I can see pumping from a well being expensive. What about capturing rainwater? And once again, storing it in a water-tank. Would require a reasonable annual rainfall and, of course, rain that's safe to drink. Any likelihood of it being polluted? You'd capture the rain from the run-off from your roofs.

I mentioned composting toilets (http://en.wikipedia.org/wiki/Composting_toilet) to vriad as a possible solution. I don't remember noticing the wikipedia entry for them though. There's a lot of links there if you want to build one yourself.