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Another study site was added in 2000 and was named the Clifton Site. This station is just upstream with only a short section (about 300 m) between it and the Corn Lake site. The Clifton site is from RM 177.7 to 180.4 and has a total length of 4.1 km. In this section, the river has split flow in two large sections of the channel and there is an old diversion structure located at RM 179.7. This structure backs up water along the north shoreline and there is a large backwater at lower flows, but smaller backwaters are not common in this site (Figure A54). The peak flow for the Palisade gage in 1999 was 12,700 cfs on June 10. The peak flow in 2000 was 13,500 cfs on May 31 and in 2001 the peak flow was 8,410 cfs on May 21. The median peak flow for the II-year Palisade gage history is 13,500 cfs indicating that peaks for 1999 and 2000 were near normal. Typically, flows in March are near 2,000 cfs, but in some years flows can drop after April 1 due to diversions into the Government Highline and Grand Valley canals. In 1999, flows during the ascending limb (April and May) of the hydro graph flow dropped to 435 cfs on April 15, 1999 and was the minimum flow for the year. The minimum spring flow was 1,110 cfs on April 5th, 2000, and it was 500 cfs on April 17th, 2001. Summer flows were much less in 2000 and 2001 than in 1999 and as was the case for the Yampa River, this provided an opportunity to sample the fish population at reduced flows. Osmundson et al. (1995) made instream flow recommendations for the IS-Mile Reach based on a study of habitat availability for endangered fish. The recommendations from Osmundson et al (1995) were somewhat complex because he wanted to avoid using a single minimum flow. These in stream flow recommendations were given as mean monthly (not mean daily) minimums flows and varied by season and depending on wet, average, and dry flow-year categories determined from historic flow data. The lowest mean monthly flow recommendation is 810 cfs (Table 1), and it should only occur at the same frequency as dry years, which he defined as two in ten years. In half the years, the mean monthly minimum flow for August to September should have exceed 1,630 cfs (Table 1). 8 I I I I I I I I I I I I I I I I I I I