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<br />This decrease in isolated pools, as well the large increase in
<br />backwater area from 1,430 cfs to 1,381 cfs, may be attributed to
<br />the chronological order of these flows. Backwaters at 1,381 cfs
<br />and 1,101 cfs were allowed to form during a gradually descending
<br />hydrograph. The 1,430 flow was obtained immediately after the
<br />lowest flow of the season (approximately 1,000cfs - see Appendix
<br />B). Furthermore, this flow was not allowed to stabilize and only
<br />occurred for one day, which very likely affected backwater and
<br />isolated pool formation.
<br />
<br />Table 2 (Appendix A) presents backwater number, size distribution,
<br />area, backwater area and number per mile, and average backwater
<br />size for each flow at Island Park. The relationship between flow
<br />and backwater number was not as clear as the flow\area
<br />relationship; however, backwater numbers were maximized at 1,381
<br />cfs and 1,101 cfs, with 56 and 52 backwaters, respectively. The
<br />1,773 flow produced 45 backwaters, while the 210west number of
<br />backwaters occurred at 2,423 cfs (32). The >20m <200m size class
<br />consistently represented the highest number of bOth bank- and
<br />Channel-backwaters. Very large backwaters (>1,000 m) were more
<br />abundant at the lower flows. Channel-backwaters were slightly more
<br />abundant than bank-backwaters which was expected because of the
<br />braided nature of the Island Park site; however, the average
<br />bank-backwater was substantially larger than the average
<br />Channel-backwater. Backwater number per mile ranged from 5.6 at
<br />2,423 cfs to 9.8 at 1,381 cfs, which was the most for any site.
<br />Figure 2 (Appendix A) graphs backwater nUmber\mile for ea2h flow at
<br />each site. Bac~ater area per mile ranged from 1,379 m at 5,260
<br />cfs to 3,886 m at 1,101 cfs, which was second only to the Ouray
<br />site. Figure 3 (Appendix A) graphs backwater area\mile for each
<br />flow at each site. The average size of all backwaters uSU2lly
<br />increased at lower flows, and was maximized at 1,101 cfs (426 m ).
<br />
<br />Jensen
<br />
<br />Table 3 presents the area (m2) of each class for each flow at the
<br />Jensen site. Generally, an inverse relationship between flow and
<br />backwater area occurred similar to that at the Island Park site.
<br />Again, the largest increases in backwater area occurred bitween
<br />2,423 cfs and 1~773 cfs where area increased 49% from 7,328 m (1.8
<br />ac) t~ 10,944 m (2.7 ac) and bet~een 1,430 cfs and 1,382 cfs where
<br />area lncreased 37% from 15,014 m (3.7 ac) to 20,569 H (5.1 a2)'
<br />Total backwater area was maximized at 1,381 cfs (20,569 m).
<br />Isolated pool area increased at the lower flows, again with the
<br />exception of the 2,430 flow. Isolated pool area was ~aximized at
<br />1,101 cfs (9,007 m ) and was lowest at 5,260 cfs (372 m ).
<br />
<br />Table 4 (Appendix A) presents backwater number, size distribution,
<br />area, and average size for each flow at the Jensen site. Total
<br />
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