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.. . account for the dynamic and unpredictable nature of basin hydrologic conditions. Operations are examined and modified monthly as hydrologic conditions change. In general, the same procedure is used for the remainder of the Upper Basin reservoirs with the exception that no downstream releases are required for Compact purposes. Using the runoff forecast, the reservoirs are drawn down in the fall and winter and allowed to fill during the spring runoff. possible changes in these operating plans are taken into account in preparing an operating plan for Lake Powell. Redistributing excess flow releases would not place a risk on the Upper Basin so long as such releases by themselves do not result in the content of Lake Mead being below that of Lake Powell on September 30 of that year, or during subsequent years, thus triggering the equalization provision of the Operating Criteria. This provision of the Operating Criteria is not expected to be invoked during this brief period of excess water if the operation of Lake Mead is carefully moni tor ed and the appropr iateness of excess releases are evaluated monthly. This is ensured if the storage in Lake Mead remains above that in Lake Powell. Similarly, it does not appear that an operation of the Upper Basin reservoirs to obtain additional benefits would adversely affect conservation storage in the Lower Basin reservoirs so long as the additional releases do not force flood control releases from Lake Mead that otherwise would not have been required. This situation would occur only when the release of excess flows from Lake Powell would raise the contents of Lake Mead into the 1.5 million acre-foot dedicated flood control space. 2.3.4 Water Use/Conservation Considerations With full reservoirs and the Basin's present and anticipated level of water needs through 1992, excess river water is likely to occur even with below normal runoff condi tions. However, for all of the Basin states' Colorado River water needs to be met during this period, the Secretary of the Interior must either formally declare a "surplus river condition" or allow the beneficial Colorado River water needs in excess of a state's basic apportionment to be met by utilizing unused apportionments of other states. presently, California is the only Basin state using or capable of using more Colorado River water than its basic apportionment. However, with the commencement of the Central Arizona project (CAP) water deliveries in December 1985, California is limited to its basic apportionment of 4.4 maf of Colorado River water per year, unless the Secretary of the -13-