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collected at an ungaged site, Yampa River at Canyon Entrance, to check the accuracy of measurements made at the Deerlodge Park site. The channel at the Canyon Entrance site, which is confined by bedrock and talus, provides a good hydraulic control for water and sediment-discharge measurements. Suspended sediment was collected at station 09260050 Yampa River at Deerlodge Park at verticals spaced every 15 ft across the channel with a DH-48 or 0-74 depth-integrating sampler (Guy and Norman, 1970). Observed suspended-sediment concentrations varied from 137 mg/L to 5,600 mg/L. Bedload was collected at 15-ft intervals across the channel at the Deerlodge Park site using a Helley-Smith bedload sampler (Helley and Smith, 1971; Emmett, 1980). Bed-material samples were collected with a pipe dredge (6-in. diameter) at 50-ft intervals along the cross section. Concentrations and size distribu- tions of suspended sediment collected at station 09260050 Yampa River at Deerlodge Park are shown in table 8. Size distributions of bed material are shown in table 9 and size distributions of bedload are shown in table 10. Discharge, hydraulic-geometry and sediment.size data from station 09260000 Little Snake River near Lily are shown in table 11, and similar data from the ungaged site, Yampa River at Canyon Entrance, are shown in table 12. Tables 8-12 are presented in the Supplemental Data section at the end of the report. Sediment discharges in the Yampa River at Deerlodge Park were computed from 33 measurements made over a range of discharges. Suspended-sediment di scharge in the sampled zone was computed from the mean di sCharge-wei ghted sediment concentration, the measured water discharge, and a unit conversion constant (Porterfield, 1972). A correction factor to acco.unt for the percent- age of streamflow actually sampled with the depth-integrating sampler was applied to the computation of discharge of suspended particles that would also be collected near the bed in the Helley-Smith sampler (particle diameters larger than 0.25 mm), (Colby, and Hembree, 1955). Bedload discharge was computed by dividing the dried sample weight by the total sample time and by the width of the Helley-Smith sampler orifice (0.25 ft),' and multiplying by the channel width. Total.sediment discharge was determined as the sum of suspended-sediment di scharge and bedload di scharge. Size di stri buti ons of suspended sediment (table 8) and bedload (table 10) were combined with the appropriate suspended-sediment discharge and bedload discharge to compute sediment discharges by size range. Water discharge, total sediment discharge, suspended-sediment discharge, bedload discharge, and the total sediment discharge in several size categories are presented in table 13 in the Supple- mental Data section at the end of the report. The size distribution of material transported by the Yampa River at Deerlodge Park is summarized in table 2. Most of the riverbed consisted of sand-size material during all discharge measurements in 1982 and 1983. 80th the bed material of the channel and the bedload were predominantly medium-to- coarse sands. The average of median grain sizes (dso) for bed-material samples was 0.61 mm, and for bedload was 0.57 mm. Bed-material samples that included minor amoLlnts of gravel were highly skewed. Suspended sediment at the Deerlodge Park site varied considerably in size distribution. Silt- and clay-size material (sediment finer than 0.062 mm) comprised 10 to 92 percent of the total suspended-sediment discharge; the mean was 60 percent and the standard deviation was 23.7 percent. The remainder of suspended sediment was 13