Laserfiche WebLink
<br />. ". . , <br />~ . <br />. . <br />. .' <br /> <br />I <br /> <br />II <br /> <br />tt <br />, <br />. <br />. <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />3.4 DATA COLLECTION AND srORAGE <br /> <br />Data coUected in the field were recorded on a standardized data sheeL Data forms used and a list of field <br />codes are presented in Appendix A The data were stored in the database management system dBase IV 1.11101. <br /> <br />4.0 RIVER HYDROLOGY <br /> <br />Row of the Green River through the study area was principally determined by releases from Raming Gorge <br />Dam and tributary input from the Yampa River. Wintertime release volwnes from Ranting Gorge Dam are <br />determined by water availability, storage and delivery, while daily nUCluations are determined by power <br />generation. The presence of the dam has had a significant effect on the yearly hydrograph by reducing spring <br />peaks and increasing fall and winter news. This section provides an overview of tbe bydrograph during the <br />first year of this inYl:StlgatJon (September 1993 . March 1994). A more detailed description of pre and post- <br />dam hydrology is Included in the SYnthesis of Winter InYl:Stll!3tiODS of Endan2ered Ash in the Green River <br />below Raminl! Gor2e Dam (Flaming Gorge Resean:h Study *18-11). <br /> <br />4.1 MONTHLY FLOWS FROM FLAMING GORGE DAM <br /> <br />During the winter of 1993.94 (December through February), average monthly releases from the Raming Gorge <br />Dam were 2,050 as with the highest average now of 2370 as in December decreasing to a low of 1780 as in <br />February (Table 3). <br /> <br />Table 3. SIUlUDIU7 of average lDOnlbl1 releases (ds) from F'1amIq Gorge Dam ror December 1993 <br />througll February 1994. <br /> <br />MONTH MINIMUM MAXIMUM AVERAGE (s.D.)' <br /> <br />. DECEMBER 1993 <br /> <br />JANUARY 1994 <br /> <br />FEBRUARY 1994 <br /> <br />2020 <br /> <br />1640 <br /> <br />1550 <br /> <br />2810 <br /> <br />2JOO <br /> <br />2100 <br /> <br />2370 (175) <br />1960 (208) <br />1780 (128) <br /> <br />'. S.D. = srandanl deviation or daily releases Cor month <br /> <br />4.2 DAlLY FLOW FLUcnJAnONS FROM FUMING GORGE DAM <br /> <br />Power generation from Flaming Gorge Dam can create substantial daily nucruaoollS in nO\V. Daily releases <br />can range from a millimwn or 800 d!I to a maximum of 4,700 d's. Maximum po.t.Ciplant releases are <br />constrained by generalDr capacity uu1 reservoir capacity. Minimum now releases baV'e been established by <br />UDWR to pCOYtdc ncccsaIy news for the tailwater aoutlisbery. During typical power generation. lowest <br />releases are early morning (1:00 - S:OO am), increasing abruptly around 6:00 am and again around 6:00 pm with <br />highest news occurring approxinlatcly 8..00 pm. However daily nUCluation patterns can vuy greatly due to <br />weekends, holidays or changing power needs. <br /> <br />Daily now nUCluatioDS were near maximum in January and February. 1994. Average claiIy Duauations <br />(minimum-to maximum) in January were approximalCly 1,00:> cis to 3.500 d's. Ayerage daily lows in February <br />were near 800 with hig!ls at approximarcly 3,00:> d's. Figure 2 illustrates representative average uu1 extreme <br />hourly releases from F\aming Gorge Dam lor January and February of 1994. <br /> <br />5 <br />