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table 13 in the Supplemental Data section at the end of this report). The sum of the annual sand-gravel- and silt-clay-size loads, which should equal-the annual total sediment load, was 1.80 million tons--12 percent less than the computed annual total sediment load. This discrepancy probably exists because of the relatively poor definition of sand-gravel- and silt-clay-size material discharges by the linear regression equations in table 3. Sediment loads were not computed for any other particle-size categories presented in table 3 because of low R2 values and high standard errors of estimates associated with those transport equations. Table 5.--Annual sediment Loads, station 09260050 Yampa River at Deerlodge Park Type of sediment load Measured (tons per year) Estimated with Modified Einstein (tons per year) Total------------------------------ 2,040,000 2,420,000 5uspended-------------------------- 1,940,000 1,880,000 Bedload---------------------------- 100,000 --------- Sand and gravel-------------------- 790,000 1,040,000 Silt and clay---------------------- 1,010,000 1,050,000 Annual sediment loads for the Yampa River at Deerlodge Park a]so were computed with sediment transport equations derived from sediment discharges estimated by the Modified Einstein procedure (table 4). Annual sediment loads computed from estimated sediment discharge data were compared to annual sediment loads computed from measured sediment discharge data (table 5). Annual total sediment load computed with the sediment transport equation derived from estimated sediment discharges was 2.42 million ton/yr, a value 16 percent greater than that computed with the sediment transport equation derived from measured sediment discharges. The Modified Einstein procedure does not provide a bedload estimate; therefore, no annual bedload discharge was computed. Closer inspection of the annual sediment loads in table 5 reveals that the annual silt-clay size load computed with the sediment transport equation derived from estimated sediment discharges was only 4 percent greater than the annual silt-clay-size load computed with the equation based on measured sediment discharges. 8y contrast, the annual sand-gravel load computed with the equation based on estimated sediment discharges was 32 percent greater than the annual sand-gravel load computed with the equation based on measured sediment discharges. The discrepancy in computed sand-gravel loads is proba- bly due to undersampling of bedload by the Helley-Smith sampler, overestima- tion of sand and gravel discharges by the Modified Einstein procedure, or cumulative error that resulted from using sediment transport equations that 20