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transported in the White River was moved as a pulse of mobilized bedload material. Whereas the bed scoured at higher discharges in most of the measured cross sections, aggradation occurred near the coarsest cobble bars. Aggradation ofthe bed in these regions could be due to finer material moving over the more stable coarse material, which suggested the occurrence of selective transport. Other studies found that transport of finer bed material occurred at discharges below bankfull stage in several coarse-bedded rivers. The channel of the White River within the study reach was made of both fine-grained and gravel deposits. While some of our evidence suggested that a threshold of equal mobility was reached near 41 m3/s (1,450 fe/s), it was more likely that selective transport ofthe finer deposits occurred at this discharge. Both the aggradation of the bed at higher discharges in very coarse bedded areas of the stream, and a peak in the sediment transport curve at 14 m3/s (500 fe/s), suggested that finer sediments were transported selectively at low discharges. Base flow/low flow recommendation: The purpose of this study was to identify the base flow needs of endangered fish, i.e., adult Colorado pikeminnow, in the White River. Two approaches were used: 1) protection of Colorado pikeminnow habitat and 2) protection of riffle habitat to maintain biological productivity. Both methods used physical habitat simulations to estimate changes in macrohabitat (pool, run, eddy, and riffles) and microhabitat (depth, velocity, substrate, and cover) changes that resulted from changing flows. Curve break analysis was used to identify the flow below which the greatest rate of habitat change occurred. Study results showed that most of the habitats in the White River consisted of riffles and runs, and pools and eddies were secondary components. Habitat proportions remained constant as discharge ranged from 4.2 to 17.0 m3/s (150 - 600 fe/s) ; below 4.2 m3/s (150 fe/s), riffles 6