Maybe it's just me, but I really don't think that I would personally want to keep my waste around in my little trailer for long periods of time, which would be required for it to break down and "compost" the contents therein. Not to mention adding that extra weight
to the trailer in the form of something I don't feel I need to carry around everywhere I tow it. Every "composting" toilet I have ever used stunk to high heaven. It might be a workable solution in an occasionally used vacation cabin or something similar, but just how would you control the reeking stench from permeating everything in proximity, (and that would include the whole trailer.) I prefer to have a waste tank that I can dump and flush, but to each his own. I don't want my trailer to smell like a State Park outhouse.
Excerpt from an article on the topic:
IS A COMPOSTING TOILET A GOOD IDEA IN AN RV?
There is a growing interest in using composting toilets in RVs and boats instead of conventionally plumbed flushable RV toilets and marine heads, and we have received lots of inquiries from people who want to live an off-the-grid boondocking
lifestyle, like we do, asking us if they should install a compost toilet in their RV.
Composting toilets are flushless and more or less “odorless” systems that can compost human waste into dirt for planting flowers in a garden, if the poop and pee are left in the toilet long enough. Unfortunately it takes SEVERAL MONTHS for a composting toilet to compost human waste into dirt. What do you do with it in the meantime?
Composting toilets are fabulous in a cabin or a house with a compost pile out back. Simply empty the toilet into the compost pile and watch it magically transform into beautiful gardening dirt! Compost toilets are wonderful for part-time RVers who have a compost pit in the yard where they can dump the toilet and actually compost the poop into dirt. Composting toilets are also great for part-time RV and boating use if the owner uses the RV or boat for a few weeks and then puts it in storage for months at a time, allowing the feces in the toilet to compost completely during that time. Composting toilets are COMPLICATED for full-time RV use! WHERE you are going to DUMP YOUR POOP when the toilet gets FULL?
A kitchen sized trash bag full of human poop is not something that is easy to dispose of LEGALLY, and most campers don’t want to camp in a place where someone has left a bag of it behind. If you have not done much boondocking
yet, it may come as a shock that many dispersed campsites on public land are filled with trash, much of it extremely disgusting (used diapers, used condoms, used toilet paper, you name it). We routinely fill a grocery bag or two with trash when we set up camp on America’s public lands. We don’t want to be hauling out other campers’ poop too! Digging a hole big enough to bury a kitchen bag of poop properly (at least 6″ below the surface) will take a lot of work, especially in places like the western states where the ground can be as hard as cement. Also, poop from an RV composting toilet is TOO THICK to stuff down an RV dump station sewer pipe. Dumping conventional RV holding tanks at an RV dump station takes 10 minutes and it puts the poop in the sewer or in a septic system where it belongs! Composting toilets are very expensive. Two of the more popular ones are manufactured by Nature’s Head and C-Head.
When Do Composting Toilets Make Sense in an RV or Boat? The big question for anyone considering one of these toilets is: will your waste stay in the toilet long enough — that is, for enough months — that it can be composted into dirt as the system is designed to do? If not, what are you going to do with it?
When should I empty it? It is best to allow the solids to decompose before emptying your toilet. The longer you wait before emptying your toilet, the nicer the job will be. Many boaters will leave the solid wastes in the toilet over the winter and empty it in the spring.
Where should I empty it? “Ideally, the compost section would be emptied in a compost pile or bin. If traveling, it can be disposed of in a bag or buried.”
The usefulness and convenience of these toilets as compared to traditional RV toilets and heads depends entirely on how you use your RV or boat. Do you put your boat or RV in storage for months at a time? Do you boondock in remote areas far from other people? Do you stay in campgrounds and RV parks? Can you easily take your boat three miles offshore in the ocean where it is legal to dump human waste overboard, or is your boat on an inland waterway? Do you know of a public composting bin or composting company located near your home, or do you keep a compost pile in your back yard?
Urine vs. Feces and Composting Versus Disposal: Composting toilets separate the urine and the feces to reduce the odor. To get some great dirt for planting, simply leave the feces waste in the toilet while the RV or boat is in storage, or put it in a public Composting Bin or in your own compost pile in your yard. Unfortunately, whether the feces has time to compost in the toilet or not, the urine waste that the toilet separates out needs to be disposed of every few days. This frequent disposal of the urine may be the deciding factor against composting toilets for many RVers and boaters.
Disposing of the Urine: Compost toilets are built with a removable container that you can carry to a public restroom (or elsewhere) to flush the urine down an ordinary toilet. (Note that by doing this you haven’t saved the planet’s water. Drinking water is still going down the toilet, just not down YOUR toilet!). The C-head composting toilet is designed so you can use commonly available one-gallon plastic water jugs to dispose of the urine. Finding an appropriate place to dispose of the urine every other day or so is something to think about. A gallon of urine poured out in the boondocks fouls the land much more intensely than a cup of pee on a bush. For boondockers staying in one place for several weeks, the walk to an appropriately remote spot that won’t foul the area for future campers at that site will get longer and longer, since you obviously don’t want to keep dumping these gallons of urine in the same place over and over.
