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" . v"~.' -, ~ , f.~ ot;-ers, 13(5). Other sLispended-sedi;ent :-:'e2s:..:re:erts '..:ere made perrodi:al1y fc- t~~ Ya:pa River near May~el I and Little Sna<e River near Lily as Dart o~ the Nar: :onal 5tream Qual it)' Assessment Neti..:Jrk (';ASQ!-.tl) program (Fic;"e ane Ha".~ins:Jn, 1975). +-he frequency of data collection at these stations has change~ during the 1976 water year to a dally frequel1cy for the Yampa ~iver near ~ay:el I and to a weekly frequency for the Little Snake River near Lily. Also, ~aily or monthly sedlment measurerents are nade at several gaging statlors in the Yampa River subbasin as part of ongoing cooperative prcgra~s (" S ,,1 . I S 1076' li. . -.:2010glca urvey, j J. I I~ethod of Corputar:ien -.,,,,,", - Estimates of me.on-annual sediment 10&ds for the 17 selected gaging statior.s in theYamp.a River basin (flg.1),':ere computed using the.-rIO\,,- duration, sediment'::transport::curve method cesccibed .by Mi 11er" (1951). This method is useful when the 929)ng-stafiori""recol-d of streamflows is sufficient to def i ne the...L.r.e'ftrency of occurrence of var i ous discharges, and vihen sedi;;)er,t data, are 1 imited. A sediment-transport curve relating the dai ly suspen~ed-sediment load and dai 1y water discharge was developed for each of the 17 statio~s based upon the available measurements. Similarly, a relatio~ between the computed bedload-transport rates and discharges was developed as described subsequently. A total-'sediment-tra::sport curve was determined by su~ming the suspended-load and ~edload relations. Then, the total-sediment- load relation was combined with the average-annual frequency of occurrence of various discharges recorded at each gaging station to obtain the mean-annual total-sediment load at that location. Total-Sediment-Load versus Discharge Relations An example of how the total-sediment-discharge versus water-discharge relations were constructed for each of the gaging stations is illustrated in figure 2. As noted previously, the total-sediment discharge was composed or two pa~ts, the suspended load which waS measured and the bedload which was computed. Initially, sediment-transport curves relating the measured suspenjed load and the computed bedload to the water discharge were dev~lcped separately. The suspended-sediment-discharge versus water-discharge relation was determined by plotting daily mean suspended loads against the daily mean discharges. A mean relation, shown by a dashed I ine in figure 2, was calcu- lated by a least-squares linear-regression f~nction of the log-transformed da ta. lne bedload-transport-rate p~ted by the Meyer-Peter and bedload-transport rate (I,), is versus '.'Iater-discharge relations \,:ere co/- Mueller (1948) equation. The total channel given by: .ib ( 1 ~ = 2. 52D%O v.."':: 5'~ , .., O.86DJ!i[.7 r;!. " 7