Converting a "classic" outhouse into a proper humanure composting operation

In vicinity of my property there are some old summer cabins and near each of these there is an old outhouse hidden somewhere in the woods. It is usually something like on a picture below.



It usually stands above a deep (over 2 meters) hole in the ground  that usually contains dozens of years of deposits. Since it is placed on very sandy soil, it never fills up. I think it might have negative impact on ground water quality.

My question is how to convert such outhouse into a proper humanure composting operation. Or perhaps it is better to build a new one from the scratch in a different place? How to speed up composting of what's left in the hole?

Hi Richard;
Yup , got one of those at our place. A TWO holer even!  We had them back east in new england and I have one here in Montana.  
Standard practice is keep a bag of lime with scooper. Make a deposit in the hole ... pour a scoop of lime on top., to aid decomposition. Works so well that new holes are not often needed.

The problem I see is: how would yoube able to get the humanure out of the whole? Would you move the structure and then dig it out?
I personally am planning to build a double chamber compost toilet above ground, with doors to access the humanure once it's ready.

I can remember reading in the Humanure Handbook, that traditional out houses can result in groundwater contamination, but the depth often mentioned is "6 ft". But I also read that many people dig pits for composting, but usually mention "3 ft". So I'm now wondering how much of the difference is that a 3 ft hole gets sufficient air exchange either due to worms, local plant roots, or the nature of the soil (for example, we've got a thin layer of soil on top of heavy clay subsoil and I'm not convinced 3 ft would be safe on my particular soil)? So how much of the issue is: A) not enough absorbent brown material at the bottom, B) lack of oxygen at the bottom and/or C) lack of plant roots to absorb the nutrients at the bottom before they leach to where we don't want them?

Would the solution to this problem be to simply jack up the outhouse onto stilts, fence in the base so you now have an "above ground" compost heap, add lots of brown organic matter, and maybe plant some sort of heavy feeding plants around the base? (And of course, add stairs or a ladder!)

Those big trees in your picture have probably tapped into what's been in the hole/soil all this time.  That helps keep the ground water from being contaminated.   Growing medium sized trees next to the outhouse will send roots into the deposits.  Large trees might be a lot of take care of or control, so even large shrubs that won't endanger the outhouse building will help use up what's there.

You can also add your local worms to the hole and let them work on it.  They are excellent at taking care of everything in such a location.  Find 50 or so or your own worms, and put them to work.  They will multiply and just love it.  

Not sure how many people you intend to have using these outhouses, but if it's only a few, and if your water source is not in line with the outhouses, the soil critters/worms and plants should handle it.

Richard Gorny wrote:In vicinity of my property there are some old summer cabins and near each of these there is an old outhouse hidden somewhere in the woods. It is usually something like on a picture below.



It usually stands above a deep (over 2 meters) hole in the ground  that usually contains dozens of years of deposits. Since it is placed on very sandy soil, it never fills up. I think it might have negative impact on ground water quality.

My question is how to convert such outhouse into a proper humanure composting operation. Or perhaps it is better to build a new one from the scratch in a different place? How to speed up composting of what's left in the hole?

Hi Richard,

Here's an example of a compost toilet in what some would consider an outhouse. Although this is in Africa, this scenario is also used throughout the US. In Africa they haven't wrapped their brains around the idea that toilets can be indoors, as compost toilets can and should be. There's no point in having a toilet in an outbuilding if where you need it is indoors. The Loveable Loo Overview video shows a compost toilet in an outhouse on a site where no alternative location is available.

Africa outhouse compost toilet:  

Loveable Loo (compost toilet) Overview:  

Joe Jenkins

Even the LovelableLoo video says it's not a composting toilet, it's just a "collection device" for composting elsewhere.

The threads at this site should probably make a bigger distinction among composting in

(1) composting toilet with a tank,

(2) bucket system that is composted out of doors

(3) A cesspit dug into the ground with no container, which is what this thread is talking about.

The intended topic of this post was:

how to convert such outhouse into a proper humanure composting operation

Seems like the biggest hurdle for conversion of one of these is going to be extracting the finished product. I can think of some ways you could mount the structure up off the ground to be able to make use of the deposits but as long as its going into a deep hole in the ground I think you're kinda stuck with it

There is a certain joy in stripping clothing out in the sunshine and enjoying the view while you respond to Mother Nature's call.  But that's only in reasonably good weather and not in the middle of the night.  Put your main collector inside your house!

