1

 Channel design based on use of Manning eq. to find normal depth Yo for a
specified discharge.

2

 Flow is fully developed rough turbulent.
 Channel is prismatic, i.e. crosssection is constant along length.
 Flow is uniform, i.e. Sf = S0.
 A0, P0, R0 = f(Y0, geometry).
 Crosssection is fixed boundary.

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5

 Peak value of current Inflow
 hydrograph if one exists.

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11

 Design a trapezoidal channel to carry 2 c.m/s with gradient of 0.3% and
n=0.04
 Design a channel which includes a low flow channel to carry maximum flow
of 12 c.m/s and low flow of 2 c.m/s.
Allow freeboard of 0.3 m. Try for gradient = 0.3%, n=0.04 for
main channel and n=0.02 in low flow channel
