The overflow spillway of Example 8.2 discharges into a side-channel spillway ( n = 0. 01 3) with a horizontal bottom slope. The wall opposite the overflow spillway crest is vertical, and the depth of water at the exit end of the side channel is critical depth. Determine the depth of water at the beginning (upstream end) of the channel using 20-m ( Δx ) increments. The width of the channel bottom is l 0 m.