Determine the local change in water surface elevation caused by a 0.2-ft-high obstruction...

Determine the local change in water surface elevation caused by a 0.2-ft-high obstruction in the bottom of a 10-ft-wide rectangular channel on a slope of 0.0005 ft/ft. The rate of flow is 20 cfs and the unobstructed flow depth is 0.9 ft. (See Fig.). Assume no head loss.

Figure