Can slaked lime be made waterproof?

Hi,

I'm looking for not too toxic ways of building waterproof containers and I need a waterproof mix/mortar . Can this be done with slaked lime? I read somewhere that the ancient Romans built canals in slaked lime, but I would need a kind of recipe.

I'm looking at doing two things in the near future:
- Build a raised bed (hip height) with round river stones (need something to hold them together) with root cellar function on one side (on top of the root cupboard I will of necessity only plant shallow rooted plants or seedlings maybe)
- Build a series of interconnected water purification basins

I'll be happy with any suggestions you can give!