Marine sanitation systems

West Marine offers a good overview of the possible set ups for marine sanitation systems (aka, the head and holding tank).

Interestingly enough, I could not find an article that covered both the traditional options and an age old option that is becoming more popular on boats: the composting toilet. The name is a misnomer, as little to no composting actually happens within the system. The main point of a composting toilet is to separate liquids from solids, which minimizes the odors that we associate with sewage. The urine can be discarded in any toilet, or even overboard in many instances. The feces is mixed with a drying agent, such as coconut fibers, and can be composted or discarded on land or far out to sea.
Whatever you choose, remember we don’t want it in the Bay, follow proper disposal procedures according to local and international laws.
BTW, joker valves are not funny.

Keep safe, keep learning
Tanya Weimer