Streamflows and channels of the Green River basin, Wyoming

Width, depth, cross-sectional area, and velocity of streamflow were depicted for 51 gaged sites in or near the Green River basin of Wyoming by summarizing data obtained from current-meter discharge measurements. Using these at-a-station relations as a base, regional relations were then developed that characterize hydraulic features of streams throughout the study area. Channel size is an indication of flow magnitude. High flows affect channel formation, and the annual peak-flow array is a representation of these flows. The geometric mean of this array is a viable statistical index of channel-forming flows because it represents the relative magnitude of high flows at a site. Bankfull discharge is a physical index of flows dominating channel formation. The magnitude of the geometric mean approximately equates to bankfull discharge, on the average. Relations depicting hydraulic characteristics of a discharge equal to the geometric mean of annual peak flows may, therefore, be considered to be generally representative of channel conditions existing during bankfull discharge. The relations have application for predicting channel response to developments that would alter streamflow. (USGS)