Humanure Dry Toilet Made From a Milk Crate

Modern toilets take two valuable resources, water and nitrogen rich human waste, and combine the two to create a problem: sewage. In a dry or “humanure” toilet, you cover your deposits with a layer of non-toxic sawdust. Once the toilet is full you dump the contents into your outdoor humanure pile and compost the waste at high temperatures for at least a year. You can then use that compost as fertilizer for plants. The ubiquitous five gallon bucket is the most commonly used humanure receptacle. Most humanure toilet designs I’ve seen such as the ones on Joseph Jenkin’s website make use of wood which I’m not crazy about in the wet environment of a bathroom. Even with a coat of paint wood gets grungy. Alternatively, you can buy plastic camping toilet seats that will clamp on to a five gallon bucket but they have, in my opinion, an unacceptable wobble when you sit on them. For these reasons I designed a sturdy dry toilet making use of a scavenged milk crate. Even if the idea of humanure grosses you out (and it’s definitely the most controversial subject in our book), our milk crate toilet would be great for camping, emergencies or your remote cabin.

Putting this toilet together takes just a few minutes. First, find a milk or beer crate and a five gallon bucket. Make sure that the crate you use is large enough to accommodate the bucket. And note, I know of someone arrested for scavenging beer crates behind a strip club, of all places, so be discreet or ask for permission. Incidentally, when the police finished booking the beer crate scavenger the officer placed the paperwork in . . . a scavenged beer crate doubling as an in box!

Attaching the Toilet Seat to the Crate

Next, find a toilet seat. Forage one or pick up a cheap seat at your local hardware store. In an emergency situation, you could also use the one on your regular toilet and simply bolt it back on when the zombie threat has passed and the sewage pipes are flowing again. To attach the seat to the milk crate simply position the plastic bolts and nuts that come with the lid in the center and on the short end of the bottom of the crate. Don’t over tighten.

Cutting Out a Hole in the Crate

Place the bucket so that it will be appropriately positioned under the seat. Mark the outline of the bucket on the crate with a knife and cut out a circle with a jigsaw or keyhole saw so that the bucket will fit through the former bottom of the crate.

Attaching Legs to the Crate with Cable Ties

Cut four pieces of scrap wood (we found some old table legs for a more finished look), and attach them to each corner of the crate so that the bucket projects about a 1/2-inch above the level of the crate. The legs will be approximately 13 1/2-inches. Make sure that the toilet seat will fit snugly against the top of the bucket. We attached the legs with cable ties, but you could also use screws or bolts.

Moving the Spacer

The last step is to move the spacer on the bottom of the lid, so that it does not hit the top of the bucket. Pop it out with a knife or chisel, drill another hole, and reposition.

Your humanure toilet is now done and ready for use. Simply lift the crate off the bucket when it comes time to empty the contents. Follow the detailed instructions on Joseph Jenkin’s website to learn how to properly compost human waste.

This toilet is simple to make, easy to clean, and is made of readily available materials. I think this particular design will be useful in emergencies and, when combined with Jenkin’s excellent humanure methods, would prevent the dangerous raw sewage nightmares of the sort we saw in the aftermath of hurricane Katrina. There is a creative commons licence on all the text and photos on this website so feel free to translate and disseminate this post widely. We’re “open source” here at Homegrown Evolution. If you make an improvement in the design please let us know.

The Great Greywater Debate- PVC or Polyethylene?

PVC v. Polyethylene

Homegrown Neighbor here. I’ve been wanting a greywater system for a long time. My old house does not exactly make access to the pipes easy, so I’m starting with just the washing machine. The neighbor, Mr. Homegrown, is anxious to try out a new design from Oasis.

So we have been trying to get all the pieces and get it done- and here is where we get stuck. The system can either use polyethylene tubing or pvc. PVC is ubiquitous, cheap and toxic. Just how toxic, I don’t know exactly, but I’ve never chewed on any pieces just to be on the safe side. PVC is toxic to manufacture as well. This makes polyethylene the more ecological approach. But it is very hard to find in the size we need for the greywater system. And you have to buy a minimum amount- about 250 feet is the smallest we have found so far. For my yard, we probably only need about 40 feet. Plus, you have to mail order it. If we go the pvc route, it would cost far less and we could buy all the pieces at the local hardware store. We also want the system to be replicable so that we can share it with others and encourage them to use greywater. Searching for the parts for the polyethylene version is confusing – pvc is easy and accessible. This is the challenge. So what do people think- should we go with pvc or polyethylene?

