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<br />. <br /> <br />. <br /> <br />. <br /> <br />three hydraulic parameters at adequate levels across riffle habitat types, aquatic habitat in pools <br />and runs will also be maintained for most life stages of fish and aquatic invertebrates (Nehring <br />1979; Espegren 1996). <br /> <br />For this segment of stream, three data sets were collected with the results shown in Table 1 <br />below. Table 1 shows who collected the data (Party), the date the data was collected (Date), the <br />measured discharge at the time of the survey (Q), the accuracy range of the predicted flows <br />based on Manning Equation (240% and 40% of Q), the summer flow recommendation based on <br />meeting 3 of 3 hydraulic criteria and the winter flow recommendation based upon 2 of 3 <br />hydraulic criteria. <br /> <br />Table 1: Data <br /> <br />Party Date Q 250%-40% Summer (3/3) Winter (2/3) <br />BLM/CDOW 7/18/95 6.45 16.1 - 2.6 6.6 2.3t1) <br />BLM 6/29100 1.03 2.6 - 0.4 6.4(1) 1.3 <br />BLM 6/29100 1.04 2.6 - 0.4 11.0(1) 1.7 <br /> <br />BLM = Bureau of Land Management DOW = Division of Wildlife <br />(1) Predicted flow outside of the accuracy range of Manning's Equation. ? = Criteria never met in R2CROSS Staging Table. <br /> <br />Biologic Flow Recommendation <br />The summer flow recommendation, which meets 3 of 3 criteria and is within the accuracy range <br />of the R2CROSS model is 6.6 cfs (See Table 1). The winter flow recommendations which met 2 <br />of 3 criteria and are within the accuracy range of the R2CROSS model fall between 1.7 and 1.3 <br />cfs (See Table 1 ). Averaging the two winter flow recommendations gives a winter <br />recommendation of 1.5 cfs. <br /> <br />Hydrologic Data <br /> <br />After receiving the cooperating agency's 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 hydro graph below was derived from data collected by the <br />USGS stream gage for Roc Creek near Uranium, CO (ID #09179000), which has a drainage area <br />of 75.8 square miles (See Gage Summary in Appendix C). The period of record for this gage <br />was 1944 to 1952, the period of record used by staff in their analysis was 1944 - 1952, or eight <br />years of record. This gage is located in the lower third of the proposed segment. Table 2 below <br />displays the estimated flow of Roc Creek, 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 /> <br />Table 2: <br /> <br />Roc Creek Stream Flow <br />Exceedenoes <br />1% <br />5% <br />10% <br />20% <br />50% <br />80% <br />90% <br />95% <br />99% <br /> <br />Januarv Februarv March Anril Mav June Julv Auoust Seotember October November December <br />7.30 11.74 20.52 220.40 187.10 112.80 22.52 15.68 4.56 8.40 7.20 8.26 <br />7.00 8.14 12.00 167.00 106.60 74.00 15.20 7.60 3.50 7.00 6.40 6.20 <br />7.00 7.00 10.00 127.00 86.60 49.00 10.20 3.81 2.30 5.44 6.00 5.20 <br />5.40 5.30 9.48 59.00 64.40 24.00 4.70 2.20 1.70 3.40 5.40 4.50 <br />4.00 5.00 6.50 17.00 26.00 7.20 1.50 1.50 1.30 1.70 2.80 3.30 <br />2.56 3.20 4.00 11.00 7.70 2.40 0.70 0.60 0.80 1.30 1.20 0.70 <br />0.80 2.60 3.40 6.90 4,22 1.30 0.50 0.40 0.50 1.00 0.70 0.10 <br />0.80 2.40 2.28 4.80 3.40 0.60 0.40 0.30 0.50 0.90 0.40 0,00 <br />0.80 2.30 1,80 3,00 2.20 0.50 0.30 0.20 0.30 0.80 0.14 0,00 <br /> <br />- 4- <br />