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results of the gauging stations along Trout Creek indicate that [he monitoring program is being placed on-line early enough in <br />the year to record flow prior to the peak runoff period for each year. The individual data points show the monthly average <br />flows and give some indication of [he variability between mild winters (winters of less snow accumulation) and harsh winters. <br />The graph showing 2000-2002 data indicates a decrease in the total streamflow in 2002 from 2000 and 2001 levels. The <br />1992-2002 graph suggests [hat 2002 was the dries[ winter over the past decade and 1993 was [he wettest for [he watershed. <br />The continuous recorder at TR-b was down for repairs for much of 2002; therefore, streamflow data was only recorded for [he <br />months of June and August. <br />The flow record for 2002 shows a very low peak flow [o have occurred in May as it did during 1991, 1992, 1994, <br />1996 and 2001. The runoff from the mine site was much lower in 2002 than in previous years due to less snowpack on the <br />mine site and the on-set of warmer temperatures occurring earlier in [he spring. The flow data presented in Figure I consists <br />only of information derived from continuous flow records. Instantaneous flow measurements obtained between 1989 and <br />June 1994 for this location are provided in Appendix A. Prior to that time, instability of the stream channel caused by a 1984 <br />flood precluded [he installation of any type of monitoring station in the vicinity. <br />The bridge located immediately downstream of TR-a was replaced in [he fall of 2000 potentially altering [he current <br />stage rating curve. Therefore, the decision was made to update the stage/discharge curves for TR-a and TR-b. Over the 2001 <br />season, a total of nine cross-sections and associated velocities were measured at each cross section location. This data was <br />used to compute a stage rating curve ai each location <br />The stage rating curve for TR-a was developed from flows ranging from 1 I cfs [0 145 cfs. The curve equation and rZ <br />for the curve are as follows: y = 44.469x3~2N0~, where y =flow in cfs and x =depth of flow; r2 = 0.98. Flows for much of 2002 <br />were below [he 11 cfs used to develop the rating curve; therefore, the calculated flows may [o be low <br />The stage rating curve for TR-b was developed from flows ranging from 13 cfs to 144 cfs. The curve equation and rZ <br />for the curve are as follows: y = 65.049x2.431, where y =flow in cfs and x =depth of flow; rZ = 0.99. This appears to <br />indicate a good correlation between the upstream and downstream flows. <br />Additional measurements will be collected during the spring and early summer of 2002 to further refine the stage <br />rating curve for these locations. <br />2 <br />