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2000 1800 1600 " I I I 1400 _ I I I 1200 II I II I I I I Mean daiily cfs I.' peaked on 9/21/97 II al 6770 cfs I \ , ,-. I' ", II i ~\" ~r' . " ~ .... _1996 _ .1997 _50% ~80% - .:l \J '-' ~- blI loc = -= \J ~ S .. . /" I I I 1000 - ~ ._tj \ ; ~: 800 I . , " 600 '-"'" , 400 200 o l-Aug ll-Aug 21-Aug 31-Aug 10-Sep 20-Sep 30-Sep la-Oct 20-0ct 30-0ct Figure 3.1. Fall flows for 1996 and 1997 with reference flows for 50% and 80% daily exceedance. Over 500 habitat clusters were delineated on the Yampa River between Echo Park and Craig, Colorado. Cross section data were collected from 43 randomly selected habitat clusters (8.6% of the study reach). Habitat sequences were surveyed in 17 habitat clusters in the lower river reach (5 in Stratum 1, 8 in Stratum.2, and 2 each in Strata 3 and 4) and 26 clusters in the upper river reach (9 in Stratum 6 and 17 in Stratum 8). Within the 43 habitat clusters, 220 cross section profiles were measured in the Yampa River study area. At each cross section, a measuring tape was stretched between head pins set at or above the grassline on both sides of the river channel. The channel slope and water surface elevation were determined using a stadia rod and standard surveying level. Distance between cross sections and differences in water surface elevations were used to determine the slope of the channel (Bovee and Milhous 1978). The first cross section was placed at the most suitable hydraulic control in the cluster, just above a riffle at the downstream terminus of each cluster. The next cross section was placed upstream of the control, across the lower end ofthe adjoining mesohabitat. Cross sections through the middle and upper run, and 41