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• above average pr ecipitetion have shorn four to eight inches of additional precipitation. <br />From the date it appears the lest 16 years have been somewhat ratter then normal. <br />sage Creek. The following discussions Yill progress on each drainage from the uppermost <br />monitor to the furthest downstream site. Site YSSF3 ie located upstream of the Toast Mine <br />in Section 30, Range 87W on Sege Creek (see Exhibit 7-1). The flume site was established <br />in 9/90 and both instantaneous end continuous flow measurements have been collected et <br />this monitor. Continuous flow monitoring was inf t(ated on 05/17/91. Flow in this channel <br />reach has exhibited both intermittent end perennial characteristics, depending on snowfall <br />end rai of ell variability between years. Zero flow was documented in both September and <br />October, 1990. The flaw has been perennial from 1991 through 3/94. <br />From a review of the flOY hydrographs (Appendix 7-6), the period of snowmelt influence <br />appears to start in the end of March or early April and tests into May end early June. <br />The largest peak flows occur in the spring during the snormelt influenced runoff period <br />end range from <1.0 to 7.2 cfs. A tabulation of the seasonal flow statistics shows mean <br />flow rates in the spring ere 0.7 cfs, while summer and fall mean flows (dominated by <br />• bas efloY) are 0.04 cfs. Summer and fell rainfall runoff peaks at Site YSSF3 ere very <br />smell (<0.5 cfs) end of little significance. In terms of flow volumes (see mean daily <br />flow tables in Appendix 7-6), measured spring flow volumes ere 10 to 50 times as great es <br />summer flow volumes. Gaps in the c6ntinuous flow record at this site ere due to proximate <br />beaver dams, freezing within [he stilling welt, and low flows (<0.020 cfs) that ere below <br />the detection limit of the stilling well communication line to the flume. <br />Site Y552 is located approximately 6800 feet downstream from Site YSSF3 in Section 18, <br />R87Y. This site was originally monitored by the USGS (1981 to 1983) with a Parshall <br />flume. Thus, a second site 1D (YSSF1) is used to reference the continuous flow monitoring <br />data. PYCC reestablished monitoring at this site and has colleeted instantaneous floY <br />date since 5/91. Flow in this channel reach has exhibited both intermittent end perennial <br />characteristics. Intermittent flow (zero flows in 1981 and 1982) has been documented (see <br />Appendix 7-6) during two of the six years this site has been monitored. <br /> From a review of the flow hydrographs, the period of snormelt influence appears to start <br /> in early April and lasts into early end mid•June. The largest peak flows occur in [he <br />• spring during the snowmelt influenced runoff period and range from 1.5 to 15 cfs. A <br /> tabulation of the seasonal floe statistics shows mean flow rates in the spring are 2.3 <br /> cfs, chile summer and fall mean flows are 0.15 end 0.03 cfs, respectively. Summer end <br /> 97 <br />