus might be increased. In Mr. R. J. Tlpton1 s testimony of February 14 before the Senate Foreign Relations Committee, it was indicated that there might be so-called "salvage water" by converting pact channel losses to beneficial consumptive uses, possibly as follows! Upper Basin Streams .......... 400,000 acre-feet Lower « Main Stem.........380,000 " " Gilr River .............470.000 " " Total .......1,250,000 acre-feet 11. At the November 1944 meeting of the Committee of 14, Arvin B. Shaw, Assistant Attorney General of California, suggested th.t the surplus mipht be increased by applying Article III(a) of the Colorado annually instead of on an average basis. Following Mr. Shaw's suggestion I hove msde an analysis of the yearly virgin flows at Lee Ferry and find th<t if we use 15,000,000 acre-feet as the annual celling instead of the average for the upper and lower