There is a neoprene coating that can be gotten at AquaticEco.com made by
Herco that comes in white, black or gray, and would act as a liner on the
concrete. Most concrete repair materials using portland cement are to rigid
to permit any movement of the concrete below, which is probably has caused
the concrete to crack initially.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html


"Bill Spohn" wrote in message
...
I have an old cement pond that has started leaking after 60 years. I do
not
want to replace it with a membrane, both because I dislike the appearance
and
because I do not want to disturb either the well established margins or
the
large planted island in the middle of it (it is a large pond maybe 40'
long).

I have tried patching, but this either didn't take or new cracks appeared.

I am thinking along the lines of a layer of reinforcing mesh and a skim
coat of
cement to seal it up again, and while I am at it, I'd like to drop one
section
down a couple of feet to allow a place for the fish to hide and the lilies
to
grow - the pond is fairly shallow.

This chore seesm to fall between the areas of competence of the liner
pondies
and a swimming pool company - no one seems to be geared up for the repair
of
existing ponds, though many will offer to install a new one with membrane,
which is not what I want.

I am prepared to have one more try at patching, if anyone has any
suggestions
for a flexible patching compound that will bond to old concrete. If that
doesn't work, I guess I may have to talk to the swimming pool people :-(

Any brilliant iedeas out there?