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<br />of the equations (2) and (3) provided in reference (1). The computation process for a <br />three section slope-area is fairly complicated. For that reason the solution method will <br />be detailed in an example problem <br /> <br />Equation for 3 section slope-area <br /> <br />(2) <br /> <br />General equation for slope-area <br /> <br />(3) <br /> <br />Where: <br /> <br />Q = Computed discharge in cfs. <br />n = The total number of cross section used. <br />K = The conveyance of a cross section. <br />h = The difference in elevation between the upstream and downstream <br />cross section's water surface elevation. <br />L (0-1)-n = The reach length between adjacent cross sections, <br />a = Cross section area. <br />g = Acceleration due to gravity or 32.2 ftlsec2. <br />ex = Velocity head coefficient as defined in Equation (5). <br />k = A coefficient of expansion and contraction. <br /> <br />5.5. THREE SECTION SLOPE-AREA EXAMPLE PROBLEM. <br /> <br />Example computations for a slope-area measurement obtained by the Omaha District <br />on Seal Slough at Lincoln, Nebraska in September 1989 are presented here to illustrate <br />the computation of a 3 section slope-area. The example will begin with the discharge <br />computation. It is assumed that the preliminary steps of refining the field survey notes, <br />computing the length between cross sections, the reach fall and the Manning's properties <br />have been completed before this step. Those values will be listed as the "given" for the <br />example. <br /> <br />1-8 <br />