Mr. Homegrown here. So I just found a local source for 1-inch polyethylene: Aqua-Flo. Cost is in the neighborhood of 33ยข a foot depending on how much you get. It comes in 20 foot and 100 foot lengths. So I think we’re gonna go with polyethylene. Incidentally, when I called Aqua-Flo they asked if I was going to make hula hoops.

A correction and update 7/25/09: The Aqua-Flo branch I went to does not have black 1-inch HDPE tubing in stock. Other branches have it, but only in 500 foot rolls that cost over $300. A roll that long would make sense for a contractor, but for DIY greywater installations it ain’t practical. Aqua-Flo does carry a new HDPE product called Blu-lock. You can get 1-inch Blu-lock in-100 foot rolls for a reasonable price (more info to follow in another post). Blu-lock uses special proprietary fittings that are easier to assemble than conventional mainline drip tubing and, intriguingly, allow for disassembly. I’m going to test Blu-lock and will report back on the results.

Behold the Glassy Winged Sharpshooter (Homalodisca coagulata)

I finally spotted my first glassy winged sharpshooter (Homalodisca coagulata or GWS for short) sinking its vampire like feeding tube into one of my hops vines. The GWS transmits Pierce’s disease, fatal to many grape varieties including my flame seedless, a gardening frustration I blogged about last week. For your enjoyment I captured a 1/2-inch GWS specimen and scanned it. Note that the GWS was harmed in the process, for which I’m unapologetic.

While there are many varieties of native sharpshooters in California, the GWS is an interloper from the Southeast US and is much more mobile. The native varieties tend to hang out in riparian areas while the GWS enjoys jumping around backyards, citrus groves and vineyards, spreading a host of nasty plant diseases including almond leaf scorch and Citrus Variegated Chlorosis. The GWS is also responsible for spreading oleander leaf scorch. Astonishingly, 20% of home gardens in California contain oleander and 2,000 miles of highways in the state are landscaped with it. The University of California estimates that oleander leaf scorch could cause over $52 million in damage.

Dig the GWS’s built-in hypodermic syringe!

The discovery of a GWS in our yard has solved a mystery that has puzzled us for years. When sitting under the grape vine covering our arbor we’ve often felt little droplets of water, highly unusual in a place where it never rains past April. Turns out it was sharpshooter pee. Sharpshooters feed on the xylem, the water bearing veins of plants. As the xylem contains mostly water, the sharpshooter must process large quantities of material in order to survive. Excess water is puffed out their rear ends, a fascinating thing to see close up. The constant water puffing combined with their fast side to side movements make GWS seem more like machines than insects. Perhaps we could “monetize” this blog by teaming up with Hasbro and Michael Bay to create a line of glassy winged sharpshooter toys, video games and action movies.

Barring a GWS blockbuster we can instead offer our fellow plant and insect geeks an industrial film from the University of California that delves into the GWS in pornographic detail. Nice retro voiceover talent on that video UCTV (one of Mr. Homegrown’s former employers, fyi)!

If you like that video, you’ll also enjoy UCTV’s 90 minute Home Vineyard lecture. I’ll add one point to that talk: if you’ve got GWS, grow muscadine or native grape varieties. Don’t bother with table or wine grapes until the bright folks at UC figure out how to breed Pierce disease resistant vines.

Off the charts

Homegrown Neighbor here. My chicken, Chickenzilla, is at it again, producing several mammoth double-yolked eggs in the past few weeks. The brown egg on the right is more of a normal sized egg, weighing in at extra large on this antique egg scale. Chickenzilla’s egg is way beyond the measure of this scale, weighing in I’d guess at somewhere around extra, extra, extra large. Pretty good for an industrial meat chicken that isn’t supposed to be a good layer, much less survive past three months of age.

The antique egg scale, by the way, hails from Orange County, California. Orange County is now known more for Disneyland and exurban, sprawling tract home developments, but it was once a great agricultural county. This scale is a relic of its golden age of orange groves and ranches. I wonder if anyone in the OC has chickens anymore?