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OOlJ7U2 Steve Schmitzer's Comments This more realistic expectation of reservoir operations must be accurately reflected in the report. Since proj ect operators will only release water once they are sure the reservoirs will fill, it is critical to draw a distention between the umeliable water source that could be provided by existing reservoirs and the highly reliable water sources provided by options like Webster Hill Reservoir and new tributary storage. Denver would like the opportunity to review and comment on draft language for this conclusion to assure this type of realistic expectation is included in the final report. This will be considered while drafting the Executive Committee Recommendation. Other operating consequences are as follows: 10 To make CFOP releases, the probability of filling the reservoirs must be high. For example, under current demands for Denver in the CROS program, the probability of filling the reservoirs must be at least 90% after the releases are made. As demand increases and approaches existing supply, operators such as Denver may require more than a 90% fill probability. Why 90%? It is beyond the scope of the study to predict a fill. 2. The possible impacts on the trout fisheries (eog., below Williams Fork Reservoir), which are an important issue, would need to be considered. Beyond scope. 3, The impact ofthis option on power generation at Williams Fork Reservoir, Dillon Reservoir, and the East Portal should at least be mentioned, ifnot quantified. Noted. Our scope specified only looking at GMR, Ruedi and Shoshone power generation. Williams Fork Reservoir On page 32 it is stated that "Williams Fork Reservoir is not a direct water supply for Denver." This is inadequate reasoning. Williams Fork Reservoir is a direct supply in the sense that it enables diversion of significant amounts of municipal water supply at numerous locations that otherwise would not be directly diverted. Noted. II On page 33, the text for the results of Alternative Ie, Denver Water System Operations, should state that under this operation, Williams Fork Reservoir does not fill in 1975, 1980, 1982; and there is a 19,000 afdeficit in 19780 As stated previously, in a year such as 1978,20,000 affor flows in the IS-Mile Reach are required, but Williams Fork has not refilled from the severe dry year of 1977. Until the reservoirs completely refill, the reservoir operators have no way of knowing when the critical drought period is over. Water would not be released in a year such as 1978, unless there is some kind of payback "insurance" from another reservoir or a reduction in the river calls. As described in a January 22, 2002 letter to you, CROS releases from Williams Fork would occur in four of the eight designated years under existing levels of demand and releases would be less and may approach zero as demand on Denver's existing system approaches that system's capabilities to supply water. After CROS releases are made, even less water would be available for CFOPS. We believe that CFOPS will supersede CROS releases. Also on page 33, the report states that Williams Fork Reservoir refilled eventually and was never completely drawn down. First, don't all reservoirs eventually refill? If so, what is the point of this statement? Noted. Secondly, it should be clearly explained that in STATEMOD Williams Fork Reservoir was never completely drawn down because (1) only existing demands are modeled, we did model future demands (2) the model doesn't include the mid-1950's critical P:\Data\GEN\CWCB\19665\Report Phase 2\Technical Memorandum No. 12\Appendix B.doc 10