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<br />, <br /> <br />< <br /> <br />e <br /> <br />e <br /> <br />e <br /> <br />, the summer flow recommendation based upon meeting 3 of 3 hydraulic criteria and the winter <br />flow recommendation based upon 2 of 3 hydraulic criteria, <br /> <br />Table 1: Data <br /> <br />Party Date Q 250%-40% Summer (3/3) Winter (213) <br />WWW/QR 11118/98 6,07 15,2 - 2.43 4 1.5(1) <br />CWCB 4/15/99 4,09 10,2 - 1.64 14,5(1) 1.om <br />CWCBIBLM/DOW 10/14/99 16,7 41.8 - 6.68 7,6 1. 6(1] <br />WWW/QR 11/17/98 6,53 16,3 - 2,61 ? o,6fTT <br />BLM 4/16/96 9,04 22,6 - 3,61 5,8 2.6fTT <br /> <br />BLM = Bureau of Land Management DOW = Division of Wildlife WWW = WW Wheeler OR = Queen of the River <br />(I) Predicted flow outside oftlie accuracy range of Manning's Equation. ? = Criteria never met in R2CROSS Staging Table. <br /> <br />Biologic Flow Recommendations <br />The BLM recommended a 6,0 cfs summer flow and a 2,5 cfs winter flow based on their April <br />16th, 1996, data collection effort. An alternative flow recommendation, based on additional data <br />collected by WWW/QR, of 4,25 cfs, May I through July 31 and 3 cfs, August 1 through April <br />30, was proposed by the City of Cripple Creek and Cripple Creek/Victor Mining Company, The <br />WWW/QR flow recommendations were based on an adjustment of the CWCB/CDOW 1 ft/sec <br />velocity criteria standard for summer flows down to 0,8 ft/sec (See WWW/QR Executive <br />Summary), The CWCB tabled action on this flow recommendation until CWCB staff could <br />review the additional data collected by WWW/QR and to collect additional data, if necessary. <br /> <br />Staff reviewed the data collected by the BLM and WWW/QR and decided to collect two <br />additional data sets, bringing the total number of data sets for review to five. The summer flow <br />recommendations which met 3 of 3 criteria and are within the accuracy range of the R2CROSS <br />model fall somewhere between 7,6 and 4,0 cfs (See Table 1), Averaging the three summer flow <br />recommendations gives a summer recommendation of 5,8 cfs, <br /> <br />The winter flow recommendations, which met 2 of 3 criteria all fall outside of the accuracy range <br />of the R2CROSS model. It is our belief that recommendations that fall outside of the accuracy <br />range of the model may underestimate the required winter flow, To determine the winter flow <br />recommendation, staff looked at valid winter flow recommendations for the stream segment <br />located above Barnard Creek (1.6 cfs) and located below High Creek (4,1 cfs) and considered the <br />winter recommendation offered by the BLM (2,5 cfs) and WWW/QR (3,0 cfs). After consulting <br />with the Colorado Division of Wildlife, staff believes 2.75 cfs will be sufficient to protect the <br />natural environment to a reasonable degree, <br /> <br />Hydrologic Data <br /> <br />After receiving the cooperating agencies' biologic recommendation, the CWCB staff conducted <br />an evaluation of the stream hydrology to determine if water was physically available for an <br />instream flow appropriation, The hydrograph was derived from data collected by the USGS <br />stream gage for Fourmile Creek below Cripple Creek (ID #07096250), which has a drainage area <br />of 272 square miles (See Gage Summary in Appendix C), The period of record for this gage is <br />1992 to present, the period ofrecord used by staff in their analysis was 1992-1997 or five years <br />of record, The estimated drainage area of Fourmile Creek upstream and including Barnard <br />Creek is 192 square miles and the drainage area upstream of High Creek is approximately 208 <br />square miles, Tables 2 and 3 below display the estimated flow of Fourmile Creek at the <br />confluence with Barnard and High Creeks, in terms of a percentage of exceedence, The orange <br />shading highlights how often the summer flow has been available and the blue shading highlights <br />how often the winter flow has been available, <br />