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The following tables then compare these 1948 Compact entitlements with the middle scenario for existing and pro- jected deletions which has been compiled by the Colorado Department of Natural Resources (DNR) for its "Draft 13(a) Assessment of Upper Basin Water Availability," Tables 3.1, 4.2, and 5.3. (Attached as Appendix 1.) This depletion data supposedly represents all existing water projects on each Colorado River tributary in each Upper Basin state, and those projects which each state desires and expects to develop by the year 2000 on each Colorado tributary. The study subunit numbers used in the Colorado DNR study for each tributary in each Upper Basin state are shown on the following tables for quick reference. These study subunits are also graphically shown on Figure 2. The tables show that under these assumptions the 1948 Compact entitlements for Colorado and Utah are enough to meet the needs of each Colorado River tributary in these states, but only by a very small margin. The margin for Wyoming is more comfortable. New Mexico's entitlement is a bit short. In all cases the Colorado DNR middle depletion scenario for the year 2000 roughly corresponds to each state's 1948 Compact entitlement. This depletion scenario therefore ser- ves as a rough benchmark of when compact decisions must be made under these assumptions. Quite simply, if these deple- tion levels are exceeded on anyone tributary, there must be a corresponding curtailment of water development expectations on another tributary in the same state, if that state is to stay within its state-wide entitlement. Or, the state-wide compact entitlement of another Upper Basin state must be cur- tailed, if the Upper Basin is to meet its obligations to the Lower Basin. The use of the Colorado DNR middle depletion scenario for each Colorado River tributary as a compact benchmark may be slightly optimistic because the Colorado DNR depletion data does not include mainstem reservoir evaporation. Accordingly, the following tables attempt to account for this loss as follows: In 1975, .607 MAF evaporated from Flaming Gorge, Blue Mesa, Morrow Point and Lake Powell Reservoirs. ("Consumptive Uses and Losses Report." ) The evaporation ~. loss associ~ted with the Colorado DNR middle depletion sce- nario could be somewhat less because increased, off-reservoir depletions by the year 2000 could reduce reservoir inflows and surface areas. The tables therefore reflect mainstem reservoir evaporation charges which are 10% less than the 1975 level or .546 MAP. This adjusted evaporation charge is then allocated to each Upper Basin state according to 1948 Compact percentage entitlements, and to each Colorado River tributary within each state according to the Colorado DNR's middle depletion scenario. -24-