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where: W = flow width of stream, in feet; D = mean flow depth of stream, in feet; V = mean flow velocity of stream, in feet per second; and Q = water discharge, in cubic feet per second; using the symbols introduced by Leopold and Maddock (1953), in which a, c, and k are coefficients and b, f, and m are the exponents. The coeffi- cients represent the theoretical values of width, depth, and velocity when the discharge is unity (1.0), but on many rivers the discharge is never actually 1 ft3/s and so the coefficients have no physical meaning. The values of b, f, and m are the slopes of the respective lines. Variations in the values of b, f, and m among stations can be ex- plained by the general station locations. The station Big Sandy River at Leckie Ranch, near Big Sandy is located near the headwaters of the river; therefore, smaller values for b and f and a larger value for m are ob- tained. This is due to the bedrock control of the width and depth caus- ing a greater increase in velocity with increasing discharge. Pacific Greek is located in the plains where the erodible channel allows a change in depth and width with increasing discharge; therefore, a smaller in- crease in velocity occurs with increasing discharge than at the station on the Big Sandy River at Leckie Ranch. Some errors in the values of b, f, and m in table 5 are present due to the techniques of data collection. Data collection during the high flows on the Big Sandy River at Gasson Bridge near Eden were made from a bridge, while at low flows other cross sections were used. The bridge measurements yielded a smaller than average value for b and a larger than average value for f because the bridge revetments confine the width of flow, causing the depth to increase more rapidly. At other locations where wading measurements were made, for example the Big Sandy River near Farson, the original cross section was not always used during subsequent measurements. Wider than average sections were used at high discharges to obtain depths shallow enough for wading. Bankfull values of discharge and the bankfull width--depth ratio (H. W. Lowham, U.S. Geological Survey, written commun., 1978), also are presented in table 5. The bankfull discharge is commonly considered the most important factor in forming the channel. The width-depth ratio is an indicator of the main type of sediment load carried by a stream. A large width-depth ratio generally indicates a bedload stream while a small ratio generally indicates a suspended-load stream. The nature of these types of loads is explained more fully in later sections of the report. 21