Disposing of the Feces: In addition, unless the RV or boat is put in storage for six months at a time so the contents of the toilet can compost completely, the feces waste will also need to be disposed of before it is fully composted, likely after about two weeks to a month. At that point the material still resembles feces and it has a cookie dough-like texture and it is not odor free. The manufacturer recommendation is to dump the material in a composting bin, because there are legal ramifications with the disposal of biological waste. Boats that can get three miles out to sea can legally dump that waste overboard. For boats on inland waterways and for full-time RVers, finding a public composting bin will be very difficult (we’ve never seen one in our travels), so you will need to find an alternative way to dump the poop. Transferring the feces into an RV (or marine) dump drain is difficult because it is so thick. While boondocking
, you can use a shovel to dig a deep hole and bury it.
On public land, that is, the National Forests and BLM land, the legal requirement for disposal of human waste is to dig a hole and bury the feces under at least 6 inches of soil. This is not too hard to accomplish in places where the ground is soft. However, it is very difficult in many of the western states where the ground is extremely hard and is often like cement. Using a pick-axe will help. One way to soften hard ground is to soak it with water or dig the hole after a rain storm. Of course, one of the primary reasons for using a composting toilet is to save water, so soaking the ground with your precious water supply makes little sense. Also, you can have a six month wait for rain in the western states.
In most places the local laws allow for the dumping of adult diapers, kitty litter boxes, and individual baggies of dog poop (that owners pick up while walking their dogs) into conventional dumpsters. So, the common method for RVers is to bag the feces and put it in a dumpster. Simply remove the feces container from the toilet, put a kitchen garbage bag over it and dump the feces into the bag with a few good strong shakes. One manufacturer recommends sterilizing the feces with bleach before bagging and dumping. Of course, a big kitchen bag of smelly poop is not the nicest thing to put in a public dumpster, especially for the next person who raises the lid to dump their trash.
What about the Grey Water Tank? For RVers, there is still the grey tank to contend with. While boondocking in remote areas, it is common practice for RVers to discharge the grey water on a thirsty bush or patch of grass and then to refill the fresh water tanks from jerry jugs. However, if you have a composting toilet and the grey tank fills up before you can get to a remote area, you will have to go to an RV dump station to dump the grey tank, which defeats one of the main purposes of having a composting toilet.
Do You Save A Lot of Fresh Water with a Composting Toilet? You will use less fresh water with a composting toilet than with a conventional flush toilet because no fresh water is wasted in flushing. However, not all that much fresh water really gets flushed down the toilet with a conventional RV toilet. In our experience, using a gravity-fed, non-electric flush toilet, only about 10% of our fresh water gets flushed down our toilet, or about 7 gallons every two weeks (just over a jerry jug’s worth). About 60% of our fresh water use is for showers and 30% is for dishes in the kitchen and for washing our hands and faces and brushing our teeth at the bathroom vanity (we drink bottled water). If the RV toilet is an electric head with a macerator, as is found in higher-end motorhomes, more fresh water will be used for flushing — perhaps 15% of the total fresh water capacity. So, although a composting toilet will save some fresh water, it won’t be saving enough to make a big difference.
How Does a Composting Toilet Affect Resale Value of an RV or Boat? Another thing to consider is that a composting toilet in an RV or boat will most likely negatively impact its resale value. You probably aren’t thinking about selling your RV or boat right now, but the day will come when you hope to get a good price for it. However, because many people will not want to buy an RV or boat that has a composting toilet in it, you may find a lot fewer prospective buyers. You can hang onto the parts you remove when you install your composting toilet, so you can reinstall them at resale time, but where are you going to keep those parts in the meantime? Do you really want to go through that extra labor of installing a composting toilet and then removing it later?
Should You Install a Composting Toilet in Your RV? To us, the high cost of purchasing a composting toilet, the expense and labor of retrofitting a composting toilet into the bathroom, and the mess and difficulty of dealing with the waste, all make the whole idea of a composting toilet seem totally inappropriate for RVing or boating. In our minds, the only situation where a composting toilet makes sense is for people that use their RV or boat for a few weeks and then put it in storage for six months or more at a time, giving the toilet a chance to compost the human waste into dirt as it is designed to do. For full-time RVers, a composting toilet doesn’t make any sense at all.
In the end, since an RV composting toilet will likely require you to dispose of your non-composted human waste by burying it, flushing it down public toilets or putting it in public dumpsters, a much less expensive and much simpler but very similar alternative would be to get a little portable camping toilet. The huge advantage of a portable camping toilet over an RV composting toilet is that it is less than 1/10 of the cost!