DesignEducationHow toPopulation

Humanure Is No Laughing Matter, Part 2: The Easy-Does-It Instructions

So, it would seem with one mountain of humanure now behind us—that, without a doubt, we should be composting human feces and urine (and, some would say, will eventually have no real choice in the matter)—it is now time to address exactly how this movement should begin. For those who missed last week’s article, please feel free to hit the pause button for a recap or simply press on knowing that we adequately explained that bathroom composting is a world must-do.

In urban settlements, the cities proper, where back gardens don’t exist and life is more or less walled-in, there are ready-made composting toilets suitable for the run-of-the-mill, high-rise apartment. These are stand alone, often electrically run, designs that deal with excrement right away, typically drying it out and leaving behind but of miniscule fraction of what originally exited. This, of course, works fine and is a viable solution for urban, suburban and even rural situations.

However, this article is meant for those of us who are in less urban circumstances. We are talking the ¼ acre or more crew with compost bins of our own, a penchant for growing edible landscapes, and a realized pursuit, at least in part, of the agricultural side of self-sufficiency. For those folks, missing out on humanure compost is something that can (and should) be remedied ASAP and easily.

Suburban Vegetable Garden Run Off Humanure (Courtesy of SuSanA Secretariat)
Suburban Vegetable Garden Run Off Humanure (Courtesy of SuSanA Secretariat)

The One-Paragraph Revision of Why It’s the Time for Change

Human feces and urine are valuable cycles within the natural system. By taking them out of it via flush toilets, we are leaving the land depleted of useful nutrients, essentially taking out the soil-replenishing part of the garden to mouth to soil back to the garden circle. We are also wasting a massive amount of fresh water and seriously polluting our landscapes and water sources, including lakes, rivers, oceans, and underground springs. It’s a practice so unsustainable that some authors have claimed to be completely devoid of humor regarding the current sewage system, unable to even muster one fart or feces joke in their pleas for the widespread public appropriation of more ecological practices (especially from those who peruse the pages of permaculture websites).

The One-Paragraph Explanation of Where It Might Best Begin

Urban environments, as they now stand, are set up poorly for composting, but in suburban and rural settings, there is a real opportunity to effect systematic changes on a personal level. In other words, in a city, it’s hard to set up a compost heap, let alone fill it with feces, but in the suburbs, space comes at less of a premium and many people (again, those perusing the pages of permaculture websites) are already composting and gardening. In the country, forget about it: Only a fool isn’t growing some food and spreading a piles of decomposed organic material around. Cities are currently hung up on sewers and water treatment plants, but this sort of destructive and wasteful method can’t remain much longer. Put simply, less cosmopolitan sources might be where this tidbit of green enlightenment originates, and so be it. Time will tell, but it’s going to have to happen one way or another.

The One-Paragraph Complaint on How Septic Tanks Fail Us, Too

Unlike the city, often country and suburban homes are hooked up to personal septic tanks, which in theory would cause much less of a problem than the municipal congregation of crap. However, septic systems are still troubling. In essence, without some serious chemical intervention (never a good thing), they do not do away with those human pathogens everyone seems so worried about with regards to human “waste” products. Rather, septic tanks store them all, allowing polluted water—now with pathogens and chemicals—to seep into the landscape, possibly reaching and fouling fresh water sources en route to letting nature finish filtering it. Ultimately, the septic tank gets full of solids then must be emptied such that all of the pathogen and/or chemically rich sludge (that’s what it’s called) must still be dealt with somehow and somewhere. The long and short of it is that they are a smaller version of the same water treatment problem.

Classy Indoor Dry Composting Toilet System (Courtesy of SuSanA Secretariat)
Classy Indoor Dry Composting Toilet System (Courtesy of SuSanA Secretariat)

The One-Paragraph Account of Why Dry Composting Toilets Are Better

However, with dry composting toilets, the wastewater element of going to the bathroom is effectively eliminated. No fresh water is wasted to get rid of the excretions, and no contaminated water needs to be cleaned afterwards. We are back to the original mess we’ve created: feces and urine, which are unavoidable and completely natural. While they do have the potential to be dangerous and have contributed to the spread of disease, dry composting toilets address all of that much more effectively and constructively than most current industrialized systems. The elevated temperature of compost, as well as the time it’s given to decompose, natural annihilates the problematic elements while rendering an amazingly beneficial product for the planet: rich compost.

