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I I . DD:1590 Description of ExislIng Model 3 Table 7 lists th.: overall rankings assigned to the V'..trious water rights and \Vater rights groups represemed in the model. OPERATIONS OF EXlSTING FACIUTIES The operating procedures of major existmg or soon-lo-be-developed water supply facilities are represented in the basin model. Specific facilities and systems modeled in detail include the Wayne N. Aspinall Unit (formerly known as the Curecanti Unit), the Uncompahgre Project, the Bostwick Park Pro- ject. the Dallas Creek Project, and the Project 7 Water Authori[}'. Smaller municipal and domestic sys- tems, such as the City of Gunnison and the Town of Crested Bune, were modeled simply as depletions because of their small size and the spatial and temporal proximity of diversion and return flow poinLS. The modeled operating procedures for the major systems are described briefly below. AspioaII Unir Aspinall operations are represented only by Blue Mesa storage and release policies; Morrow POlnt and Crystal reservoirs are assumed to operate, from a monthly perspective, as run-of-river facilities with no storage capadly (and. consequently. nQ evapontion). Blue Mesa. releases in January through July are detenruned by inflow forecasts and releases in August through December are determmed from a set of declining storage targets. Both these releases are subject to a minimum power release require. mem which is a function of reservoir contents. After these operations are executed, the model checks to see if a minimum flow of )00 cfs has been achieved in the mack Canyon; if this flow has not been achieved, an additional release is made to bring the minimum up to 300 cfs. The objective of determining releases from forecasts is to obtain as constant 3 flow regime be. low Crystal Dam as possible while filling Blue Mesa without a spill by the end of July. The forecast-based release for the current month is computed using the following cqu3110n: release:;:::. I (forecast + sideinflow - contents - capacity)jmomhsleft) - inflow forecast is the projected inflow from the current date through July sideintlow is the average inflow between Blue Mesa and Crystal for the current month contents is the aClive contents of Blue Mesa at the beginning of the current month capacity is the active capacity of Il\ue Mesa (829.600 acre-feet) momhsleft is the number of months from the current date through July inflow is the Blue Mesa inflow for the current month The objective :)f defining releases based on declining storage targets is (0 obtain adequate winter drawdown of l3Iue Mesa to prevent ice-jam-induced flooding III (he Gunnison area and to have adequate space to store the next year's runoff. The slOrage targets were obtained from Ihe USBR Salt Lake Regional office and are staled in terms of acre-reet of active capacity. The targets used in the model are as foUows: July August September 1129.600 800.000 750.000 700.000 650.000 590.000 October N ovem ber Decem ber