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The amount of water reserved for water development by an upside-down instream flow water right is shown at the top of the hydro graph in Figure 4 and at the bottom in Figure 5. 8000 7000 6000 """' r2 5000 u ~ Upside-down J nstream Flow ___ Water Right ~ c2 4000 E <~ 3000 Vl 1000 Water Development Potential 2000 o Oct Nov Dee Jan Feb Mar Apr May JUll Jul Aug Sep FIGURE 5. Water Development Reserved by an Upside-down Instream Flow Water Right Ideally, specifying the amounts of an upside-down instream flow water right would begin by considering a river's natural flow regime and examining the critical thresholds within the various characteristics (flow frequency, magnitude, timing, duration, and rate of change) of the flow regime. Then, through modeling and experimentation, an increment of water development that does not demonstrably impair the river's ability to perform its ecological services, is set aside. The remaining streamflow is defined as the amount of the upside-down instream flow water right. The quantification of such an instream flow water right would be expressed as "all remaining unappropriated flows of a stream except for" a specified amount for water development. The appropriation date for such a water right would be the date on which the increment of future water development was specified, and would be junior to all previously appropriated and decreed water rights. Potentially, the amount of water reserved for development by an upside-down instream flow water right could take all bfthe remaining low flows at a particular time, causing substantial ecological damage. This risk can be managed by combining conventional and upside-down instream flow water rights: the amount of water for development can then be sandwiched between a conventional instream flow water right protecting base flows and an upside-down instream flow right protecting a dynamic range of high flows. Figure 6 illustrates this combination. 8