From bucket toilet to permaculture flush compost toilet

I just switched from a bucket system to a FLUSH COMPOSTING system! My bucket system just was too labor-intensive.

My flush system is almost as permaculture as you can get and works like a dream. After the hard work of putting in the system, there's little to no maintenance, no compost to deal with, no smell and the nutrients are feeding our grove of shade trees and will feed our pollinator garden in the spring. It is not the least complicated, it's just hard work. Even so, two of us did the whole thing in three days. It cost us about $100 because we had access to a lot of materials we could reuse but it wouldn't cost much more if you had to buy everything.

One of the nice things about it is that it is totally hidden and undetectable--just sayin', for you folks who have to do it under the radar. Of course, I situated our house just for the purpose of being able to hide the system but your results may vary as far as it being hidden.

Right now we're using a small amount of fresh water to flush it but my first project in the spring will be to switch it to grey water.

I adapted Anna Edey's system that she published in her book, Green Light at the End of the Tunnel. The great thing about this system as opposed to a septic tank setup is that septic tanks are dug so deep that the nutrients in the effluent miss the roots of plants completely and we end up with tons of nitrogen contaminating the groundwater. This system delivers nutrients right to the roots of your trees, shrubs and flowers, beautifying your land and saving our waterways. Also, she lived in Martha's Vineyard at the time she had this system and it never froze despite below-zero winter weather.

Here's how it works:

You flush the toilet and the raw sewage goes into a composting tank about 1/3 full of what Anna calls a "brown filter," consisting of aged wood chips, partially composted shredded leaves and exactly one zillion earthworms.
The solids are retained in the tank and become food for the earthworms.
The fluids drain through the drain in the bottom and enter a long french drain in a trench, covered with wood chips. Landscaping plants and flowers use the nutrients to grow lush and large. No smell, no flies, no mushy wet spots.
You'd think you would have to empty the composting tank once in a while. Not so. In fact, you have to ADD wood chips and leaves once in a while, because they break down along with the sewage and are carried away with the fluids in the form of their constituent nutrients and minerals.
In the summer, there is complete breakdown of sewage in a week. In winter it's 3 weeks.

Here are the highlights of how to build one like mine:

First, you need a slight to medium decline from your house to the leach field. If the ground doesn't have a natural decline, you can simply trench a decline into the ground to where your leach field will be.
My leach field is a meandering 40 foot long path through our grove of Sumac trees (they love nitrogen!) and through a small plot that will grow flowers in the spring.

Next, you need something to use as a composting tank. Anna Edey built a box of wood lined with plastic and rigid insulation, with a tightly fitting lid. I'm using a 55 gallon lidded poly barrel I got for free.  I intend to insulate around the outside of it with some extra straw bales I have. This will completely hide the few inches of the tank that sit above grade. the rest is all buried.

Then you need some french drain. I used flexible corrugated that came in 8 foot pieces but you can buy a roll of flexible that's all one piece or you can use rigid PVC but you lose the ability to go around obstacles and have a more organic-looking leach field.

Next you need A LOT of aged wood chips. I had a friend with a huge pile that they had forgotten they had.
And you need a fair quantity of pea gravel to create a thin layer in the bottom of your trench. Our land is hella rocky so we collected our own.
And about 3000 earthworms. You can collect them yourself and start a mini worm farm like we did or you can seed the tank with as many as you can find and the numbers will double every month as long as they are fed. You can also mail order them.

Then you need shovels and strong backs, or a friend with a trencher, or a rototiller or some other way to create a trench. Anna's prototype was barely buried and it worked perfectly for years. She finally decided to upgrade to a deeper, lined trench to satisfy skeptical people.

We live right next to a small embankment covered in sumac and other wild plants. About 10 feet from the house we dug a hole just off the edge of the embankment deep enough to put our barrel in with about 5 inches sticking up above the level ground surrounding the house. We ran a drainage pipe from the black water holding tank (we live in a travel trailer but you can do the same with your flush toilet), trenched it in and buried it, making sure there was a decline to the composting barrel.

We cut a hole in the SIDE of the barrel near the rim for the sewage incoming. DO NOT put your sewer pipe into the lid, in case you have to service the composting tank (add worms and filter materials, remove a sock Jimmy flushed).
We also cut a hole in the side of the barrel at the bottom to fit the outgoing drain pipe into. We could have cut it into the bottom but logistically it was easier to put in the side.

