My family has been living in Melbourne, Australia in the state of Victoria for a few weeks.  It's the middle of winter here (July), and Melbourne is a coastal city.  It is about as far south as you can go on the mainland of the continent (well beyond the tropic of capricorn), and is situated in the eastern part of the country.  The latitude of Melbourne is around 37 degrees.   So one might suppose that it rains a lot here in winter, and indeed it is supposed to.  Well, being from Oregon, I really haven't seen serious rainage yet. The sky greys over nearly every afternoon and looks threatening, but it's mostly bluster and maybe a pavement wetting or a little drizzle here and there.  I've needed an umbrella only twice.  The locals tell me this drought has been going on for over a decade.   Perhaps it is a manifestation of "global warming," really better termed as "global climate change."

The drought is the evil behind the Melbourne fires that happened last summer (January, February) before we came here.  I'm told that the water reserve in Melbourne is down to ten percent, and that normally at this time of year it should be way higher than that.  Water rationing is in effect.  Anyone caught watering with a hose outside of their allotted watering day can be fined.  Watering lawns is prohibited altogether.  Things look green now, but I have a feeling that the place will get a parched look by summer.   Previous rules against having greywater systems have been lifted, and now many people have installed "tanks." 

The lady who owns these digs keeps old bathwater and uses it to flush the toilets. This is fine for her, as she lives alone. We tend to take showers, but we have taken a page from her book and strictly limit them to four minutes. We put the bucket in the shower too and collect what water we can. I've taken to siphoning the rinse water when I wash dishes, and the dishwater as well if it isn't too disgusting.

We've also moved to having a European style wash every second day rather than a full shower. It's actually better for your skin NOT to shower every day, especially if the water is very hot and/or chlorinated.

Our landlady does not have a system in place to recycle laundry rinse water.  However, neither does she have an electric dryer.  Having to hang everything out, or put it on an inside drying rack that takes forever makes you think twice about just tossing your clothes in the wash. 

One of our friends showed us the tank in her back yard.  This tank collects rainwater from the roof that would normally drain into the storm drain.  She may have it plumbed into her washing machine for the rinse water as well.  We're told that up until recently such tanks were illegal, and to the best of my knowledge they still are in the USA due to health concerns. 

Greywater is not without issues, and possible health concerns.  Here are a load of them!  For example, it's fine to use greywater to flush your toilet, but if you plumb it into the toilet tank you will wreck your toilet.  Greywater is not supposed to be kept for long or it will fester.  And, depending on the source of it, it is not to be sprayed or applied to food crops that are eaten raw. 

I am not sure how these backyard tanks that people have avoid keeping the greywater beyond its shelf life of 24 hours, or maybe they add something to it to keep the festering under control. 

The point is, that in the USA I had heard of a few really handy and knowledgeable DIYers having workable greywater systems as long as they didn't get caught, and I once knew a woman with an actual composting toilet.  But in Australia, the water shortage has forced the people to deal with this issue on a large scale, and dealing with it they are.