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Peak flows recorded at the Maybell gage were fairly similar for the years 1998, 1999 and 2000, at 10,040 cfs, 9,980 cfs and 9,830 cfs respectively. Peak flows in these three years are near the magnitude of the median peak flow of 9,980 cfs for the 86 year period of record (Figure 2). Peak flow in 2001 was 7,650 cfs, which has been exceeded in 77% of the years during the period of record. The peak flow in 1997 was 16,400, and has been exceeded in only 5% of the period of record (Figure 2). Andrews (1982) calculated bankfull flow for the Yampa from the Maybell gage to be 9,.000 cfs. Determining impacts of low flows are one of the primary objectives of this study. Modde et al. (1999) used a cross section methodology (modified R2Cross) to identify habitat availability at low flows for endangered fish on the Yampa River. The result was a recommendation that 93 cfs be used as a reference flow that signals the beginning of severely degraded conditions. The 93-cfs reference flow was specifically not meant to be an instream flow recommendation since it was believed the endangered pikeminnow could likely survive severely degraded conditions for a short term. Annual minimum flows recorded at the Maybell gage for 1997, 1998, 1999, 2000 and 2001 were 320 cfs, 115 cfs, 166 cfs, 30 cfs and 50 cfs respectively. The 86-year median minimum flow is 126 cfs (Figure 3). The 2000 minimum flow of 30 cfs was exceeded in 93% of the years, and the 2001 minimum flow of 50 cfs was exceeded in 83% of the years for the period of record (Figure 3). Flow did not drop below the 93-cfs reference flow in 1998 and 1999, but flow was less than 93 cfs for 34 days in 2000 and 17 days in 2001. Two consecutive years of low flow may have more significant and lasting impacts on the aquatic community (carrying capacity) than a single low flow year. Stream flow was less than the 93-cfs reference flow for 0 days in 1997, 2 days in 1996, 0 days in 1995. In 1994, the minimum flow was 8 cfs and flow was less than 93-cfs for 73 days that year. Presumably habitat was severely restricted in 1994 and there were impacts to the fish community. The four-year interval between 1994 and the start of sampling in 1998 may have been enough time to allow the fish community to adjust back to normal flows. There were two days of flow below the 93 cfs in 1996. As of 2000, flow had not been below the 93 cfs for the previous three years. However, 2001 was a second consecutive low-flow year (Figure 3). 17