The current boats are now over 45 years old, and must be coming
towards the end of their life. What is going to happen to the derry,
will new boats be built, will it be replaced by a new bridge or
tunnel, or will it simply be closed?

Also, when riding on the 180 bus, between Lewisham and Abbey Wood,
I've noticed two enclosed areas of water just to the west of the
ferry, close to where the spare boat is kept when a single boat
service is operating. Only the Easternmost of these can easily be
seen from the bus, as the other is largely hidden by a building, but
they can both be seen on Google Earth, and there is some sort of
building between them. The water in them seems to be separated from
the river by a concrete wall now, but they look rather like small dry
docks. were they used to maintain the old ferries possibly; they look
about the right size, and if so why were they walled off from the
river? Or were they something completely different?