In message , Aidan Stanger
writes

Actually operating boat services on tidal rivers is very easy! The
(small) CityCat on the Brisbane river, and (large) Sydney ferries on the
Paramatta River do it all the time.

Nevertheless, the amount of infrastructure needed for the piers and
pontoons on such services is very, very much greater than that needed
for the Venice ACTV network, which uses little more than floating bus
shelters.

Docking is another consideration - where there is no tide to speak of, a
waterbus can be docked in seconds by one person and held on a single
figure-of-eight rope. Docking on the Thames invariably takes 2-3 minutes
at each stop and needs several staff, thus adding considerably to time
and cost.

--
Paul Terry