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Figure 2. Badger Creek Rapid (mile 8.0)(continued). C. September 5, 1994. A debris flow from Jackass Creek (mile 7.9-L) on August 19, 1994, constricted Badger Creek Rapid. Most of this constriction was removed by the 1996 controlled flood release from Glen Canyon Dam. The sand bar on river right is depleted, probably as a combined result of the high-water years of 1983- 1986 and wind deflation. Other changes include the increase in tamarisk (Robert H. Webb, Stake 2862). ~ 1954-1955, a flood removed large redbud trees from the mouth of an unnamed canyon at mile 38.7-R, and a "heavy flood" down Red Canyon (mile 76.7-L) cut a channel5-feet deep and 40-feet wide. Also in 1955, a flood cut a large swath through a sand bar at Spring Canyon (mile 204.3-R). A flood in Deer Creek (mile 136.2-R) in 1956 filled the pool with sediment and rearranged boulders in the mouth, and a Diamond Creek (mile 225.8-L) flood changed the channel at its mouth. Reilly was particularly impressed with the effects of tributary flooding in 1961; a new deposit filled much of the pool beneath Deer Creek Falls and the mouth of Tapeats Creek (mile 133.8-R) shifted downstream. Although he accurately described changes he saw in the 1950s, he made additional observations on dam-related and other changes during trips in 1982 and 1984. A few of the later observations were inaccurate; for example, Reilly erroneously ~ thought that the Quigley grave at President Harding Rapid (mile 43.2) was removed by a flood between 1964 and 1982, but the grave is still present. The relatively few observations of debris-flow deposits before Glen Canyon Dam is significant. Before the Old Timer's Trip, we already knew from repeat photography and historical records that many debris flows had occurred in the last 15 years and that few could be identified from the pre-dam era. It is unlikely that Colorado River floods completely removed the evidence before the Old Timers could see the changes. Most pre-dam river trips occurred in the summer months, when debris flows are most likely to occur, or in the fall, before the spring floods could rework the deposits. In fact, Reilly and Nevills each saw evidence of streamflow floods, not debris flows. Both Litton and Cross II commented on the extensive channel changes associated with the December 1966 flood in Bright Angel Creek (mile 87.8-R). Historical photographs, notably those by SPECIFIC CHANGES OBSERVED IN GRAND CANYON 11