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5 <br />subsection to the extent that the Secretary, after consultation with the Upper Colorado <br />River Commission and representatives of the three Lower Division States and taking <br />into consideration all relevant factors (including, but not limited to, historic stream- <br />flows, the most critical period of record, and probabilities of water supply), shall find <br />this to be reasonably necessary to assure deliveries under clauses (1) and (2) without <br />impairment of annual consumptive uses in the upper basin pursuant to the Colorado <br />River Compact: Provided, That water not so required to be stored shall be released <br />from Lake Powell: (i) to the extent it can be reasonably applied in the States of the <br />Lower Division to the uses specified in article III(e) of the Colorado River Compact, <br />but no such releases shall be made when the active storage in Lake Powell is less than <br />the active storage in Lake Mead, (ii) to maintain, as nearly as practicable, active storage <br />in Lake Mead equal to the active storage in Lake Powell, and (iii) to avoid anticipated <br />spills from Lake Powell." <br /> <br />The Secretary promulgated the required operating criteria in 1970, which set a "minimum <br />objective release" of 8.23 MAF per year from Lake Powell. <br /> <br />VI. Hydrology <br /> <br />A. Supply. The Colorado River Compact was negotiated after several decades of <br />abnormally high flows on the River such that it likely overestimated the long-term <br />supply of the Colorado River Basin. This wasn't immediately apparent until the low <br />flow years of the 1930s and 1950s. [See chart] Current average virgin flow at Lee <br />Ferry is around 14.8 MAF. The past five years have been ones of extraordinary <br />drought. The 2000 inflow to Lake Powell was 61% of average; 2001 was 59%. The <br />2002 inflow was 25% of average, the lowest ever recorded since Lake Powell began <br />filling in 1963. 2003 and 2004 inflow were both at 51% of average. Snowpack in the <br />basin above Lake Powell is currently very slightly above average. High precipitation <br />in the Lower Basin has resulted Lake Mead rising to 16.22 MAF (62.7 percent of <br />capacity), while storage in Lake Powell has dropped to 8.06 MAF (33.2 percent of <br />capacity). These figures are as of March 28, 2005. <br /> <br />B. Deliveries. Nevertheless, because of the high flow years of the mid-1990's, and the <br />Operating Criteria, for the nine-year period from 1996-2004, deliveries past Lee Ferry <br />total over 93 MAF. <br /> <br />C. Consumptive Uses. Total uses by the Upper Basin have topped out at around 4.2 <br />MAF, and decreased during the drought. Colorado's total uses are around 2.8 MAF. <br />Total uses in the Lower Basin, including reservoir evaporation and tributary uses, are <br />10-11 MAF. <br />