Then we created a 13-inch deep trench from the outgoing drain hole, down the tree-covered embankment in a meandering path, through the flower bed and back into the grove, ending at an abandoned groundhog hole.
We lined the trench with a thin layer of gravel to prevent dirt from clogging the holes in our french drain, which are pretty small.

Then we went back to the composting barrel and added some PVC fittings; one to attach our sewer drain to the "incoming" hole; a short length of PVC pipe on the inside of that fitting with a 90 degree elbow so that the sewage would enter the barrel about in the middle; another fitting at the bottom to attach our "outgoing" french drain. This one has a piece of 1/4" galvanized hardware cloth across it to prevent our filter material from flowing out into the french drain.

The lid of the barrel and the "incoming" fitting HAD TO be airtight to prevent smells so we took care of that. Then we laid our french drain into the trench and connected it to the "outgoing" hole at the bottom of the barrel. We started with an 8 foot length of non-perforated pipe to make sure that if there was going to be any smell, it would be that much farther from the house. Then we back-filled the trench with wood chips to cover the drain pipe.

Ok, now the moment of truth had arrived. Our black water tank had been completely full for 3 months, which is why I set up the bucket composting system in the first place. I had to open the black water valve and drain it into our new system and see if anything horrible happened. I held my breath lest I be assaulted with 3-month-old sewage fumes, and opened the valve. It began to drain and I took an experimental whiff. It smelled like a non-threatening fart for a moment but it quickly dissipated. My partner said she didn't smell anything. I checked for any ominous puddles. None! IT WORKED!!
At least, to that point. We needed to use it for a while before we could really say if it worked as Anna said it would.
We have done that, and so far, we're in flush-toilet heaven!

Bonus: about 3 days after the project had been completed and launched, I was managing some of the dirt piles left behind by the trenching and I turned up a bunch of worms which I wanted to add to the composting barrel. Boy, I DID NOT want to open that barrel of fully ripened poop. But after carrying buckets of sh*t for 3 months (the wife REFUSED to participate), I thought, "What the hell. This may be the last time I have to face mass quantities of raw sewage. Bite the bullet and do it!" I carefully lifted an edge of the lid and waited...no smell. I mean, like, NONE. I quickly dumped in the worms and shut the barrel. I was tempted to put my face a little closer just to see if it was really as odorless as it seemed, but I was more tempted to not stick my head in a barrel of crap.

So there you have it. My daughter is preparing a video of the process with lots of pictures and explanations but it's not ready yet. I'll update when that is all ready to go.
Thanks for reading all this. Comments, questions, kudos, condemnation welcome.

I'm a big fan of Anna's ideas. I read her book Solviva and found it very inspiring.  If I could I would change our septic system to a vermicomposting flush toilet system.  I'm glad you pursued these ideas and figured a way to do it under the radar.

Sounds good.... but on areas with regular flooding it sounds like a problem. In areas short in water/no flooding it sounds like a dream.

We are in a flood prone area. Mostly flash floods, but ground water level = ground level in spring, so I can only salivate over your system.

I love this kind of system! I visited Ana Edey's house a couple of years ago and she showed us her system. Truly no smell in the brown filter box: There was a visible turd and some toilet paper under the inlet pipe, but the rest was all black compost and wood chips, teeming with compost worms.

At the school I've worked at for decades, and now at my own house, we use only dry composting toilets (two big chambers, alternating by a year or so) so we don't need to install this kind of thing for toilets (and we have severe water limitations, and would suffer frozen pipes in winter). But at the school our "straight to daylight" kitchen greywater to a canal along trees was starting to stink as our population grew, so we are going to install one for the kitchen greywater. Well, we did install it 2 years ago, but now we're rebuilding the kitchen so we had to dismantle it, and will make a new one. Learnings from that process: wood shavings clogged up the outlet despite a large area of screen and open space before the drain pipe in the bottom end of the brownfilter tank. And clogged up greywater goes anaerobic and STINKS! So then we dug out all the nasty yucky shavings and filled it with lumber scrap chunks (there's no such thing as waste wood chips here), and that worked well for a year. Unfortunately I didn't look inside before they dismantled it so I don't know how it looked; we didn't actually put worms in because sometimes large pots of boiling water might go down the kitchen drain, and people here are VERY sentimental about killing worms and flies. But the filter should still work, compost, develop an ecosystem, and it definitely cleaned the greywater before it came out into the open and reduced the stink.

