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TABLE 4 Footnotes "Explanation of Columns" A. River basin name, row description. B. The average annual natural flow (undepleted, unregulated flow) between 1906 and 1985 from the tributary basins as computed by the U.S. Bureau of Reclamation. C. The percent of natural flow which originates in each tributary basin. It is computed by dividing the tributary value in Column b by the state total at the bottom or end of column B. D. The maximum annual consumptive use reported by the U.S. Bureau of Reclamation in their consumptive uses and losses report between 1981 and 1985 and then adjusted up to account for maximum transmountain diversion which occurred in 1978 and more detailed information concerning M&I uses as reported by the U.S. Geological Survey in 1985. The maximum adjusted consumptive use values were used to reflect the full extent of existing development which has occurred to date. E. The lower limit of future compact development was computed by taking the percent of natural flow (column C) times the remaining undeveloped compact apportionment to reach the 3.079 million acre-foot level of compact development (3,079,125 - 2,628,700 = 450,425 acre feet). This distributes the remaining compact apportionment on the basis of the percentage of natural flow originating in each the seven subbasin. This seemed equitable to the Workgroup and in cases like the Yaznpa seemed to be adequate to allow for most foreseeable development over the next 40-years or so. This also provided results which were fairly consistent with the results of the Yampa Feasibility Study currently being performed by Hydrosphere for the Colorado River Water Conservation District and the CWCB. The state total of column (D) plus column (E) is 3,079,125 acre feet or Colorado's lower limit of compact development. F. The upper limit of future development was computed to allow for flexibility and the most optimistic projection of future compact development (3.855 maf). The upper limit was computed by allowing for one-half of the remaining compact apportionment to reach the 3.079 maf level of compact development (225,213 acre feet) to occur in each basin except wherein so doing would exceed the available water supply of the basin (note: this only occurred on the Little Snake and would not have occurred here either had we considered all the flow passing the Lily gauge approximately half of which originates in Wyoming). Doing this also allowed for the uncertainty in assumptions made conceming the "Law of the River" by providing for the total consumptive use of water to reach 3.855 million acre feet. The "State Subtotals" of columns (D) plus (F) in this case total 3,843,975 acre feet or approximately 3.855 maf without including CRSP evaporation. The values in this case could be adjusted to total exactly 3.855 maf if desired, but the Workgroup elected not to do so. G. The lower limit of total consumption reflects the maximum adjusted depletions in each basin to date plus the full utilization of projects already in-place as reflected on Colorado's current "depletion schedule." The current depletion schedule was used as a check on the potential validity of the values used. However, in no case was the value in column G permitted to be less than the total of columns D plus E. For the Colorado Mainstem, Dolores and San Juan Basins, the values used actually exceed the sum of column (D) plus (E) by 91,726; 10,813; and 10,148 acre feet respectively or 112,687 of overall in order to reflect the full utilization of projects already in-place. By doing this we assure that we did not compromise any existing major projects and yet still provide for Colorado's full use of its compact entitlement in an equitable manner. H. The upper limit of total consumption was computed by adding the present day consumption (column D) to the upper limit of future development (column F). The only restriction was that column H had to be greater than or equal to the lower limit (column G). For the Colorado Mainstem, it was necessary to raise the upper limit 16,787 of in order to make it equal to the lower limit Thus, column H subtotals slightly exceed 3.855 MAF even before CRSP evaporation is added in. I&K. Given these values you can now compute the upper and lower limits of an instream flow appropriation. The upper limit is computed by subtracting column G from column B. This also becomes column K in the table and represents the total recovery instream appropriation. Please note this level of recovery instream flow does not contain any water that would be used to reach full compact development at approximately at 3.079 MAF level of development. However, it does include the utilization of 341,000 acre feet which would be lost to evaporation off the primary CRSPA storage units (Lake Powell, Flaming Gorge and Aspinall) and chazged to Colorado's apportionment. J&L. The lower limit instream flow appropriation is computed by subtracting column H from column B. This becomes column L in the table and represents one possible level of appropriation of pazagraph 3 water. In this case it represents the volume of water which must leave Colorado on average at full compact development in the basin. The value also includes the 341,000 acre feet which would go to meet Colorado's portion of CRSP evaporation, which because it is not used in Colorado can be added to the instream flow appropriation. M. Column M is the difference between columns I and J or alternatively, the difference between column K and column L. This represents one possible level of paragraph 4 water and can be described as the water that takes you from 3.079 MAF of development to at least 3.855 MAF with a little cushion (346,388 AF).