Four sets of comprehensive hydraulic and sediment data were obtained during 1961-63 for the Mississippi River at St. Louis at ranges of mean velocity from 3.3 to 5.6 feet per second, of mean depth from 22 to 37 feet, of width from 1,570 to 1,670 feet, of mean water-surface slope from 0.000054 to 0.000109, and of suspended-sediment concentration from 314 to 928 parts per million. The suspended sediment consisted of 9-46 percent sand, 30-46 percent silt, and 20-56 percent clay. The median size of bed material was about 0.42 millimeter for three sets of measurements and about 0.18 millimeter for the other set. A dune bed form was present during all four data-collection periods. Data obtained on consecutive days indicate that the turbulence constant can be computed from either streamflow-measurement notes or from vertical-velocity profiles. Constants computed from streamflow-measurement notes averaged 0.34, and those from vertical-velocity profiles averaged 0.35. The coefficients of vertical distribution of concentration for selected size ranges of suspended sands (expressed as z1, the slope, of the line relating the logarithms of concentration and a depth parameter) plotted against corresponding fall velocities indicate that on the average, the z1's are proportional to about the 0.7 power of the fall velocity. The data also indicate that the relation of z1 to fall velocity may vary with the mean velocity of flow.
Additional Publication Details
USGS Numbered Series
Special sediment investigations Mississippi River at St. Louis, Missouri, 1961-63
Water Supply Paper
U.S. Geological Survey ;
iii, 35 p. :ill., maps (1 fold. in pocket) ;24 cm.