ABSTRACT
Turning now to exit conditions, a high reservoir level at the end of a mild slope (diagram 2(a)) results in an M l backwater curve, merging at the downstream end with the horizontal pool surface. Theoretically, there should be a slight rise in surface level at the exit point equal to the velocity head; in practice there is no head recovery, the entire velocity energy being dissipated in turbulent eddying. A reservoir level below that of normal depth in the channel (diagram 2(b)) produces an M2 drawdown curve which in the limit has a depth that is critical at the exit point. Any further lowering of the reservoir level (diagram 2(c)) has no influence on the surface profile.
