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<br />Strata 6 <br /> <br />Clusters 2 (rm 62,8) and 3 (rm 63.5) <br /> <br />Nine cross sections were surveyed in these two clusters along with depth profiles across two <br />shallow riffles. The length of the reach was 2, 646 feet. At 132.2 cfs, the mean flow measured in <br />the field (Table 2), shallow runs were 45%, shallow pools were 38%, and deep runs were 14% of <br />the total surface area of the reach (Appendix 2, Table 6). No Class I pool habitat was found at any <br />flow. Shallow habitats dominate this reach at flows below 400 cfs. The primary habitat available <br />for adult CS in this half mile of river is the deep run. <br /> <br />Cluster 7 (rm 73.3) <br /> <br />Five cross sections were done in this cluster. The sequence was 1,205 feet in length. Discharge <br />determined by field measurements was 287 cfs (Appendix 2, Table 7), The downstream control <br />cross section had to be located in a spilt channel, with 267 cfs in the main channel or right bank <br />(looking upstream) and 20 cfs flowing in the smaller channel around a small island. Flow was in a <br />single channel for all other cross sections in this sequence. <br /> <br />The run in this sequence was slow, deep and had a maximum depth of 7.3 feet (cross section 3) <br />at the field measured flow (288 cfs). This deep run was at the base ofa cliff just downstream ofa <br />bend in the river. The slope of this run was flat and the width/depth ratio was low. A drop in flow <br />from 288 cfs to one cfs lowers WSL by 2.5 feet at cross section 3. At one cfs, much of this run <br />modeled to be a Class II pool because depths were still up to 4 feet. The Class II pool is the <br />dominant habitat type of this sequence at flows between one and 40 cfs (Appendix 2, Table 2). <br />Percentage of usable habitat increased as l10w drop below 60 to one cfs, due to expanded influence <br />of the Class II pool. At l10ws over 60 cfs, shallow runs are the most common habitat type. <br /> <br />Cluster 11 (rm 78.8) <br /> <br />There were six cross sections surveyed at this sequence. The reach length was 1,772 ft, and <br />now measured in the field was 134.9 cfs (Appendix 2, Table 8). The control cross section was <br />located upstream of a steep shallow rift1e and upstream an exposed bar that split flow into two <br />channels. Flow in the channel left of the bar was 78 cis (63%) and was 46 cfs (37%) on the right <br />(looking upstream). Cross section 2 was located 380 ft above the control and just upstream of a <br />small flowing side channel (13.5 cfs). The flow of this side channel rejoined the main channel at <br />the base of the riffle below the control. This was the only option for a control site in this cluster and <br />in spite ofthe complex channel morphology, the control cross-section modeled without problems. <br />Flow was confined within a single channel in all other cross sections in this sequence. <br /> <br />Cross sections 2 and 3 described the lower and the middle of the run, respectively. The distance <br />between eross sections 2 and 3 is 850 feet and the increase in water surfaee elevation was 0.03 feet. <br />This run maintained width and depth at decreased flows and at one cfs, 42% of the sequence was <br /> <br />32 <br />