A channel has the irregular shape shown in Fig. P7.3, with a bottom slope of 0.0016 ft/ft.

Question:

A channel has the irregular shape shown in Fig. P7.3, with a bottom slope of 0.0016 ft/ft. The indicated Manning's n values apply to the corresponding areas only. Assuming that Q = Q1 + Q2 + Q3, find the rate of flow in the channel if y1 = 2 ft, y2 = 10 ft, and y3 = 3 ft?