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material at each side. Cross sections were spaced approximately one channel width apart, and were oriented perpendicular to the flow. Cross section endpoints were monumented with either rebar or fence posts pounded to depths such that about 10-cm were exposed above ground surface. Transects were measured by attaching a length-calibrated Kevlar (Tradename) tag-line to the endpoints. A geodetic total station was used to measure ground-surface elevations under the tag line as well as to measure water-surface elevation and elevations of geomorphic surfaces near the channel. Elevation of cross section endpoints were all surveyed to a common reference datum. Elevation of the bed was measured either using the total station and a stadia rod placed on the bed at fixed intervals under the tagline, or was measured from a cataraft equipped with a paper-trace echo sounder and outboard motor. When measuring the bed from a raft, the boat operator maintained the boat carefully under the tag-line while slowly crossing the river. A second individual in the raft recorded depth using an echo sounder and position at marked locations along the tag- line. Measurements made from the raft were replicated at least four times. Where wading was feasible, bathymetric measurements made from the raft were also surveyed with the total station to verify the accuracy of the echo-sounder. Echo-sounder measurements concurred with total station measurements and rarely deviated more than a few centimeters. Coordinate data from the total station was reduced to distance and elevations relative to endpoints for purposes of plotting. Bathymetric traces of the bed were analyzed in the lab. Average depths below the water surface from the fourrepeated bathymetric surveys were converted to bed elevations by subtracting the depth of water from the surveyed elevation of the water surface. Transects were resurveyed in April 12