OCR Text |
Show pact-required deliveries to the Lower Basin. If the Central Arizona Project is constructed, major deficiencies in its water supply could occur sometime about 1990-2000 - 25 to 35 years from now, or 15 to 25 years after the project would begin to operate. Portions of the summary and the conclusions of the report entitled WATER SUPPLIES OF THE COLORADO RIVER AVAILABLE FOR USE BY THE STATES OF THE UPPER DIVISION AND FOR USE FROM THE MAIN STEM BY THE STATES OF ARIZONA, CALIFORNIA AND NEVADA IN THE LOWER BASIN are quoted herein: Summary "Based upon the recorded historic flow of the Colorado River, it appears that nature has decreed that the river will not supply enough water to support the apportionment made by the Colorado River Compact to the Upper Basin; an amount of 7.5 maf for consumptive use from the main river to the states of Arizona, California and Nevada; and the allocation to Mexico by the Mexican Water Treaty of 1944. The U. S. Supreme Court in Arizona vs. California, et al., 373 U. S. 546, agreed with the Special Master that the Secretary's (of Interior) contracts with Arizona for 2.8 maf and with Nevada for 0.30 maf of water, together with the limitation of California to 4.4 maf effect a valid apportionment of the first 7.5 maf of main stem water in the Lower Basin. All those contracts provide for the stipulated deliveries of water subject to the availability thereof. The Court recognized that shortages might occur. Where the words "apportionment" or "apportion" appear hereinafter relating to the beneficial consumptive-use values of the states of Arizona, California and Nevada, the word or words mean what the Supreme Court decision said as cited above. The use of the words does not imply an absolute amount of water but rather a limitation of use subject at all times to the availability of water. "With the active storage capacity available to the Upper Basin, including reservoirs of the Upper Colorado River Storage Project now operating or under construction, beneficial consumptive use (depletion at Lee Ferry) in the Upper Colorado River Basin, including reservoir evaporation, is limited to 6.3 million af (maf) per annum, because of the required delivery in successive 10-year periods of 75 maf in accordance with the terms of the Compact. The net depletion, excluding reservoir evaporation, would be 5.6 maf. "If deliveries at Lee Ferry were greater than 7.5 maf per year 31 |