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I I I I I I I I I I I I I I I I I I I 9 until a Record of Decision is made on the Glen Canyon Environmental Impact. Statement (GCEIS) some time in 1994. The interim flow restrictions are as follows: Parameter Maximum Flow Minimum Flow Ramp Rates , Ascending Descending Daily Fluctuations , 20,000 CfSI 5,000 cfs - nighttime 8,000 cfs - 7 a.m to 7 p.m 8,000 cfs per 4 hours2 1,500 cfs per hour 5,000/6,000/8,000 cfs3 These flow restrictions are being monitored to observe their effects on downstream resources. Because the level of Lake Powell has dropped considerably since 1987, the risk of releases greater than powerp1ant capacity during water year 1992 is negligible. Lake Mead Lake Mead pumping and releases during calendar year 1993 will be allowed, sufficient to satisfy up to 7.5 MAP of beneficial consumptive use in the Lower Division States, treaty requirements with Mexico, conveyance losses, and river and reservoir regulation requirements. The outlook for lowest and highest monthly releases for 1993 will be 500,000 AF and 1.05 MAF, respectively. Lake Mead is expected to finish calendar year 1992 at 19.2 MAF, which is 74 percent of capacity and approximately 47 feet from its full capacity of 25,877,000 AF. Reservoir storage elevation is projected to rise to 1,176 feet in February 1993, which is 19.7 MAF or 75 percent of capacity and approximately 43 feet from full capacity. Storage elevation is lto be evaluated and potentially increased as necessary in years when delivery to the Lower Basin exceeds 8.23 MAP 2r\ot to exceed 2,500 cfs per hour 3daily fluctuations limited to 5,000 cfs for monthly release volumes less than 600,000 acre-feet, 6,000 cfs for monthly release volumes of 600,000 to 800,000 acre-feet and 8,000 cfs for monthly volumes over 800,000 acre-feet