Question

Water flows in a rectangular channel in which the bottom width is b = 0.9 (m). The channel lining has an estimated Manning’s of n = 0.017, and the longitudinal slope of the channel is S% = 0.50. If the flowrate is Q = 1696 (L/s) and the depth of flow at a gaging station is Y = 0.22 (m),

1. Calculate the critical depth yc
2. Calculate the normal depth yn
3. Classify the water surface profile.
4. State whether the depth increases or decreases in the downstream direction.
5. Calculate the slope of the water surface at the gaging station.
6. Based on this water surface slope, estimate the depth of flow 100 m downstream of the gaging station.

Answer 1