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RESULTS Island Park No significant regressions occurred at any site when the 142 m3/s flow was included in the analysis. However, when this flow was deleted from the analysis, a significant (P ~ 0.10), negative regression occurred at Island Park (r = -0.76). Backwater area generally increased as flow was decreased from 142 to 37 m3/s (table 1). Two substantial increases occurred: while flows dropped from 71 to 55 m3/s (30-percent increase) and from 46 to 45 m3/s (50-percent increase). Backwater area was maximized at 37 m3/s. The relationship between riverflow and backwater number was not as clear as the flow I area relationship, and there was no significant regression for flow versus number of backwaters at any site. However, backwater number was maximized at 45 and 37 m3 Is, and the lowest number of backwaters occurred at 71 m3 Is. The > 20m2 <200m2 size class consistently represented the highest number of backwaters. Very large backwaters (> 1,000 m2) were more abundant at lower flows. Backwater number per km was the greatest of any site. Backwater area per kilometer at Island Park was second to the Ouray site. The average size of all backwaters usually increased at lower flows, and was maximized at 37 m3 Is. Jensen A significant negative regression (P ~ .05) also occurred at Jensen (r = -0.82) when 142 m3/s was deleted from the analysis. The largest increases in backwater area occurred between 71 and 55 m3 Is when backwater area increased 49 percent and between 46 and 45 m3/s when area increased 37 percent (table 2). The backwater area was maximized at 45 m3/s. Total number of backwaters was greatest at 53 m3/s (table 2). Backwaters were generally more prevalent at the lower flows and were least abundant at 142 and 71 m3/s. The >20~200m2 size class contained the most backwaters. The largest backwaters (> 1,000 m2) generally increased in number at lower flows. Total backwaters per km were slightly less than at Island Park (table 2). Ouray The relationship between flow and backwater area at Ouray was not consistent and the linear regression was not significant (r = +0.09). There was a large, steady increase in backwater area from 142 m3/s to 53 m3/s; however, decreases in area occurred between 53 m3js and 46 m3js, and between 46 and 45 m3/s (table 3). Total backwaters were maximized at 45 m3 Is and were also high at 53 and 46 m3 Is (table 3). Again the >20~200m2 size class contained the most backwaters. However, Ouray had a disproportionately high number of large backwaters (> 1,000 m2) at all flows except 142 m3/s. The average size of all backwaters at Ouray was much larger than at Island Park and Jensen. Backwater area per kilometer was also larger at Ouray than at Island Park and Jensen. 3