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I I I I I I , I I I I I I I I I I I I 25000 20000 1997 - 16,400 ets iii' ~ 15000 ~ o ;;: '" :: 10000 Q. 2001 - 7,650 ets 1998 - 10,400 cis 2000- 9,83Octs ~ 5000 1999 - 9,980 cis & Median o o 0.7 0.9 1 0.8 0.2 0.3 0.4 0.5 0.6 0.1 Exceedence Frequency Figure 2. Peak flow during the study period at the Maybell gage with exceedence frequency for the period of record. Minimum flows recorded at the Maybell gage for 1997, 1998, 1999, 2000 and 200 I were 320 cfs, 115 cfs, 166 cfs, 30 cfs and 50 cfs, respectively. The 86 year median (50% exceedence flow) minimum flow is 126 cfs (Figure 3). The 2000 minimum flow 000 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 93 cfs in 1998 and 1999, but flow was less than 93 cfs in 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. Again, using the 93-cfs reference flow (Modde et alI998), flow was less than 93 cfs for 0 days in 1997,2 days in 1996, o 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 a carrying capacity based on physical habitat availability provided by nonnal base flows. There were two days offlow below 93 cfs in 1996 and these were 79 and 88 cfs. In 2000 flow had not been below 93 cfs for the previous three years. However, 2001 was a low flow year that immediately followed a low flow year (Figure 3). 5