address the issue of the exponential stability (in L2-norm) of the
classical solutions of the linearised Saint-Venant equations for a
channel. We give an explicit sufficient dissipative
condition which guarantees the exponential stability under subcritical
flow conditions without additional assumptions on the size of the
bottom and friction slopes. The stability analysis relies on the same
strict Lyapunov function as in our previous paper (IEEE, 2007).
The special case of a single pool is first treated. Then, the analysis
is extended to the case of the boundary feedback control of a general
channel with a cascade of n pools.