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independent laboratory. Surface water data are contained in Appendix A and ground water data are contained in Appendix B. III. SURFACE WATER GAUGING STATIONS Figure 1 shows the continuous streamflow records for Trout Creek at TR-a and TR-b. The graphs showing the results of the gauging stations along Trout Creek indicate that the monitoring program is being placed on-line early enough in the year to record flow prior to the peak runoff period for each year. The graphs show the monthly average flows and give some indication of the variability between mild winters (winters of less snow accumulation) and harsh winters. The graph showing 1994-1996 data indicates a wide variation in the streamflow between 1999, 1995 and 1996. The 1987-1996 graph suggests that 1999 was the driest winter over the past decade and 1993 was the wettest. The flow record for 1996 shows the peak flow to have occurred in May as it did during 1987, 1992 and 1999. The early peak flows for these years was probably due to milder winters or the on-set of warmer temperatures occurring earlier in the spring. • The stage/flow rating curve for TR-a was reviewed in June of 1999 to ensure its continued accuracy. Sufficient differences in the channel cross-section at TR-a were noted during the review to warrant development of a new stage/flow rating curve. However, since the high flow period occurred in late May of 1999, data points representing the high flow period during 1994 were not obtained. Therefore, additional calibration flow and channel cross-section measurements were made during 1995 to cover the full range of stage/flow observations needed for the stage/flow curve to represent all stages of flow Over the 1999-1995 seasons, a total of five cross-sections (two in 1999 and three in 1995) were developed and compared to ensure channel stability. All of the cross-sections varied no more than three-tenths of a foot at each measurement point along the section. The variation among the cross- sections was primarily due to the specific placement of the survey rod on the creek's cobble lined bottom. An averaged cross-section was then developed for use with 13 sets of velocity data to compute a stage/rating cuzve. The stage rating curve data covered flows ranging from approximately two cfs to 85 cfs. The equation and r~ for the curve are as follows: y = 13.817x~'le3c where y = flow in cfs and x = depth of flow; rZ = 0.98. During 1996, cross-section measurements were taken periodically through-out the year which confirmed that the channel configuration had remained stable during the past annual monitoring period. • Instantaneous flow and continuous flow records are provided for TR-b. 2