Another thing to consider - a lot of the cruiser guys convert their boats to freshwater flush for exactly this reason.

Basically just means plumbing the head flush intake into your freshwater tank, along with some one-way valves and tubing arrangement to ensure its not possible for the head to back up into your tank. I've been thinking about doing this, since it will also allow me to eliminate one of the seacocks which has various benefits.

I usually take my water tank down to 5 gallons or so for offshore racing just for cleaning up and washing your face - we never drink out of there. I figure if I was ever in a pinch and ran out of fresh water I could always just bring a bucket down.

BTW - while we are on the head subject - anyone see my post here?:

https://j30.us/ubbthreads/ubbthreads.php/topics/12194/Troubleshooting_head_issue.html#Post12194

I hope to troubleshoot this next weekend, if Irene doesn't take out my Charleston based boat first...

-dan