On Fri, 20 Apr 2012 03:46:06 -0700, Kelvin Kersey wrote:

Hi all. I live in a drought area and my (Victorian) house has a large
underground cistern for collecting rainwater. It is empty and has not
been used for many years (I suppose since mains water was installed) and
I'm wondering whether I could use it again by diverting drainpipes or
just the overflow from water butts.

Possibly. I expect it's solid enough - a space filled with water
shouldn't cuse any more problems than a space filled with air. Who knows
what is decaying down there or if there are cracks in the walls through
which stuff might leak - I'd say let it fill up, then get the water
tested before using any of it (and possibly get it tested again
periodically for a couple of years just to make sure nothing nasty's
getting in there)

cheers

Jules