Friedensreich Hundertwasser

Dear Alex Wade,

I have quite a long experience with humus toilets (7 years) and water purification with plants (5 years).

These are separate items but could be connected. I must say that both, specially the humus toilet, work extremely well. But I must say, too: Only with me and close, very understanding friends. I would never work with anybody with the normal flush and waste mentality. I doubt that low cost composting toilets can be imposed at this stage to average people who are not brought up since their early childhood to love shit and humus and clean water.

I have all the books on humus toilets: “Stop the five gallon flush”, “Toilet papers”, “Good bye to the flush toilet”, American, Swedish, Norwegian manufacturers papers and reviews such as Biocycle, and so on.

I bought a Scandinavian humus toilet by Mullbänk in Sweden, in plastic with flue, vent, electricity, heating bars and a wooden footstep. I had it shipped to New Zealand and Vienna. Many parts broke and I had to ask for new parts and pay lots of duty tax. Then I was not content. I did not like the electricity involved. The humming noise of the vent (why go back to nature and hear constant technological noise like at the dentist’s). Then I did not like the flush design (more like a refrigerator).

I am an artist and suffer from ugliness. Ugly things never work. The clivus is ugly, too. The ugliest part is hidden in the underworld. Then I did not like the flue vent to evacuate air and smell. I went to the roof. It smelled there. I wondered if two million people of a city, like Vienna, would have all compost toilet chimney vents. Then it did not work as the prospectus said. It got too dry when I was absent. When I suddenly got visitors who stayed three weeks it remained dry but the floor was flooded with urine because the liquids rushed through the dry shit and the tray underneath supposed to collect humus was overflowing with smelly urine.

And then I do not like the idea that a humus toilet is expensive and that you have to buy it just like any other technological machine.

So I started to experiment myself with home-made toilets, because I knew the humus toilet must be. It is just the method which is not perfect. For instance, I asked the manufacturer how I could install a humus toilet in a boat, in a yacht (I know boats are polluting harbours and streams). I got no answer. Of course. There is not enough battery charged electricity on board for a Mull Toa, Mullbänk, Bio Loo and so on and no space for a clivus which is almost bigger than a whole ship.

So first I imitated the commercial composting toilets. With flue and kerosene lamp under the container to warm the humus-shit.

Then I found out that, when I cover the kitchen and human waste with a bit of humus, there is no smell, no flies and a flue is not needed. In that context, I read in one of these books on compost toilets that up to 60 % of the heat of the apartment was sucked away through the flue up the vent of the composting toilets! So why do all to retain and store heat, then lose it through the humus toilet! On the other hand, humus is creating heat through the composting process. So, if there is no flue vent chimney, there is no escape of warmth. And you even gain warmth for your room. Normal aeration of the room is all what is needed but no special toilet vent pipe. The toilet container must have aeration from below. Holes underneath for air to let through the mass of humus from below and to drain excess water and urine to a tray underneath.

Urinating remains a problem. But I read an interesting report from a French scientist that higher animals, except birds, have different outlets for liquid and solid wastes. In fact, two treatment plants for liquids and solid wastes which, as we know, involves a lot of energy to separate liquids and solids. The waste treatment plants suffer from the enormous costs involved to separate liquids from solids.

Anyhow, to divide and select the waste into liquids, solids, metals, compost, glass, paper, poisons, plastic, fats and so on is extremely costly and complicated. So: Why put together what nature has separated with extreme wisdom and care? Why urinate and shit into the same container after it has been sorted out with care? There must be a wisdom behind that.

Man uses the toilet several times, about 5 times a day. Only one time is for the solids. Four times it is for liquids. When men and women get rid of their solids, they say they cannot retain their liquids by that occasion. That is questionable but o.k. But the four other times they go to the toilet only to urinate!

