WSPC06577 - Laserfiche WebLink

Home Browse Search

"''''1.l!) uu,itL II SURPLUS II 3.6 SURPLUS -,\ This card defines the surplus operating strategy. 3.6.1 Preparation The strategy 10 is the amount of assurance the surplus oper- ating strategy gives in being able to anticipate and distrib- ute surplus water without having to make flood control re- leases. The amount of assurance, referred to as the assurance level, is input to the model as a probability and serves as the identification of the strategy chosen. For ex- ample, an assurance level (strategy 10) of 0.95 schedules ap- propriate surplus releases from Lakes Powell and Mead and distributes them throughout the year to assure that unscheduled releases for flood control will not be occur in approximately 95 percent of the years of operation. The strategy 10 cannot exceed 0.99. The strategy 10 Increment value allows for multiple runs to be made with different strategies. If the value is nonzero, two items on the RUN card must also be set: (1) set "the number of years to increment the hydrology" to zero or leave blank, and (2) set the number of runs to be made. The given strategy 10 will be used in the initial run, then incremented for each succeeding run by the strategy 10 Increment. The distribution of "total system" storage is the proportion of the combined Lake Mead and Lake Powell storage to be al- located to Lake Powell. This value is used by the model only in the determination of surplus releases. The 602(a) probability term is used to provide a buffer of storage in Lake Powell to assure 602(a) requirements are sat- isfied. The buffer amount of storage is equal to the differ- ence between the mean ahnual natural flow at Lees Ferry and the annual natural flow at Lees Ferry at the percentile specified as the 602(a) probability term. 3.6.2 Quantity One card is prepared. Zero will be used for fields left blank. 19