On Jun 26, 3:52 pm, Melange wrote:
I dont suppose you'll find too many people who've built an aquaduct on
here!

yes an aquaduct is a good analogy - as for leaks, it wont be on all
the time and as the wall slope there wont be any water sitting on it,
unless the pump is turned on.

Getting a puddle and leak free run over 27` is quite tricky.

I found a product called flexcrete - a cementouse coating, supposed
to water proof damp basements and im told was used to waterproof a
wall that had water cascading down it so should work fine, this is not
an exact science

Take into account flex in the wall as it settles over its length, it
will weigh quite a bit.
So something very flexible and UV resistant is required, not sure that
tanking is ideal for continuous immersion.
Would be tempted to line the channel in butyl and tile the edges in ,
even render over the tiles if it dosen`t suit the look.
If you realy want to use cement, Bondaglass G4 is the evil to use
concrete pond sealer, its moisture curing don`t spray it...

Adam


however what i need help with is, in deciding is "How" to build the
wall taking all the factors i mentioned into account.