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Horsefly Creek at the confluence with the San Miguel River is approximately 110.0 square miles, so higher flows would be expected at the mouth of the creek than at the gage location. The period of record for this gage was 1942-1951, the period of record used by staff in their analysis was 1942-1951, or 10 years of record. Table 2 below displays the stream flow of Horsefly Creek, in terms of a percentage of exceedence. Table 2: Estimated Stream Flow on Horsefly Creek Exceedences Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nay Dee 1% 3.8 7.6 30.6 1282.01661.7 354.5 9.8 35.8 18.4 13.9 14.9 2.7 5% 3.8 7.6 30.6 754.5 644.8 55.4 4.6 3.8 1.3 7.7 9.6 2.7 10% 3.8 7.6 30.6 473.7 454.6 32.9 3.4 2.3 0.8 2.7 9.6 2.3 20% 1.1 1.5 22.9 343.8 223.1 19.9 2.0 0.8 0.0 1.9 1.9 1.5 50% 0.4 1.1 2.3 133.7 61.1 7.6 0.4 0.0 0.0 0.4 1.1 0.8 80% 0.0 0.4 1.1 9.9 26.0 0.4 0.0 0.0 0.0 0.0 0.8 0.4 90% 0.0 0.4 0.8 5.7 13.8 0.0 0.0 0.0 0.0 0.0 0.4 0.0 95% 0.0 0.0 0.8 4.8 9.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 99% 0.0 0.0 0.8 2.7 1.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Estimated Stream Flow on Horsefly Creek 20 15 -- .l!! 10 <.l o 5 Jan Feb Mar Apr May Jun Jul Aug Sep Oet Nov Dee Month Table 2 shows that the summer flow recommendation of 13.0 cfs is available only from April 1 to June 5, which corresponds with the snowmelt runoff period. Accordingly, the BLM recommended that 13.0 cfs be appropriated during April 1 to June 5, and that no appropriation be made for the remainder of the year because of limited water availability. Precipitation Data Staff reviewed local precipitation data sets from one site located around the Cottonwood Creek Drainage (see Precipitation Data in Appendix C). Table 3 shows the water year and the percent of average precipitation recorded for this site. It is staffs opinion that the ten years of stream- flow data analyzed is representative of slightly below average water-years. - 4-