I have one comment on your system. Roots can be very aggressive about getting into holes and then growing, blocking the pipe with a living plug. We had that with poplar roots that crossed some 50 feet of dry land to enter a tiny hole in a clean water pipe. We thought maybe the pipe was getting clogged with silt, but finally we broke it open and pulled out a 10-foot long tangle of roots, shaped like a snake. With our greywater since it is going to a daylight small canal, all we have to do is make sure the pipe from the brown filter comes out of the ground 6 inches above the canal, and roots won't make that jump. With your toilet system, your outlet from the brown filter will be buried in the French drain with wood chips or gravel or something, and roots will happily travel through that medium and try to block your pipe. When I saw Ana Edey's sytem, she had the soak trench lined with gravel and landscape cloth, and the area was only grass pasture, and a little way away, pine trees (that I think don't have those aggressive roving roots like willow and poplar do).

Amit Enventres wrote:Sounds good.... but on areas with regular flooding it sounds like a problem. In areas short in water/no flooding it sounds like a dream.

We are in a flood prone area. Mostly flash floods, but ground water level = ground level in spring, so I can only salivate over your system.

You know, I've been thinking about your comment for a while and it occurs to me that a regular septic system delivers all the nitrogen from your effluent directly to the groundwater anyway. I'm not a biologist or a scientist but it seems to me that any amount of nitrogen that can be uptaken by roots is better than ALL of it going into the groundwater. If there's any high ground on your property, you could dig the barrel in at that spot and even put an outhouse over it. If you plant nitrogen-loving plants on either side of the path of the leach field, they would utilize most of the nutrients flowing though the system. Worst-case scenario, you use your regular system during flood periods and switch to the more earth-friendly system the rest of the time. Remember that the solids are retained in the tank and composted by soil life. The liquids only carry whatever bacteria or pathogens they pick up on the way by, which then get neutralized by the biofilter material.
Anna Edey, the designer of the concept, had extensive lab testing done on her system and they discovered no pathogen build-up in the leach field. So it seems her system could be useful even in flood-prone areas if used judiciously.

Ok, folks, here's the moment you've all been waiting for (I flatter myself)...
We've been using our flush composting toilet for 4 months and I'm here to give an update and post a video of the build. The video is really hokey and repetitive cuz I've never done one before, but at least you'll get to see what we did.
First for the update:
During the summer & fall, it worked like a charm!! That's it. The whole update. No problems whatsoever. And then there was winter.

When winter set in, I had to come up with yet another brilliant system to ensure our holding tanks didn't freeze. Here's what I did:
I noticed that the exhaust port of our propane-burning furnace was pumping out burning hot air. I accidentally left a plastic thing near the exhaust and it melted, so, pretty hot.

Our trailer already has the cold-weather package but it's only good down to about freezing so I needed to keep the underneath of the trailer warm to prevent the fresh, black and grey water tanks and water lines freezing.
So I bought some flexible aluminum ducting like you put on your dryer (not the plastic stuff!), long enough to reach from my exhaust port, and stretch all down the center of the underneath of the trailer, with detours looping under areas like the kitchen and bathroom, and ending under the black water tank and drain portal. The opening of the duct would exhaust out into the open air so as not to build up carbon monoxide under the trailer.

Then I wrapped pipe insulation around the duct from the exhaust port down to the ground and under the trailer a couple feet. Then I salvaged some rigid ducting and a couple elbows that were about 2 inches bigger diameter and enclosed the flexible duct (that was a bit*h, I'll have to figure out an easier way to do that) down to the end of the insulation. Then I used baling wire to attach the opening of the duct over the exhaust port and turned on the heat to make sure the airflow was unobstructed and that the insulated portion of the duct wasn't going to get too hot. It didn't; I could easily keep my hand on it at the highest temp it could produce.

Next, I went under the trailer and checked that the temp of the uninsulated duct wouldn't be so hot as to melt the goodies on the under side of the trailer--that was all good too.

Now comes the messy part. My daughter and I stacked bales of straw all around the outside of the trailer to close the gap between the trailer walls and the ground, to retain the heat from the furnace exhaust. We draped them with an old insulated pool cover I got for free, to keep them dry. We had laid down scrap 2x4's covered with tar paper ahead of time to keep them from absorbing rain and snow melt from the ground. Yes, I could have bought some fancy insulated skirting and spent hours measuring and cutting and making it beautiful--and maybe I will do that at some point but we were running out of time and money so...

