A stream bed has a rectangular cross section 5 m wide and a slope of 0.0002 m/m. The rate of flow in the stream is 8.75 m3/s. A dam is built across the steam, causing the water surface to rise to 2.5 m just upstream of the dam. (See Fig. P7.15). Using the step method illustrated in Example 7.5, determine the water surface profile upstream of the dam to a point where y = yn ( 0.1 m. Assume n = 0.015. How far upstream does this point occur?
Fist we must find yn. Assume n = 0.015.