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difference was between habitat types: depth-to-embeddedness was somewhat greater in riffles than in runs. Embeddedness in relation to flows During runoff in 1996, depth-to-embeddedness in select riffles and runs of strata 9 and 8 increased between the first and second sampling dates. This may have been because there was a second peak in flow between the two dates (See Fig. 7) which may have provided additional flushing of fines from the bed. Increases in DTE also occurred at select sites between the first and second sampling dates in 1997, though changes were generally not as pronounced as in 1996. The difference in years may be due to the absence of a flow spike between the two sampling dates in 1997. Discharge on the first sampling date in 1997 was higher than on the first date in 1996: 507 cros (17,900 cfs) versus 348 cros (12,300 cfs). In 1997, even though flows were declining, winnowing of fines may have continued to occur at certain sites after the first date if flows remained sufficient to move coarse bed materials. Alternatively, DTE may have not actually increased with declining flows at these sites as our results suggest; instead, they may reflect increases in DTE at different bank positions. Because we were moving down the bank on each runoff sampling date as the flows declined, DTE may have become higher simply because we were sampling in areas that had been under deeper water during peak flow: shear stress would have been higher under deeper water and more movement and cleaning of the bed may have occurred deeper in the channel than on the channel margins (John Pitlick, personal communication). According to Harvey et al. (1993), the conditions required to move bed materials in some riffles change as discharge declines because velocity through the riffle increases as the slope over the riffle increases. This was very likely the process that occurred within the small, steep chutes that laterally dissected the bar in reach 9-B during 1997. At this site, tertiary bars formed at the base of the chutes in much the same manner as at the Colorado squawfish spawning site in the Yampa River as described by Harvey et al. (1993), though here, the small tertiary bars were high and dry by the time of the estimated (temperatures > 20 C) spawning season (113 cros [4,000 cfs] on July 17). Depth-to-embeddedness remained relatively stable during base-flow periods of both years. Thus, the rate of re-sedimentation is not rapid following a flushing event, at least not during the subsequent summer and fall periods. Even after a rainstorm-induced flow spike in the 18- mile reach in September 1997, when turbidity conditions were observed to dramatically increase, depth-to-embeddedness did not decrease in any significant or consistent way. What occurs over winter and before the next spring runoff event is as yet unknown. To shed light on this question, future monitoring efforts should include a March sampling date. 25