The One-Paragraph Guide to How Dry Composting Toilets Work

Other than the pathogens, most people worry extensively about the smell of dry composting toilets, but in reality, it’s not such an issue. Just like we do with composting bins, when we add something that might rot and cause a stink (typically nitrogen-rich), we cover it with something to absorb the smell (typically a carbon element). Dry composting toilets work the same way. Instead of flushing, we cover with carbon: this can be sawdust, chopped up straw, grain husks, etc. The carbon part soaks up the smell and balances the nitrogen—feces and urine—for better composting. Then, just like with cold compost, this is collected until it reaches a sufficient size (at least a cubic meter) and is capped off, left unturned, until decomposed completely, generally about year. At this point, it’s rich, clean-smelling compost, free of pathogens and with no resemblance to its excreted origins.

A Funky Eco-Outhouse Composting Toilet (Courtesy of SuSanA Secretariat)
A Funky Eco-Outhouse Composting Toilet (Courtesy of SuSanA Secretariat)

The Two Commonly Utilized Options For Dry Composting Humanure

Two different types of receptacles are commonly used for composting humanure. One is conveniently small, portable and allows for using the toilet in the home, much the same as modern bathrooms now. For this version, the humanure (and urine) is collected in small receptacle (typically a five-gallon bucket), covered and carried to the composting heap, where it will decompose and sanitize. The other, which many affectionately call the thunderbox, is essentially a raised outhouse with two chambers beneath it. The compost is collected (on the surface of the ground, not a hole) in one chamber and simply rots in situ as the other chamber is being filled. This version, while less convenient in location, means composters never need deal with the humanure until it is completely converted to compost. The dry composting life is not without its options.

• The Indoor System

Pooping in a bucket, of course, sounds a bit too rudimentary for many, but this type of dry composting toilet can be quite attractively built. Generally, the buckets are hidden beneath crafted wooden seats or benches that have typical toilet seats atop them and often a place to store an extra bucket (either full with a lid on or empty and awaiting use) out of sight. The bucket gets a layer of carbon material, sawdust being the most popular, at the bottom, and after every use, a new cover layer is added until it is full.

When both buckets are full, the humanure is taken out to a compost bin, about 1.5 m X 1.5m X 1 m (high), away from the house. A hole is made in the center of the compost heap. The buckets are emptied such that the contents are completely bordered on all sides. Then, it is covered over with more carbon material. Once this compost bin is full, (It can also handle food scraps, trimmings and all that a normal bin holds), a year being the ideal building time, it is left to rest unturned for an additional year. At this point, it’s compost and not fecal matter. In the meantime, another bin is filled.

This is obviously a better choice for suburban practitioners and also works well for rural homesteaders that still enjoy the convenience of in-home bowel and bladder evacuation. The humanure can just become part of the regular organic matter composting system. Many people still worry pathogens, but the system does work. For those with reservations, make a third composting bin and give it another year to cure, or simply use the compost for fruit trees only.

Composting Toilet Block with Rotating Barrels (Courtesy of United Diversity)
Composting Toilet Block with Rotating Barrels (Courtesy of United Diversity)

• The Outhouse System

The main issue with the thunderbox is that it doesn’t really work outside of truly rural settings. Most suburban neighborhoods wouldn’t tolerate the neighbor having an outhouse, but they’d likely have little to say about a compost bin (as is used with the indoor system). However, the thunderbox works every bit as well and has the plus side of not needing to handle buckets of crap on a weekly basis.

Again, this system starts with a raised outhouse, underneath of which there are two chambers, essentially the same size compost bins as used in the indoor system. The floor of the outhouse has two holes, one above each chamber. The active chamber has the toilet above it, and the resting chamber’s hole is covered over with a lid or board. After each use, a person drops a good scoop of carbon material into the hole. When the chamber is full, it is left to rest for a year while the other one is filled.

The composting chambers beneath the thunderbox are more or less well-situated bins, much the same as any other cold compost heap. They can be fed kitchen scraps, yard clippings and whatever else. If the smell is noticeable, simply add more carbon material to absorb the issue. It never needs to be turned. It just needs sufficient time to let nature do its thing, and that’s what’s going to make all those pathogens disappear.

There are many reasons why people are afraid of their own feces, but suffice it to say, that, as with many modern fears, these are also largely misplaced. It doesn’t require rocket science to handle the situation cleanly, effectively and productively. What does require massive amounts of mental and physical energy is adding water to the mix and then trying to clean that water, which in the end leaves us with not just the human elements but also truckloads of chemicals. Dry composting simply makes more sense, and there are no specialists, pricey plumbers or water treatment set-ups necessary to keep cycling smoothly. That’s good design.

Once more, serious thanks is due to Joseph Jenkins for his great, extensive book The Humanure Handbook, as well as various other sources from which bits and pieces of information and inspiration have been cultivated.

