>I am pretty sure if you had to get your water from one of these devices you would not be using it to flush toilets or other non-essential use.

Are you suggesting that toilets, showers, washing machines use salt water?

If their toilets used clean water, then I have a much more efficient way to produce clean water : drink from the toilet and shit in a hot house.

Is there a problem with flushing a toilet with salt water?

Offhand I'd say that you are doubling the plumbing system plus you are using a much more corrosive fluid.

It would be an interesting experiment, since toilets use a great deal of water. Take a beach town, build a separate pressure water and sewer system, see if it's worth it. It's certainly more complicated than a sailboat's set up.

From Wikipedia:

> Drinking water, also known as potable water, is water that is safe to drink or use for food preparation.

40-50L per day would seem to about cover one person's essential uses of potable water.