Richard Gorny wrote:The intended topic of this post was:

how to convert such outhouse into a proper humanure composting operation

This issue is discussed in detail in the 4th edition of the Humanure Handbook, published in May 2019. Here's an important excerpt:

"Remember that composting, by definition, requires (1) human management, (2) aerobic conditions, and (3) the generation of mesophilic and thermophilic heat by microorganisms. “Composting toilets” is a misnomer. Composting is unlikely to take place inside any toilet receptacle because sufficient biological heat will not be generated, for several reasons. For one, the mass of the collected toilet material may be too small; for another, the collected material may be too dry due to urine separation or intentional dehydration; for another, the toilet material may be anaerobic. Most devices that people call “composting toilets” would be correctly referred to as “dry toilets” or “biological toilets,” but they should not be referred to as “composting” devices. They do not make compost; instead, the result is decayed organic material, or what’s known as “septage,” which has not been subjected to the biological temperatures of true compost and is therefore not sanitary. A 2017 research study pointed out that “conditions required for pathogen or parasites die-off. . . . are seldom or never achieved in UDDTs [urine diverting dry toilets] feces chambers in real situations.” [Humanure Handbook 4th edition Chapter 12, pages 144-145]

To make compost, generally a compost bin approximately one cubic meter or larger in volume is required. To make compost from toilet material, the material is collected in a "compost toilet" and then composted in a separate compost bin where true composting conditions can be achieved. Otherwise, toilets that collect toilet material without water but don't compost the material are actually "dry toilets," certainly NOT "composting" toilets.

"In 2018, the US Composting Council (USCC) defined compost as the product manufactured through the controlled aerobic, biological decomposition of biodegradable materials. The product has undergone mesophilic and thermophilic temperatures, which significantly reduces the viability of pathogens and weed seeds and stabilizes the carbon such that it is beneficial to plant growth. The Association of American Plant Food Control Officials (AAPFCO) approved the new definition for compost because it emphasized the pathogen-removing thermophilic process, differentiating it from many products often confused with compost. This more completely defines what our products are so that people out there wanting to call their products compost cannot do that without meeting this definition, said Ron Alexander, the USCC's liaison to AAPFCO, who had labored for years on the updated definition. A lot of people call a lot of things compost, incorrectly, and it’s hurting the composting industry. We don't want to have the compost industry's product being confused with other products after all the work we've invested in best practices and quality product standards, said Alexander. The new definition helps the producers of other products, from biochar to mulch to dehydrated food, worm castings, and anaerobic digestate, to more clearly differentiate their products as not being compost. For example, “vermicompost” is a misnomer. The correct term is “vermiculture.” The end product of vermiculture is not compost; it’s worm castings. Vermiculture is not dominated by aerobic microorganisms generating biological heat. It’s dominated by red worms. Thermophilic microorganisms would kill those worms. The final product is not the same as compost, and it should not be called compost. Nor should a lot of other things that are referred to as compost." [Humanure Handbook 4th edition Chapter 8, page 70]

Cristo Balete wrote:Even the LovelableLoo video says it's not a composting toilet, it's just a "collection device" for composting elsewhere.

The threads at this site should probably make a bigger distinction among composting in

(1) composting toilet with a tank,

(2) bucket system that is composted out of doors

(3) A cesspit dug into the ground with no container, which is what this thread is talking about.

"A bucket system that is composted out of doors" would correctly be referred to as a "compost toilet system." To quote the 4th edition of the Humanure Handbook (Chapter 12, page 159), "There are two words that should never be used in association with compost toilets. One is “waste,” as I have repeatedly mentioned, and the other is “bucket.” Some compost toilets utilize five-gallon buckets as toilet receptacles. Others use drums, urns, barrels, bins, or any receptacle that is water-tight and manageable, depending on the situation. Five gallons or approximately twenty liters is a good capacity for easy handling by one person, and a five-gallon container will hold approximately one week’s excretions of one typical adult, assuming an appropriate cover material is used. Five-gallon plastic buckets are easy to come by in some countries, such as the US, where they can be acquired cheaply or for free when recycled. In other countries, believe it or not, they can be nearly impossible to find. Some people who grow up in water toilet cultures can become perturbed at the idea of using a compost toilet. One person posted on a blog during Cape Town, South Africa’s severe drought in 2018, “I’m not going to shit in a bucket. That’s disgusting!” I responded that they would be shitting in a compost toilet, as opposed to shitting in a pot of drinking water. Funny that defecating in drinkable water is not considered disgusting at all, even when the potable water supply had dwindled to dangerous levels and was looking like it might dry up completely..."