Feature Image: Where Does the Sewage Go? (Courtesy of Graeme Law)

Jonathon Engels

The financially unfortunate combination of travel enthusiast, freelance writer, and vegan gardener, Jonathon Engels whittled and whistled himself into a life that gives him cause to continually scribble about it. He has lived as an expat for over a decade, worked in nearly a dozen countries, and visited dozens of others in the meantime, subjecting the planet to a fiery mix of permaculture, music, and plant-based cooking. More of his work can be found at Jonathon Engels: A Life About.


  1. There are pathogen dangers downplayed by this argument. Runoff can be a serious concern where drinking water or food crops stand downhill. This can be mitigated with proper placement of the compost bin, but one should also consider potential flooding as a risk.

    Also, the numbers used for volume estimates in this article are quite low. Maybe a bucket per week and a bin per year works for a person living alone but, in reality, the volume is much higher. A family with an active social life should increase those estimates by 3x or more, especially if the same system is used for green compost.

    I’m sharing these things from my experience building and maintaining humanure facilities.

    1. Piper, a properly designed humanure compost bin works like a sponge. Differently from what this article states, there is no reason to separate feces and urine. One is bacteria, one is nutritious. By separating our deposits, we are either, 1) adding work to what should be easy (if we later pour on the urine) or, 2) the compost is not going to be nutritionally balanced. Deposits should go into a toilet as one needs to use the bathroom and fully covered with a material like partially rotted sawdust. Other materials include ruined (chopped) straw or coconut coir and ground hemp, but there are many materials that will work. Small particles are best. There will be no smell as long as the “pile” in the toilet is fully covered. The bottom of the compost bin should be dug, concave-shaped soil, not concrete, not very deep in the middle, and certainly not level. Whatever material is chosen to cover the bottom (like straw) should be about half as deep as the bin, and the sides should be constructed with thick “chips” of straw, pine needles, or whatever carbon-based material is used. All deposits should be placed in the center of the compost bin so that all outside-sides remain fully dry. Food scraps, dead animals, meats, cooking oils, etc., can be placed under the toilet contents. Placing of materials in the middle is critical to creating the sponge-like quality of the compost bin. Of course, there is a risk if the area floods, but if we want to make humanure, common sense dictates that we be mindful of where we place compost bins in the first place. Totally agree that the volume is way off in this article.

      To the writer of this piece, it is important to read Jenkins book if you are going to give him credit or thank him for anything you’ve put forth. Your article misrepresents his work, which misleads those who are trying to learn how to make and use humanure. That does a disservice to students and to Jenkins.

  2. Contaminated water or run off in a system set up like in the book Humanure isn’t a problem and has been proven world wide. Non thought out systems or the well abused outhouse pit WILL lead to future problems.

  3. I’ve been using a dry composting loo system for four years now.
    The above comments re runoff are exaggerated. I have a small (maybe 500cumm) transpiration pit that handles runoff, honestly hardly anything goes into it. 90% of the accumulated waste is paper and wood shavings, it absorbs most of the liquids.
    I have six bins that I rotate so they get about six months composting time. When we need a new bin I dig a shallow pit (half a metre deep max) dump a bin in, toss some soil on top and add a tree, I have a pretty impressive orchard.
    The biggest issue I’ve had so far is the the compost being too dry. To solve that when I finish a bin, I close off the outlet tap and add about 10ltrs of water with compost accelerator added.
    I came here looking for info on whether I could plant a pumpkin on the next load but you really don’t have any concrete info

  4. Can you bake your humanure in buckets instead of adding it to a large pile? If so do the buckets get sealed off with their lid or do they near air?

  5. Love this article. I agree that the volume estimates are far too low. I live off grid with my family of 3. We generate about 4 buckets of humanure and one bucket of food scraps per week. This amount may be slightly less for people who go to work or school outside the home. We use sawdust as a cover material. In one year we have filled a 3 bin pallet system. We live in a climate with 4 seasons. Our piles froze this winter and are still dormant. We are still filling the 3rd bin, but I anticipate it will be full in another month or two. This is a huge amount of compost. The piles heat to 120° plus. They don’t shrink as much as I would have thought. This is something to consider when you’re starting out. We will need to build an additional bin in order to allow the compost time to mature. Also, if you construct and maintain your bins properly there are no issues with leaching. The pile acts as a sponge and the heat helps the pile evaporate excess water.

  6. I really appreciate the instructional information that is presented here. My one question ,and one I have not been able to find an answer for,is do you water the bin while it is aging?
    I live in a dry Arizona environment.
    Thank you for any advice

    1. Hello Janice. I had a humanure composting system for several years in Southern California. Because of the dryness, yes, the compost needed additional water. Bacteria can’t do their job without sufficient moisture. Please refer to Joseph Jenkins does a great job in his book answering this question, and practically all others.

Leave a Reply

Your email address will not be published. Required fields are marked *

Related Articles

Check Also
Back to top button