Yeah I'd think a couple feet deep would probably be fine, not counting the space rocks take up, a 4'x4'x2' hole would hold 239 gallons:http://www.dep.state.pa.us/dep/deputate/waterops/redesign/calculators/volcalchtm.htm
holy crap, check out the new guy with the math skills! Ya know, Tony, you should probably get a pan of some sort to stand in while you shower, and then you can pump that water into your garden after you're done. Yoo could siphon it straight to your 'maters.
I got it. You get a rain barrel...the plastic kind. cut the top off, then cut a door way in to it, leaving the bottom intact, so you have to step up 8 inches or so to step in. (Even put a couple hinges on the door so it swings open and closed.) Double whammy. You have something to catch all the water (put a valve/drain at the bottom/side of the barrel to drain to your garden) AND you have privacy... for a guy, anyways. I'll totally help you with this hippy shit. I'll fire up the sawz-all!!
maybe i could cut the bottom out of it, too, and then attach suspenders.
