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<br />,
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<br />
<br />(cfs). Bank-backwater numbers were maximized at 1101 cfs,
<br />channel-backwater numbers were maximized at 1687 cfs and total backwater
<br />numbers were maximized at 1687 cfs. Figure 7 (Appendix A) presents
<br />backwater size distribution versus flow (cfs). The <20m2 size class was
<br />maximized at 1687 cfs, the >20m2<200m2 size class was maximized at 1687
<br />cfs, the >200m2<5002 size class was maximized at 1101 cfs, the
<br />>500m2<1000m2 was maximized at 1101 cfs, and the >1000m2 class was
<br />maximized at 1381 cfs.
<br />
<br />Ouray
<br />
<br />Table 5 (Appendix A) presents the area of each class for each flow at
<br />the Ouray site. The relationship between flow and backwater area is not
<br />as well defined at the Ouray site as it is at the Island Park and Jensen
<br />sites. There is a significant increase (122%) in backwater area from
<br />5,260 cfs [18,789 m2 (4.6 ad] to 2,423 cfs [41,722 m2 (10.3 ac)].
<br />Backwater area increased somewhat at 1,773 cfs and again at 1,667 cfs
<br />where backwater area was maximized at 52,057 m2 (12.9 ac). Large
<br />decreases occurred between 1,687 cfs and 1,430 cfs (23%) and between
<br />1,430 cfs and 1,381 cfs (23%). Finally, backwater area increased from
<br />30,835m2 (7.6 ac) at 1,381 cfs to 41,177 m2 (10.2 ac) at 1,101 cfs.
<br />Isolated pool area increased significantly at the lower flows and was
<br />maximized at 1,381 cfs with 31,182 m2 (7.7 ac).
<br />
<br />Table 6 (Appendix A) presents backwater number, size distribution, area,
<br />and average backwater size for each flow at the Ouray site. Total
<br />backwaters were maximized at 1,381 cfs (73) and were also high at 1,687
<br />cfs and 1,430 cfs with 70 and 66 backwaters, respectively. The lowest
<br />numbers of backwaters occurred at 5,260 cfs (44), 1,101 cfs (57), and
<br />2,423 cfs (58). With the exception of 5,260 cfs, there were more
<br />bank-backwaters than channel-backwaters at each flow. As occurred at
<br />the Island Park and Jensen sites, the >20m2<200m2 size class contained
<br />the most backwaters, both bank and channel. However, the Ouray site had
<br />a disproportionately higher number of very large backwaters (>1,000 m2),
<br />at all flows except 5,260 cfs. The large nature of backwaters at the
<br />Ouray site may account for the different relationship between flow and
<br />backwater area than at Island Park and Jensen.
<br />
<br />Closer analysis of individual backwaters indicates that a few extremely
<br />large backwaters (5,000 - 10,000 m2) which occurred at 1,687 cfs did not
<br />occur at lower flows, therefore, backwater area was much lower at these
<br />flows. The average size of all backwaters at the Ouray site was much
<br />larger than at Island Park and Jensen, ranging from 422 m2 at 1,381 cfs
<br />to 831 m2 at 1,773 cfs.
<br />
<br />Figure 8 (Appendix A) presents backwater area (m2) versus flow (cfs).
<br />Bank-backwater size was maximized at 1687 cfs, channel-backwater size
<br />was maximized at 2423 cfs and total backwater size was maximized at 1687
<br />cfs. Figure 9 (Appendix A) presents numbers of backwaters versus flow
<br />(cfs). Bank-backwater numbers were maximized at 1430 cfs,
<br />channel-backwater numbers were maximized at 1687 cfs and 1381 cfs, and
<br />total backwater numbers were maximized at 1381 cfs. Figure 10 (Appendix
<br />A) presents backwater size distribution versus flow (cfs). The <20m2
<br />size class was maximized at 1381 cfs, the >20m2<200m2 size class was
<br />maximized at 2423 cfs and 1381 cfs, the >200m2<5002 size class was
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