Anyway, that worked beautifully for a while, then I realized that moisture from the hot air was condensing in the duct and causing ice dams. So I went underneath and poked some holes along the bottom of the duct to let condensation drain out. I wasn't that worried about CO2 escaping the duct work at that point cuz I didn't notice at first that the ice dams had formed and our CO2 sensor never sounded to warn us, so the CO2 that was escaping from the seams in the duct was not entering the living space. Besides, hot air rises, right? The hot air and fumes were traveling along the top of the duct and the holes were in the bottom.

The hole-poking completely solved the problem and we were back in business! Our tanks never froze and we were able to drain the black and grey water tanks at will. Right up until something crawled into our furnace air intake and we had to switch to space heaters until we could get it resolved. But up until then, it worked great!!

And now, the moment you've ACTUALLY been waiting for...here's the video of the flush composting toilet build:  

M Wilcox wrote: Ok, folks, here's the moment you've all been waiting for (I flatter myself)...

Actually, I Have been! I have had this thread on watch to see how it works out. THANK YOU for the updates! I'll watch the video later...
:D

Interresting to read the thread! Been looking at different options for waterless toilets and urine separating toilets for school project. Like the composting toilet solution! Would be superkind if you guys would like to fill in a survey that we are doing for school to better understand needs around this issue http://bit.ly/2UyXoxa. Thank you!!  

Hi folks. I need to do one more update on our flush composting toilet.

We actually managed to scrape together enough money to buy a tiny homestead so my flush composting system has been left behind but y'all deserve to get the full story so here goes:

I actually did run into a problem with the system. I managed to resolve it but learned some lessons for the new system I'm gonna install here on our new homestead.
What happened was that the hardware-cloth filter that was helping to retain the brownfilter material in the barrel got clogged up. Why did this happen? Well, I should have used a thick layer of straw or other easily-permeable material in the bottom before adding the brownfilter because the decayed leaf litter sifted to the bottom and created a whaddayacallit--that thing that develops to keep pond water from soaking into the ground--a seal of sorts. Then the pee and grey water backed up into the barrel and drowned all our earthworms which means no high-powered decomposition going on. Just regular wormless composting.

So then I had to--OMIGOD--empty the barrel to fix the situation. Need we mention I wasn't looking forward to that? But here's the interesting thing. Even though I had just emptied my holding tank into it the day before, when I took the lid off the barrel there was no bad odor. None. And nothing in the barrel looked like poop. It looked like muddy slurry.

But what was I going to do with 50 gallons of partially-decomposed sewage? Well I hope I don't get a lot of hate for this but here's what I did: The steep slope that made up our leach field was a grove of sumac trees and other wild plants that we weren't using for food or medicine and it was riddled with groundhog holes. I thought to myself, "Self," I thought, "What is an outhouse? It's a hole in the ground into which we put sewage. What is a groundhog? A garden-destroyer. What is my solution? Turn groundhog holes into mini-outhouses!" So I proceeded to take 10 five-gallon buckets of slurry and pour them down the outhouse holes--er, groundhog holes. Needless to say we didn't see any groundhogs for a good while.

Now, back to the barrel.
1. I scraped the leaf litter off the bottom of the barrel and
2. cleaned out the hardware cloth filter and replaced it.
3. Then I got one of those PVC filter-cage thingies (I wish I could remember what they're called) that you put on the end of a suction hose to keep stuff that is too big from coming through. It's not really a filter, more like a strainer with bigger holes. I wanted a lot of surface area and holes that were nice and big so that they wouldn't clog too easily but small enough that not too much solid material could get through. Anyway, I
4. screwed that to the PVC outlet fitting at the bottom of the barrel.
5. Then I took some rocks about the size of golf balls and stacked them around that pre-filter as a sort of "pre-pre filter."
6. Then I put in a thick layer of straw,
7. then the brownfilter material of mixed aged wood chips and partially composted leaf litter.
8. Then I dug up some more earthworms and chucked them in.

We had no more trouble with the system from then until we moved. Really, the barrel-emptying-and-cleaning, which should have been the most objectionable part of the process, ended up being merely a lot of work. And a lot of satisfaction thinking of the groundhogs waking up in the morning, having their coffee and then heading out to their garden-wrecking job only to encounter their entry hall filled with crap. MWAHAHAHA!!!

