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~'r ~ ~~~~r, ~~ <br />5 ~~ I _~,,.~ ~ a <br />section 7 consultations. Depletions from projects which were constructed <br />_ ,- _ after 1975 and which are not in the section 7 baseline are not represented in <br />!~ all years of the period of record. For example, depletions resulting from a <br />-~ ~~ ,r project constructed in 1979 which did not undergo section 7 consultation would <br />-~- not be accounted for in the baseline flows calculated for 1975 through 1979. <br />' The quantity etions has not been determined or estimated; <br />~~'-~ however, the ureau believes that the make-up flows calculated for the Project <br />would change ve fat all, if these depletions were represented in <br />the entire period of recor p~ ~ g~~ ~,~.~f,L,;s ; ~--t~,us~c~rSL <br />In the hydrologic analysis, replacement reservoir releases to replace Ute <br />Water's out-of-priority diversions during a "Cameo call" were subtracted from <br />Ute Water's total diversions in calculating Ute Water's net flow reductions <br />and net depletions. <br />The flow reduction results of the hydrologic modelling are presented in the <br />Biological Assessment, Appendix 6, Attachments E and F. <br />In evaluating the impacts from the Project's reduction of flows, one can <br />compare monthly baseline flows to monthly post-Project flows where the monthly <br />flows are calculated as averages for the entire period of record (e.g., <br />Biological Assessment, Appendix B, Attachment E.6, page 7 of 8, middle table). <br />However, monthly flows averaged over the entire period of record cannot be <br />compared to the Service's flow recommendations because the recommended flows <br />vary according to the winter snowpack occurring in each year. <br />For a better evaluation, one can classify each year of the period of record as <br />one of the Service's four flow groups and calculate monthly flows as averages <br />for each flow group; the Post-project average monthly flows for each flow <br />group can then be compared to the Service's flow recommendations for each flow <br />group (e.g., Biological Assessment, Appendix B, Attachment E.6, page 7--last <br />table, page 8--all three tables). This type of comparison, however, will not. <br />reveal the extent of impacts from flow reductions because average monthly <br />values will hide large flow reduction impacts occurring in individual months. <br />To determine the magnitude, season, and type of water year for the most <br />significant impacts, one must look at the flow reduction impacts individually <br />for each month of each year in the period of record. <br />The Project's maximum monthly flow reduction does not cause the most <br />significant impact. The Project's maximum monthly (cfs) flow reduction for <br />the year 2045 level of development occurs in April, 1978, when the baseline <br />flow of 2,323 cfs is reduced by 65.8 cfs to 2,257 cfs (Biological Assessment, <br />Appendix B, Attachment E.6, page 2 of 8, top table). Because the recommended <br />flow is 2,260 cfs for this month, the make-up flow is only 2.9 cfs or less <br />than 0.13 percent of the recommended flow. <br />Also, the Project's reduction of flows from baseline flows above recommended <br />levels to post-Project flows below recommended levels does not represent the <br />Project's most significant impacts. For the 2045 level of development, the <br />Project causes fTow~ hang~m above recommended levels to below <br />recommended levels in o ly four months out of 228 months in the period of <br />record. And the maxi m of these flow reductions is to a flow of 1,606 cfs <br />s~w /' <br />