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<br />~ <br /> <br />c' <br /> <br />When streamflow was 10~I, a transit-stadia survey was made of each <br /> <br />reach. The information obtained from these surveys was used to con- <br /> <br />struct cross sections at a common datum. Photographs were also taken of <br /> <br />each reach. <br /> <br />The size distribution of the bed materials was determined by meas- <br /> <br />uring the intermediate diameters of sampled particles (Wolman, 1954). <br /> <br />Measuring particle sizes on streams with deep, fast-flowing water and <br /> <br />large boulders presented several problems. Fortunately, the particle- <br /> <br />size measurements could be made during the low-fl-ow season when depth <br /> <br />and velocity were at a minimum. However, many of the boulders were too <br /> <br />large to pick up and measure. Bed material was packed tightly together <br /> <br />at most sites, making removal and measurement of the particles difficult. <br /> <br />In these cases, the intermediate particle axis had to be measured in <br /> <br />place. <br /> <br />/g <br /> <br /> <br />Because of these limitations, an alternative method of measuring <br /> <br />particle size was concurrently made on the same bed material. A grid <br /> <br />system was laid out at each site and 50-100 samples of bed material were <br /> <br />measured at a specific spacing. Prior to picking up the particle, its <br /> <br />height above the average streambed just upstream from the particle was <br />/ <br />measured using a wading rod marked in tenths of a foot. Similarly, the <br /> <br />width of the rock normal to the flow was also measured. This method was <br /> <br />much easier to use than the Wolman (1954) method. <br />