Scope of Lower Colorado River Basin Plan

Document: Attachment 1, Scope of Lower Colorado River Basin Plan, March 1965, page 6the demands that will be put upon it. New Mexico, for instance, is "under the gun" right now and Utah is facing decisions now that depend upon the availability of water in the future. The Colorado River Compact of 1922 allocated to the Upper Basin the annual consumptive use of 7.5 million acre-feet. However, the compact also obligates the Upper Basin not to deplete the flow of the river at Lee Ferry below an average annual flow of 7.5 million acre-feet. The effect of the latter provision is to make it impossible for Upper Basin uses to reach an annual assured level of greater than 6.6 million acre-feet. Present and committed uses in the Upper Basin total about 4.8 million acre-feet per year. It was assumed by the Bureau of Reclamation in preparation of the report on the Pacific Southwest Water Plan that Upper Basin uses will not expand by 2030 beyond a total of 5.85 million acre-feet with a residual average flow of 8.25 million acre-feet at Lee Ferry. This would permit the Lower Basin a corresponding use of 6,300,000 acre-feet in addition to the 1,500,000 acre-feet delivered to Mexico under the 1944 water treaty. These estimates reflect a slowdown in the rate of development of new water uses in 6Epson Perfection 4870 Photo, 400 dpi, 8 bit, 1,600,504 byte