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<br />Table 1: Data <br /> <br />Party Date Q 250% -40% Summer (3/3) Winter (2/3) <br />DOW 10/22/1998 4.8 12.1 - 1.9 6.8* 3.5* <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 />* Estimated Flow based on a calculated D84 value of 0.55. <br /> <br />Biologic Flow Recommendation <br />The summer flow recommendation, which met 3 of 3 criteria and is within the accuracy range of <br />the R2CROSS model is 6.8 cfs (See Table 1). The winter flow recommendation, which met 2 of <br />3 criteria and is within the accuracy range of the R2CROSS model is 3.5 cfs (See Table 1). <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 hydrograph below was derived from data collected by the <br />USGS stream gage for Smith Fork Gunnison River near Crawford, CO (ID #009128500), which <br />has a drainage area of 42.8 square miles (See Gage Summary in Appendix C). The total <br />drainage area of this segment of the North Fork of the Smith Fork Gunnison River is <br />approximately 21 square miles. The period of record for this gage was 1935 to 1994, the period <br />of record used by staff in their analysis was 1935 - 1994, or 60 years of record. Table 2 below <br />displays the estimated flow of North Fork Smith Fork Gunnison River at the gage, in terms of a <br />percentage of exceedence. <br /> <br />Table 2: Estimated Stream Flow in North Fork Smith Fork GUllllison River <br /> <br />Exceedences Jan feb mar apr may Jun jul aug sep oct nov dec <br />10/0 9.1 10.6 34.9 147.2 331.7 257.8 63.2 16.3 15.8 17.3 13.4 9.6 <br />50/0 6.2 6.7 20.2 109.7 205.6 165.4 34.1 11.3 11.0 13.0 9.1 6.7 <br />10% 4.5 5.3 15.4 85.9 172.3 132.0 27.4 9.1 9.1 9.6 7.2 5.3 <br />20% 3.9 4.5 9.1 57.6 139.7 84.5 19.7 7.2 6.7 7.2 5.8 4.4 <br />80% 2.5 2.6 3.6 11.5 44.2 24.0 6.2 3.5 2.8 3.1 3.1 2.6 <br />90% 2.3 2.4 3.1 7.7 34.6 16.8 4.6 2.7 2.3 2.7 2.8 2.4 <br />95% 2.2 2.2 2.7 6.5 25.4 12.5 3.6 2.1 1.9 2.4 2.6 2.3 <br />99% 1.8 2.0 2.4 4.2 10.8 8.0 2.5 1.2 1.4 1.9 2.2 1.9 <br /> <br />-4- <br />