So the takeaway here is that I really will be better off in my next build to use a low, wide container rather than a tall narrow one for a few reasons: One, it will be easier to work on if needed (reaching to the bottom of that buried barrel to the drain was really hard). And I think it might drain better if everything is more spread out and there will be less pressure on the drain if everything is horizontal rather than vertical. The worms might like it better too if it's not so deep.
Two, next time I will put one of those filter-cage thingies on right from the start and create a nice, porous layer over it to prevent future clogging. I may even create an overflow pipe like they have in toilets so if it gets too full of fluid, it'll have a place to drain out into the leach field. I don't expect to have this problem anymore though because I'm in a house and will be able to flush regularly rather than releasing a whole holding tankful at a time and chance overwhelming the system like in the travel trailer. But better safe than sorry!
One last note is that our free-range chickens quickly discovered that earthworms hung out near the French drains. The chooks started digging the wood chips out of the trenches to get at the worms, revealing the French drain pipes. There was no smell at all but it was unsightly. So what I'll do next time is get scraps of wire fencing, hardware cloth, chicken wire, etc (I always seem to find tons of this stuff) and stake it down over the trenches. The weeds and plants will soon grow over and cover it up and the girls won't be able to dig out the wood chips anymore.

Overall, the system served us well for several months before needing adjustments and I'm stoked to get my new system put in at the new homestead.

M Wilcox wrote:Hi folks. I need to do one more update on our flush composting toilet.

...

Overall, the system served us well for several months before needing adjustments and I'm stoked to get my new system put in at the new homestead.

Excellent and helpful thread! How have things gone at your new homestead?

We are gearing up to build a vermifilter septic system in the spring. We are basing ours on Wendy Howard's work vermicompostingtoilets.net design & construction -- she updated the Solviva design to correct for a lot of problems similar to the ones you had with your first system, and on paper, it looks like a pretty robust design, unlikely to clog!  Of course the proof will be in our poop-pudding once we get to that point...

Eager to hear how it's going at your new place. And we will for sure be posting our progress once we get there!

Kimi Iszikala wrote:[quote=
Excellent and helpful thread! How have things gone at your new homestead?

Eager to hear how it's going at your new place. And we will for sure be posting our progress once we get there!

I would like to give an update on the flush composting system.

We ran into a problem with the barrel I was using. The exit drain got clogged with leaves because I made the mistake of using whole leaves. I didn't have a way to shred them so I put them in whole. They worked their way to the bottom and acted sort of like one of those flat rubber discs that people used to plug their bathtubs with in the old days. Because the barrel was tall and narrow, when the system backed up, the worms had no place to go and drowned (RIP, worms!) Next time, I will use an IBC tote, which will  1. be bigger and hold more, 2. spread any backup over a larger area, hopefully not drowning our worms. Also, I will shred the leaves next time (we have a shredder now). And I'll make the drain clog-resistant.

When I realized the barrel was not draining, I also realized I was going to have to empty it and clear the drain. Oh dear! So I put on my ugliest work clothes and headed for the tank with a bucket and shovel.
As Gomer Pyle would say, Surprize, surprize, surprize! The tank and sludge smelled like nothing but earth. I was flummoxed! Anyhow, I bailed out the tank and poured the buckets of sludge down groundhog holes on the ridge, thereby delivering the nutrients directly to the roots of the plants and no doubt pissing off every groundhog in the area. Then I cleared the drain and put a little cage around it that would keep anything from blocking it again. Then I took a really hot shower with lots of soap!

Moral of the story, a much larger tank than you think you need is the right size! Still, the system worked wonderfully for a long time before we encountered an issue, and I learned enough to do much better next time.
We have since moved and started over. My new flush composting system is slated for next year.

I really appreciate this thread.  We're in a house bus and have a flush toilet to a 400l black water tank.  One of my projects for this summer is this very thing - I'm tired of hauling these nutrients off of our land.  

To mitigate the risk of clogging, aside from the 2 ideas already mentioned (larger surface area and Wendy Howard's bypass pipe), you can use coarser media and an air cavity along all the sidewalls.  The sidewall air cavity is illustrated in Dean Satchell's vermifilter.com designs using an agricultural crate to hold the media off the wall here or poly pipe with shade cloth here.