My wife finished the shower curtain for our doggy pool shower. I took a quick shower in it this morning and it works, I used about 1.5 gallons of water. I think the dog pool might have a small leak in it so I'll have to sort that out. I was worried that the shower curtain would leak but it seems to be watertight. I still need to put together a drain line so for right now I'll just drag the dog pool out and pour the water into our grey tank.
The shower curtain tends to stick to you; I don't think I'd want to use it on a cold day.
Bruce