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<br />36 <br /> <br />. <br /> <br />Chapter IV <br />DATA AND RESULTS <br /> <br />. <br /> <br />. <br /> <br />Comparison with Observed Flows <br /> <br />The PR~FILE program was checked by solving for water surface <br /> <br />profiles on a steep mountain stream. The average gradient of the <br /> <br />stream was 0.01 and the discharge ranged from 200 to 14,000 cfs. <br />Field data were taken when flows were near 3,000, 6,000 and 14,000 cfs. <br /> <br />Data included longitudinal stationing along the thalweg and cross- <br /> <br />sectional data for approximately 20,000 feet. Cross-sectional data <br /> <br />were taken at 500-foot intervals along the thalweg. Most of this <br /> <br />data was extracted from close-interval contour maps and checked by <br /> <br /> <br />several field sections. the foregoing data were supplied through the <br /> <br /> <br />courtesy of Mr. A. F. Huggins, of Barton, Stoddard, Milhollin and <br /> <br /> <br />Higgins, Boise, Ldaho. Basic data on bed roughness were supplied <br /> <br />by Drs. D. B. Simons and E. V. Richardson of Colorado State University. <br /> <br />An actual profile of the stream for a flow near 6,000 cfs was <br /> <br />traced by use of a series of sawdust ribbons placed at intervals along <br /> <br />both banks. The 6,000 cfs flow was a relative peak so that elevations <br /> <br />at the lowest points of the sawdust ribbons were measured after the <br /> <br />peak had passed. Discharge was measured at a gauging station immedi- <br />ately upstream from the reach. Three different programs were then <br /> <br />applied to the observed flow in the reach. The objective was to see <br /> <br />which program could adequately describe the observed profile and <br /> <br />other flow parameters. <br /> <br />The USGS program, as previously mentioned, proved suitable <br />for flows with a Froude number not exceeding about 0.7. For that <br /> <br />. <br /> <br />. <br />