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01n183 26 A total of 26 demands have been represented in the Yampa Basin model to represent the 1989. maximum demand scenario. These demands, which are listed in Table 4-5 as demand numbers 1 through 261 represent municipal, industrial, agricultural, recreational "and trans-basin exPOrt wJ.ter uses. It is important to remember that these demands are in fact increments to move from the historical demand condition, which is embedded in the gage hydrology used ill (he model, 10 the 1989 maximum demand condition. Total depletions representing 1989 maximum conditions are 121,174 af. Three additional demands represented in the model and operational for the 1989 demand .condition are demands 34, 37 and 38. Demand 37 is the portion of currelll Steamboat Springs municipal demand that could not have been met historically through ihe City's Fish Creek delivery system. This water would historically have had to have been pumped directly from the Yampa River. Demand 34 represents increased irrigation watcr use in thc upper Yampa basin above Stagecoach Reservoir occurring as a resuil of the Yamcolo . Stagecoach exchange. This demand totals 4000 af per year and is modeled as approximately 25 percent eonsumptive. Demand 38 is the historical Maybell Canal diversions. Diversion records were obtained from the Division 6 office of the State Engineer. This demand is represented as a withdrawal rather than as a depletion because it was considered important to represent its effect as the sedor downstream water right in the basin. It should be noted that in several instances demands that occur on tributaries to the Yampa River have been placed directly on the mainstem. This was done in order to avoid synthesizing stream flows on the many small triputaries. Rather than individualized gains from each tributary, "reach" gains were defined that include several sources. By placing tributary demands On. the mainstem, there will be no net effect to other mainstem demands so long as these tributary demands were not historically shorted. If shortages wo'uld have occurred, the demand as represented in the model will be satisfied by water from the mainstem, a physical impossibility, However, because these shortages are intrcquent and of relatively small amounts and because the net effect on the Yampa Hiver mainslem is the same, this error is considered, negligible, Demands 25 - 33 in Table 4.5 represent demand increments to mow to future conditions. These demand are represented in the model as a single sel of demands whose magnitude changes depending on the demand level under evaluation. For demand level 1. (1989 maximum conditions) these demands are set equal to zero. The second arid ihird demand levels represent the growth from current to future near.term (year 2015) and long-term (year 2040i conditions. Demands 25 - 33 are assumed constant from year to year throughout the stud~ period and are given a priority lower than Juniper.Cross rights in the model. In the Yampa model, demand arcs representing future demand increments have priorities lower than the priority assigned to the T&E instream Oow arc (i.e., the priority of the Juniper Project water right) while demand arcs representing existing (1989) maximum demands have priorities higher than that of the instream Oow arc. In several scenarios, the effect of subordinating the Juniper right to the future demand increment is examined by changing the rank on the Juniper right to be junior to the future demands. ,"