A compost toilet without heating system can cope with a small amount of urine. So I was working for a separate system to purify liquid wastes with higher plants after the system of Dr. Käthe Seidel, Krefeld, Germany. She put containers with water plants in gravel in a step formation next to each other and extremely dirty water got cristal clear at the last outlet. She used all kinds of reeds and rushes, especially Schoenoplectus Lacustris (formely named Scirpus Lacustris). In warmer climates and inside the house, I used Cyperus (a big variety including Papyrus). Equisetum Hyemale (winter save grass which works in cold climates, too). Water Hyacints for very warm climates all year round, Swamp Grasses, even floating Water Lilies, etc. There is an enormous variety of water plants which purify water. Practically all plants do this even those which are no water plants.

Plants for indoor water purification: Cyperus Alternifolius and Diffusus, Calla (Zantedeschia), Spathiphyllum, Kalmus (Acorus), many ferns and many others you can try out like tropical swamp plants.

Plants for outdoor water purification: All Reeds, Rushes, Bulrushes, Swamp Grasses, Scirpus Schoenoplectus Lacustris, Water Lilies, Equisetum Hyemale, winter save grass, Juncus Iris, Water Hyacinth, Buttercups, Calla Palustris, Water Plantain, Orontium Aquaticum and so on. You can regulate the water level with flexible water outlets, stiff pipes with bending joints.

The dirt in the water is transformed into plant substance. You should have a big variety of plants. Each plant is fulfilling a different purification job. The cleaner water at the bottom outlet should be poured again into the highest plant tub for the dirty water intake once in a while. Every hour, once a day, once a week, just as you like, as it fits the plants.

By putting water into the top tub you start a cascade running through the containers with the quieting sound of a small waterfall or mountain stream in your own room!

It is like putting on a disk, turning on music, it is playing Bach. Bach means brook or small stream. You will have music for one hour just like with the record player.

The water should splash into the containers creating oxygen and then the inside watertable of each container should drop to the bottom so that the roots of the plants get in contact with air. It is the reciprocal action of water and air which is beneficial to the roots and plants and keeps them healthy and beautiful and good purifying workers.

The idea is: To have a water garden with beautiful plants which serve at the same time a phantastic purpose: To clean all household waste waters including urines.

I think a humus toilet can be designed in such a way that the excess liquids run off into the water plant purification plant. Of course, here again: Average people with a flush and waste mentality will cope badly with a plant purification plant. It needs wisdom, sympathetic understanding of the needs of plants and microbes, if aerobic or anaerobic.

But there is an important point: If you have a beautiful water plant purification plant which is a phantastic little garden of Eden at the same time, you yourself will do everything to feed this water garden well and to keep the plants healthy and beautiful and alive, and you yourself will abstain from throwing detergents and all kinds of poison into the sink and into the bath tub knowing that this will hurt your plants. Just like if you have a dog or a cat which you like, you will not feed them poison because you will want to keep them alive.

So if you have a water plant purification plant, the story does not end with the hole of the toilet and the sink. There is something more beautiful afterwards: A new life, a new beginning and you are committed because you are concerned and you leave the water just as you got it: Clean and you turn your waste into something valuable: Humus. With joy and much pleasure.

This is a very rough sketch of a portable self-made wooden humus toilet without flue nor heating system. Easier to make is a big plastic container with burnt-in big holes underneath (with a heated iron bar). Care has to be taken that you do not shit always on the same spot because then you would create a pyramid build-up of waste and you would use too much humus to cover it.

So a method must be worked out of shitting into the lower moulds, for instance by moving the toilet seat or by turning the whole toilet which is easy with a round plastic container like the big plastic garbage bins, for instance the French poubelles.

