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(Wesche and Rechard 1980; Leathe and Nelson 1986) techniques were used to analyze the effect of flow regime modification on trout habitat. Each technique was employed at all sites except for FPR-BP, at which habitat time series analysis was not conducted since the channel type associated with FPR-BP was directly related to dam construction and strongly influenced by man-made features. Habitat time series analysis allows the direct comparison of multiple flow regimes on the trout habitat quality. Pre-dam and post-dam habitat was compared at FPR-HG and FPR- LG. The wetted perimeter technique evaluates the decline in wetted perimeter as a function of discharge. Based upon this relationship, an "inflection" point was determined for riffle transects. Because a riffle transect was not modeled at FPR-BP, an inflection point is reported for the run transect at FPR-BP. Below the inflection point threshold, wetted perimeter declines rapidly for relatively small reductions in discharge (Annear and Condor 1984). Macroinvertebrates Benthic macroinvertebrate sampling was conducted during spring (30 April) and fall (11 October) of 2001, and spring (1 May) 2002. Four sites were sampled in spring 2001 while five sites were sampled on later dates. Site locations in the Roaring Fork River are provided in Figure 2. Figures 3 and 4 provide site locations on the Fryingpan River. At each location, three samples were taken in riffle habitat using a Hess Sampler with 500 µm mesh in order to provide quantitative macroinvertebrate data. All samples were taken in areas of similar size substrate and similar depth to avoid bias that may be directly related to habitat. Depth at each sample location ranged between 24.4 cm and 33.5 cm. Substrate within the Hess Sampler was thoroughly disturbed and individual rocks were scrubbed by hand to dislodge all benthic organisms. Draft Final Report, Fryingpan and Roaring Fork Rivers February 12, 2003 Miller Ecological Consultants, Inc. Page 17