Truths about waterless toilets, of which the most popular type is composting toilets, has been misrepresented.
Notably, the functioning of these toilets and their benefits to the environment has been largely misconceived.
Truth be said, waterless toilets are a novel idea towards reducing the use of water in the disposal of human wastes.
However, some of the explanations usually given about their workings and water saving effects are mythical and inaccurate.
- Misconception about separation of urine from the solid waste
Why is urine separated from the solid wastes in most dry toilets?
Most waterless toilet makers lack a scientific explanation to this. Rather, they prefer to give you an analogy about animals. The analogy goes like this: do animals urinate and defecate at the same time?
Obviously, the answer is no.
However, most animals are quite different from humans in their urination and defection process, save for primates.
Their positioning while undertaking this biological activity is very different. Therefore, this analogy, is not correct.
A more viable answer would be the two are separated for convenient disposal purposes.
When a person excretes, urine makes a bigger chunk of the stuff, about 90%, compared to solid waste.
Also, solid waste occupies less space, especially when dried. Most dry toilets separate the urine from the solid waste once the excreta flow down for storage.
Thereafter, after urine has been drained from the waterless toilet, the taking away of the little solid waste can be done later—after some weeks or months.
- Misconception that waterless toilets are odorless
A waterless toilet that has a malfunction, or which is not well maintained emits odor and attracts flies.
The use of a ventilation system in the waterless toilet takes care of this. For energy-driven composting toilets, a power outage implies having to put up with odors and flies.
Most of us have been sold the idea that waterless toilets are odorless. However, they actually emit odor.
These kinds of toilets have an effective ventilation system in place, and as long as it is working properly, there should no problem with odor.
- Misrepresentation of dry feces as humus
Composting toilets’ sellers rarely tell you where urine will end up.
That aside, it is shocking to note that some sellers promote dried feces as compost.
Myths aside, the solid waste that you remove from your composting toilet’s storage container is not humus.
Scientifically, it becomes difficult for the solid waste to compost after urine has been separated from it.
However, mixing the moist solid waste with bulking materials, such as saw dust, facilitates a curing process.
It is the product of the curing process that most waterless toilet makers and vendors falsely claim to be humus.
- Myth that using urine for irrigating is harmless
When urine is stored for a while in a tank, the organic nitrogen it contains gets converted to ammonium ions.
In form of ammonia, nitrogen only oxidizes when released in nature.
Consequently, dangerous nitrous ions (NO2–), capable of oxidizing to nitrates (NO3–) are formed.
Stored urine, like in waterless toilets, can turn into a concentrated solution of ammonium nitrate. This kind of a solution is akin to chemical fertilizer, and also contains nitrite ions.
Some waterless toilets vendors can tell you the stored urine in the toilet’s system can be used for irrigating plants, especially when diluted with water.
The problem here is the percolation and oxidation of the diluted urine.
In the form of ammonia, (NO4+), nitrogen in the diluted urine finds its way into the water table faster and easily compared to the one in nitrous form (NO2–).
These ammonia ions spread in the soil are oxidized to nitrates (NO3–). Nitrates act in the same manner as a chemical fertilizer on the soil and may harm plants.
This means that urine used in this way may result into nitrate pollution of ground water.
- Misconception that a key advantage of dry toilets is to avoid water pollution
The use of waterless toilets leads to substantial savings on water. That’s a fact; however, the contribution of using waterless toilets to pollution of water may not be very true.
For instance, diluted urine from dry toilets used in irrigation can end up in underground water sources, polluting them. This is not very different from what pit latrines do to ground water.
There is need to be cautious on the reuse of diluted urine from waterless toilets. Perhaps recycling could be helpful.
- Misconception that waterless toilets are easy to maintain
You might have heard that waterless toilets are easy to maintain. That is not very true. The instructions for maintaining any kind of waterless toilet may not be difficult, but they have to be followed meticulously.
And, this is where complications come in, especially if the toilet is shared.
It is not easy to ensure everyone follows all the stipulated instructions—for instance, instructions on separate urination and defection points may be difficult to observe. In addition, instructions on the effective use of bulking material may not be easy to observe.
- Misconception that waterless toilets do not use water
Not every waterless toilet uses water. Some waterless toilets use minimal amounts of water, usually less than four tea cups.
For example, in foam flush toilets, some water is used to ensure the form used for flushing works properly.
- Misconception that waterless toilets are a recent invention
You probably think waterless toilet technology has cropped up due to the increasing scarcity of water in most parts of the world. Wrong.
The first dry toilets were used about a millennium ago; pressure on water resources was limited back then.
The basic archaic waterless toilet had a septic tank beneath the toilet where the waste fell into the space below, without any form of flush. This kind of toilet is a health hazard, and may not be suitable for most modern living areas.
Since then, there have been modifications and improvement of the original basic waterless toilet.
- Misconception that dry toilets are expensive
Although their initial costs may be relatively high, dry toilets are cheaper, particularly in the long-run. Using waterless toilets save lots of water, produce fertilizer, and provide other benefits that outweigh their initial costs.
Waterless toilets are slowly being accepted in most parts of the world, especially in water scarce areas. Most businesses selling them are doing a disservice by telling half-truths about these kinds of innovative toilets.
The half-truths lead to misconceptions about waterless toilet technology, something that deter most people from adopting their use.
Having facts to back claims is important, especially for a utility that can easily become a health hazard or lead to environmental pollution, if not well maintained.
Therefore, correctly explaining everything about waterless toilets can reduce the myths associated with them, and enhance their fast adoption.