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• <br />Dischazge measurements will be made by wading across the stream with a current meter and <br />wading rod whenever possible. If the depth is less than about 0.3 feet, one of the <br />aforementioned methods will be utilized to measure flow. For the wading method, the <br />midsection method will be used and standazd U.S. Geological Survey procedures will be <br />followed in all note computations (see Buchanan and Somers, 1969). A measuring tape will be <br />extended across the channel and staked perpendiculaz to the direction of flow. If possible, <br />depth and velocity measurements will be made at a minimum of 20 verticals. However, if the <br />stream width is such that the resulting distance between verticals is less than 0.3 feet for the <br />pygmy-type and 0.5 feet for the AA-type current meters, then the number of verticals for the <br />section will be reduced from 20. Depth will be measured using a top setting wading rod and <br />velocity will be measured using either a AA or pygmy type current meter, depending on <br />velocity and depth. In general, the pygmy-type meter will be used for shallow, lower velocity <br />streams and the AA-type meter for deeper, higher velocity streams. The mean velocity in <br />vertical will be determined using the 6/10 method (velocity measured at 0.6 of the depth from <br />the water surface) for depths less than 2 112 feet and the two-point method (velocity measured <br />at 0.2 and 0.8 of the depth from the water surface) for depths greater than 2 1/2 feet. The two <br />point velocity measurements will be avenged to obtain the mean velocity in vertical for the <br />two-point method. Measurements will be recorded on a Discharge measurement Notes form <br />(Figures Bl and B2). <br />