In a rectangular channel, water is flowing at a depth y and a velocity V. At a downstream location, the discharge is suddenly reduced by 60% (i.e., to 40% of the original value), causing a surge to propagate upstream. Determine the depth and velocity behind the surge, and the speed of the surge wave.
(a) y = 1.5 m, V = 1 m/s
(b) y = 5 ft, V = 3 ft/sec