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3 Results and Discussion Final map plots and acreage tabulations were hand delivered to Mr. Bob Williams. GenerallYt the number and total acreage of backwaters are maxi- mized at lower flows (see Appendix A and B). Howevert because only three flows were studied, it is not certain what flow will produce the optimum number of backwaters. This number may occur at a higher or lower flow than the 1,889 ft3/s reported in this study. Additionally, the highest flow studied (4,359 ft3/s) maintained larger backwaters than the lowest (1,889 ft3/s) and middle (3,119 ft3/s) flows; therefore, it is possible that a different high flow scenario may maximize backwaters. More flows need to be studied to determine the optimum strategy. Furthermoret a greater number of study sites encompassing larger river reaches should be examined to reduce the variability in the data. The Ouray study site maintained the greatest number and acreages of back- waters at the highest flow. This may have occurred because the sandbars in this study s'ite are higher in elevation, steeper, and more permanent (vegetated) than the sandbars in the other areas. Thus, backwaters on higher sandbars only occur at higher flows. Comparing 1:4,000 and 1:2,000 scale photography indicates the former is adequate for mapping backwaters. Cost savings dictate the use of 1:4,000 scale photography. Color infrared photography appears superior to color photography since color infrared increases the contrast between water, sand, and sediment laden water. Moreover, backwater delineation is simpler and more accurate using color infrared photography. In our efforts to obtain a fourth set of photography, an interesting observation occurred. We requested flows of 1,500 ft3/s in order to help define the lower end of the graphs. More specifically we felt that with a 1500 cfs data set it would be possible to focus in on the range of flows needed to maximize backwater habitat. A fourth set of aerial photography was acquired on December 4, 1986, almost 3 months after the first low flow. The Jensen Gage reading was nearly identical to the September 12, 1,986, It889 ft3/s flow record. It was then determined that it would be unneccessary to interpret this data as results would probably be iden- tical to the September 12, 1986 data set. After a brief examination of the photographs, it was noted that sandbar configuration and backwaters were drastically changed. Moreover, there was an average of approximately 30 percent loss in the area of sandbars calculated at the same flows in the same study sitest 3 months apart. (see map plots and Appendix A for acreage tabulation and a visual account of cover type changes). On the Ouray site, an important backwater near mile 135.2 was reduced to a