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<br />DATA FORMAT <br /> <br />The data in the Tabulated Velocity-Profile Data section at the back of <br />this report has been compiled by streamflow-gaging station, by date and gage <br />height, and by the cross-section station number of the vertical. Descriptions <br />of the streamflow-gaging stations, the velocity-profile data, and the flow <br />characteristics for each vertical are presented. Detailed descriptions of the <br />abbreviations used are given at the beginning of the Tabulated Velocity- <br />Profile Data section. <br /> <br />Streamflow-Gaging Station Description <br /> <br />Included in each station description are: Station name and number, gage <br />location, drainage area, average discharge, and gage datum (U.S. Geological <br />Survey, 1981; 1982a; 1982b). Details of the relationship between measurement <br />section location and nearby bridges are presented under the "Measurement Sec- <br />tion Location" subheading. Photographs for higher and lower flows also are <br />presented for each site following its station description. <br /> <br />Velocity-Profile Data <br /> <br />Velocity-profile data includes: total depth, method used to collect the <br />data, observation depth to total depth ratio, observation depth, point <br />velocities recorded by the Price type AA current meter and the Price Model PAA <br />current meter, percent difference between the point velocities of the two <br />current meters, mean velocity for each current meter, ratio of point velocity <br />to appropriate mean velocity, and the percent difference between the two mean <br />velocities in each vertical. Computations of percent difference were computed <br />using the Price Model PAA current meter results as the basis. <br /> <br />Flow Characteristics <br /> <br />'or.ea~h current ~e~er. the flow characteristics computed in each verti- <br />cal include: Velocity-head coefficient; Froude number, est1mated mean veloc- <br />ity by the six-tenths-depth method and by the two-point method, and percent <br />difference between these estimated velocities and the mean velocity computed <br />by the vertical-velocity curve method. The velocity-head coefficient a, was <br />computed by the following formula: <br /> <br />a = l(v3~y) <br />V3y <br /> <br />(1) <br /> <br />Froude number F, was computed as: <br /> <br />F = <br />~gy Cos e/a <br /> <br />V <br /> <br />(2) <br /> <br />All selected stations have slopes less than 6 degrees. Therefore, Cos e, the <br />slope effect correction, is considered equal to 1.0 (Chow, 1959, p. 33). <br /> <br />16 <br />