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reach (Table 4), D50 ranged from 20 to 90 nun. Particle sizes were coarsest in the small . riffle located at the extreme downstream end of the reach, and were finest near the center of the reach (Fig. 15) Average boundary shear stress generated by the bankfull discharge of 105 m3/s (3700 fels) was sufficient to mobilize sediment similar to the sizes of particles found on 3 of the 6 representative pebble count locations in the study site when assuming t* 50 = 0.034 ('Fig. 16). The mobilized sites are located on the cobble bar that is in the riffle near cross-section 5 and 6, and had D50 values of 20, 24, and 32 nun. The location with the D50 of 32 nun was predicted to mobilize at discharges equal to bankfull, while the two sites with finer D50 would mobilize near 28 m3/s, which is 27% of bankfull. The other 3 sites, which have D50 values of 66, 81, and 90 nun, were not predicted to be mobilized at a discharge of 160 m3/s. When assuming t*50 = 0.060, only one gravel bar was predicted to move at bankfull discharge. At 160 m3/s (5700 fels) only 2 of the 6 bars were predicted to mobilize. Analysis of Sediment Records-Effective Discharge Sediment transport on the White River was measured between 1975 and 1990. The strong correlation (r = 0.77) of this relationship (Fig. 17) describes the increased ability of the river to transport sediment at increasingly higher discharges. We extrapolated this sediment transport rating relation to the entire available discharge record and found that the majority of sediment transported by the White River is carried by 2 different ranges of discharges; very low discharges of between 11 and 17 m3/s (400 and 600 rels), and moderate discharges around 60 m3/s (2100 fefs) (Fig. 18). Discharges 22