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<br />Alpha, the velocity head coefficient was computed from discharge <br /> <br />measurements and was found to range from 1.0 to 2.0 in these steep <br /> <br />channels. Alpha showed a sl ight tendency to increase with an increase <br /> <br />in Manning's roughness coefficient, but this was not always the case. <br /> <br />A relation between alpha and the other hydraul ic or bed material prop- <br />erties was not developed because of the complexity of the relation of <br /> <br />alpha to these variables. These alpha values were computed from veloc- <br /> <br />ity estimates based on the one- or two-point methods. Further studies <br />are needed to evaluate alpha using multiple-point velocities on steep- <br />gradient streams. <br /> <br />Vertical-velocity measurements were randomly taken for several <br /> <br />depths of flow at a few of the sites. These data indicate that the <br />'vertical-velocity profile does not fit the assumed logarithmic vertical- <br /> <br />velocity distribution. The mean veloCity in each subarea was under- <br /> <br />estimated when using the one-point or two-point method. The discrepancy <br /> <br />between the actual and measured vertical velocities becomes greater as <br /> <br /> <br />the depth of flow decreases. This is probably why the prediction equa- <br /> <br /> <br />tion underestimates Manning's n at low flows. Furthe( studies are <br /> <br /> <br />needed to evaluate the vertical-velocity distribution of steep-gradient <br /> <br /> <br />streams. <br /> <br />a <br />