Poster Comment:

Water and sewerage here is expensive, about 1 penny/gal for water and 2 cents/gal for disposal, measured strictly by water input. 33 gals water in/out is a buck.

Back around 2000 I developed a showerhead that was about three times more efficient than what the current requirement at the time was. It started out with a head developed in the 70s that I'd read about in Popular Science back then. It actually works very good. I use them in my house. I think the flow rate is 0.5 gal/min. I think the standard was 1.5 gal/minute back then. The original design was very sophisticated but a little noisy. My modifications quieted it down to a pleasant white noise.

Around 2010 I built a prototype rainwater system for flushing the toilets. It consisted of a 5000 gal Intex rectangular swimming pool in my basement, a shallow well pump and a simple filter to remove gravel from the roof and other chunks of stuff. A second set of plumbing was ran to the two toilets to allow switching between rain or city water by flipping a 3-way valve. That really saved a lot of water and was a really cool project. Rain water is actually very pure. I could've used the rain water for for drinking with a little chlorinating for an emergency scenario.

My water consumption per month is about 1 unit (746 gal) a month. I checked with some buddies/neighbors, theirs averages about 12 units/month.