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<br /> <br />Table I; Data <br /> <br />Party Date Q 250%-40% Summer (3/3) Winter (2/3)- <br />DOW 09/17/1980 45.1 112.8 - 18.0 11.1(TT 6.ilT <br />DOW 12/04/1987 19.2 47.9 -7.7 10.3 4.8(1) <br />DOW 12/04/1987 23.7 59.2 - 9.5 10.0 9.6 <br />DOW '12/04/1987 25.2 63.1 - 10.1 15.7 9.6l1T <br />DOW 03/11/1993 11.5 28.7 - 4.6 12.9 4.9 <br />DOW 03/11/1993 12.3 30.7 - 4.9 6.8 2.8l1T <br />DOW 03/11/1993 10.3 25.7 -4.1 6.8 4.2 <br /> <br />BLM = Bureau of Land Management DOW = Division of Wildlife <br />(I) 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 recommendations, which met 3 of 3 criteria and are within the accuracy range <br />of the R2CROSS model, range from 15.7 cfs to 6.8 cfs (See Table 1). The winter flow <br />recommendations, which met 2 of 3 criteria and are within the accuracy range of the R2CROSS <br />model, range from 9.6 cfs to 4.2 cfs (See Table 1). Averaging the six summer flow <br />recommendations within range, results in a 10.5 cfs recommendation. Averaging the three <br />winter flow recommendations within range, results in a 6.5 cfs recommendation. <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. Staff found one historically operated streamflow gage located <br />within this reach and approximately one mile upstream from the confluence with the South Fork <br />San Miguel River. The hydrograph was derived from data collected by the USGS stream gage <br />for the San Miguel River near Telluride, CO (ID #09171200), which has a drainage area of 42.8 <br />square miles (see below). The period of record for this gage was 1959 to 1965, the period of <br />record used by staff in their analysis was 1959 - 1965, or seven years of record. Table 2 below <br />displays the estimated flow of the San Miguel River, in terms of a percentage of exceedence. <br /> <br />Table 2: Estimated Stream Flow in San Miguel River: <br />Exceedence Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nay Dee <br />1% 18 20 50.56 104.4 404.6 468.4 416.9 205.6 92.6 48.28 33.4 23 <br />5% 17 19 30.7 90 349 415 358.4 120.7 73 39.7 29 20 <br />10% 16 19 23.4 78 238.8 360 268.8 94.2 65 38 28 19 <br />20% 16 18 20 61 184.8 310 201.2 76 56 33 26 18 <br />50% 15 15 16 35 119 232 97 51 37 27 22 17 <br />80% 14 14 14 22 70 132 55 39 27 23 20 16 <br />90% 13 14 14 16 43.6 116 44.6 33 26 22 19 16 <br />95% 13 14 14 16 36.3 100 40.3 29 25 22 19 13 <br />99% 13 14 12 15.8 29 80.6 32.72 27 24 21 18 13 <br /> <br />-4- <br /> <br />