I've had both composting toilets and traditional marine toilets.
There are reasons to not install either in favor of the other. The question is how these reasons balance for you, your boat and your intended use.
Having had both, here are the reasons that discourage me from installing a Nature's Head or similar and install a traditional marine head with gravity fed holding tank instead:
1. It's easier to simply open the seacock when appropriate to discharge waste than it is to empty a composting toilet, especially when out cruising.
- The problem in the USA is you can't do that legally in a great many areas.
2. Most composting heads require a vent fan and electric
hook up. A simple, traditional head does not.
- Hook it up to a solar
vent and it pulls any misc odors out of the head compartment with it. I've yet to come across a traditional head that wouldn't benefit from more venting. We took out the pump out fitting and put the solar
vent in it's place.
3. I can install a traditional marine head system more cheaply than the cost of a nature's head. (especially, if I wish to install a holding tank for urine.)
- When you add the fiberglass
surgery and all the misc pieces and parts
, I doubt it.
4. A quart of water introduced into a marine head by accident
is easily flushed away with no consequence. A quart of water introduced into the compost of a composting toilet will make an absolute mess. (Through the vent hose, a hatch
or window left open by crew, etc.)
- We usually leave the lid down so it's highly unlikely. Certainly no worse than landlubbers messing up a traditional unit.
5. Composting heads require one to obtain, carry and replace composting material such as moss, not always easily obtained while cruising.
- In the modern world, peat moss is pretty easy to come by. Others use blocks of shreded coconut husk that comes in small blocks and is broken up and expands.
6. Related to #3, most sailboats already have thru-hulls for traditional heads, but do not already have the vents for composting toilets. (This may or may not be true of your situation.)
7. Most composting heads separate the urine, so one either needs to dispose of a small urine bottle regularly (not necessary with traditional head) or install a separate holding tank for the urine, in which case, you've now to some extent duplicated the very system, many argue a composting head avoids. (A holding tank for urine may be smaller, but now you still have the same need of a through hull
and vented tank that a traditional system requires, as well as most of the same issues that come with installing and maintaining such a system.)
- No, it's still a big advantage. If you want to follow the letter of the law, every few days you can walk a jug of liquid up to ANY shoreside toilet and it's taken care of. If you have a traditional system, you need to up anchor
, find a pumpout station, wait for other boats ahead of you...oops, the pumpout broke...where is another? Then an hour or two later, you get back and your choice spot in the anchorage is taken.
There are or course reasons why one should not install a traditional head and consider a composting head instead, but that was not your question.