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<br />recommendations within range results in a 0,8 cfs recommendation, Averaging the two winter <br />flow recommendations within range results in a 0.35 cfs recornmendation. <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 San Luis Creek near Poncha Pass, CO (ID #08224110), which has a <br />drainage area of 6,6 square miles (See Gage Summary in Appendix C), The total drainage area <br />of the Dorsey Creek Drainage is approximately 2,8 square miles, The period of record for this <br />gage was 1979 to 1985, the period of record used by staff in their analysis was 1979 - 1985, or 6 <br />years of record. Table 2 below displays the flow of Dorsey Creek at the gage, in terms of a <br />percentage of exceedence. <br /> <br />Table 2: Estimated Stream Flow in Dorsey Creek <br />Exceedences Janoa Februa March 01 M. June ", Au ust 5e tember October November December <br />1% 0.43 0.51 0.64 1.116 3.25 2.09 0.92 1.28 0.64 0.87 1.00 0.81 <br />5% 0.43 0.47 0.110 1.36 2.64 1.47 0.72 0.60 0.45 0.55 0.72 0.17 <br />10% 0.41 0.47 0.110 1.15 2.32 1.32 0.60 0.47 0.40 0.51 0.68 0.72 <br />20% 0.38 0.39 0.51 0.85 2.05 1.11 0.55 0.41 0.31 0.47 0.60 0.51 <br />50% 0.32 0.34 0.38 0.64 1.02 0110 0." 0.29 0.23 0.28 0.43 0." <br />60% 0.21 0.26 0." 0.41 0.60 0.23 0.15 0.17 0.15 0.21 0.30 028 <br />90% 0.17 0.21 0.30 0.34 0.43 0,19 0.10 0.13 0.11 0.14 0.26 0.25 <br />95% 0.16 0.21 0.30 0.29 0.38 0,17 0,08 0.09 0.09 0.12 0.24 0.23 <br />99% 0.15 0.17 0.27 0.28 0.30 01. 0,06 0.04 0.06 0,08 0.21 0.19 <br /> <br />Dorsey Creek Estimated Stream Flow <br /> <br />1.4 <br /> <br />1.2 <br /> <br />1 <br /> <br /> <br />J!! 0.8 <br />u <br /> <br />0.6 <br />0.4 <br /> <br />0,2 <br />o <br /> <br />- . <br /> <br />JAN <br /> <br />FEB <br /> <br />MAR <br /> <br />APR <br /> <br />MAY <br /> <br />JUN <br /> <br />JUL <br /> <br />AUG <br /> <br />SEP <br /> <br />OCT <br /> <br />NOV <br /> <br />Dee <br /> <br />Month <br /> <br />Table 2 shows that the summer flow recommendation of 0,8 cfs is available at least 50% of the <br />time for the month of May, The winter flow recommendation of 0.35 cfs is available at least <br />50% of the time from (6/1 ~ 7/14 and 11/1 ~ 4/30), The winter recommendation was further <br />reduced to 0,25 cfs for the time period of July 15th through October 31st based on limited water <br />availability. <br /> <br />-4- <br />