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Several cross sections were monitored with a sonar depth chart recorder. These cross <br />sections were surveyed to an appropriate station in the river where the transducer height was <br />calibrated. A depth chart recording of the bottom was then printed as the boat was pulled <br />along the tagline. A strip mark was recorded on the chart each time the transducer passed over <br />a 10 foot tagline station. The depth chart data was reduced in the office and transcribed to file <br />with the remainder of the surveyed data. <br />B. Discharge. Standard USGS stream discharge measurement techniques and <br />equipment were applied in collecting the river discharge measurements. This included a Price <br />AA current meter and digital readout meter manufactured by Teledyne Gurly. Velocities were <br />measured using the 0.2-0.8 depth methods if the depth was greater than 2.5 ft and 0.6 depth <br />method for depths less than 2.5 ft. Velocity measurements were taken for at least 20 intervals <br />per cross section. <br />Discharge measurement was not a focus of the study. Reliable river discharge data was <br />available from the USGS. Jensen gage 3.5 miles upstream, so only a few discharge <br />measurements were made to determine the split flow around the spawning bar island. The <br />USGS gaging station discharges were used for all subsequent analysis and there appeared to <br />be no significant gains or losses through the seven mile study reach. <br />C. Bed Material Samples. Some bulk bed material samples were collected at various <br />stations at cross sections E-4 and E-5 during each of the three field trips to determine any <br />variation of the bed material size during the flow season. These samples were collected by <br />shovel or by hand at low flows or by sampler from the boat at high flows. Cobble and gravel <br />samples generally averaged 30 to 50 lbs and were collected in large, heavy-duty plastic bags. <br />Sand samples were delivered to the laboratory in cups. The samples were analyzed by Western <br />Technology of Albuquerque, New Mexico for size distribution. <br />8 <br />