There is a method I use to shift the waste without touching it with the shovel and with the toilet paper. Use as little quantity of covering humus as possible. Toilet paper can be stuffed into the humus with the shovel. It is easy and not at all a dirty management. The bad thing about commercial composting toilets is that their seat imitates the flush toilet inasmuch as you should not see your waste. It disappears just like in a flush toilet, with no possibility to cover it with humus correctly. You can just throw in humus and grass clippings and it falls in at random. With the manual or automatic steerer you get all the shit moved around on top again which creates smell and flies inside the commercial composting toilets. This is why I think my flueless toilet is better and more simple and more evident because to cover up your waste with humus is just what nature does. What cats and even dogs do when they are in the open land. What the forest does by dropping leaves on dead bodies and waste. You feel better when you cover waste with humus. Just throwing your waste into the toilet like we do it with all conventional toilets including the composting toilets is not enough. There is something missing. There is still something to do. This is the very pleasant occupation of covering your waste. It takes only one minute. And only then you have a good feeling that something is done and completed. It is like a duty fulfilled.

The toilet seat with the batten across can be put into any position you like on top of the toilet, round or square, and can be hung up on a nail while you cover the waste with humus.

The contents of the humus toilet and the humus to cover the waste must always be kept moist like the forest floor but not dripping wet so that no anaerobic bacteria can establish.

Next to the compost toilet should be a just as large container filled with humus to cover the waste.

When you start a humus toilet, you need the same amount of humus as the contents of the toilet, because you need a lot. But the waste will shrink enormously. First to half the volume, then within 1 to 2 months to 1/3 or 1/4. If you have time, two years, you will witness that waste shrinks to “nothing” (1/10 to 1/20 of its original volume and weight). But, of course, what is filling up the toilet will be the cover-up humus. This is one of the disadvantages of the flueless compost toilet. The other is that it can cope only with a limited amount of liquids. The third is that it takes longer than a heated toilet to turn waste into humus. But this is not a disadvantage. You need more space because while one humus toilet is full and is transforming waste into humus, you must start a new toilet. After 2 to 3 months you can reshovel several times and yo have got new self-made humus to cover up your waste. From now on, you do not need to get humus. You can bring some humus back from where you got it.

Using humus to cover the waste does fill the toilet much quicker, but this is only an apparent setback because, after some time, your waste-humus quantity remains stable with very little excess humus to take away for good use.

1. To put on your grass roof

2. To fill flower pots

3. To bring it secretly at night to a pubic garden

4. To bring it to a farmer

5. To bring it back to the forest floor

To use the humus in the vegetable garden, it needs one more year of composting.

You need at least three big containers, two must have holes underneath for aeration. One should not be upset by the “lost space” the humus toilet takes away from the living space because it is soil, it is humus, a living item which you have got, a bit of the soil of the world and it smells just as good as the forest floor after the rain. This taken space has just as much justification to be occupied as books or furniture, for instance.

To keep the humus moist, you can use a normal hand spray with water. You can use a fly screen. But I found this is not of big use because either you cover the waste better with humus and the flies are gone or you use a non-harmful spray and put the lid on for some minutes.

For the humus toilet, you can use all that rots: Shit, kitchen waste, salad, grass clippings, hair, all sorts of paper, toilet paper, newspaper, package paper, tea leaves, coffee grinds, even rotten meat and cheese and fish (you need more humus to cover more carefully). Not too much ash. No plastic, no poison, no glass, metal or bulky wood. Bones are o.k. though they will not rot within 5 years. Wool is allright, but no plastic fabric, nylon etc. Dust from floor sweeping and the vacuum cleaner is o.k. Pulverized rusty iron is o.k., cigarettes, tabac is o.k., cotton o.k. Only small quantities of fat. Mouldy bread is perfect.

In Vienna, I make experiments with a plant water purification plant under artificial light (halogen lamp, 250 volts). It seems to work. Then the artificial light can be put to a good use: Give life to plants and purification plants (especially in the U.S. A. where people leave the light on all night) and light to people too and have clean water and green plants within apartments even with not much daylight. I can propose curtains consisting of living plants which at the same time have a job of purifying water and air. No work or little studies have been made in this direction, for instance houses for plants in which people can or may live, too, and artificial light for plants of which people can benefit, too. For instance, light is directed onto plants. People have light through the leaves of the foliage.



Written in Kaurinui Valley in April 1982, revised in January 1983.