Everything you could possibly want to know about recycling human waste is found in the third edition of the Humanure Handbook, previously reviewed here.
In addition this heroic book tells you how to make your own small homemade composting toilet using 5-gallon buckets and a regular toilet seat, and how to compost the deposits usefully. This can be used for an emergency toilet, for a cabin, or in a motor home, or for everyday use if you have a garden. One of the videos on the book’s website details the clever idea of how a music festival used sawdust toilets instead of porta-potties to much relief.
The book is also available as free PDFs; the chapter on building your own sawdust toilet is Chapter 8.
After using composting toilets on a few sailboats and one in a relative’s cabin, I would say they are all prone to smells, breakage and disappointment. EXCEPT for the DIY five-gallon sawdust bucket described in the Humanure Handbook. Nothing to go wrong. I’ve never had a smell issue either in the toilet or the compost pile. It requires a little bit of ongoing effort, but in my opinion this is ‘positive’ maintenance as opposed to negative maintenance when any other toilet breaks down. As an added bonus the bucket can be built into an attractive box to match the style and material of your space and looks far better than almost any toilet on the market including water closets.
— Mackey McLelland
I have used this sawdust composting toilet for 10 years now without problems. There really is nothing to have a problem with. I originally envied a neighbor who had shelled out for one of the big production composting toilets. It broke in less than two years (an important mechanical part of the ‘tumbler’ was poorly designed and failed). He was left with a couple hundred pounds of incompletely composted humanure in his house. To say that he was unhappy is an understatement. He has used a sawdust toilet since then. In short, unless local regulations require a production toilet (increasingly they do not) a sawdust toilet is the way to go.
A couple of suggestions: use wood pellets if you find sawdust hard to come across; they quickly turn to sawdust. Don’t turn your humanure compost piles just leave them…for years. They will take care of themselves. You can find instructions for a sawdust toilet on line easily. It is embarrassingly simple and much more hygienic (even though most people’s first reaction, including mine, is, “Ewwww.”).
The sawdust toilet also provides a perfect emergency toilet (for hurricanes, power outages, etc) Just keep a 5 gallon bucket, 2 lids, and a bag of wood pellets in a closet. Cut a salad plate sized hole in one of the lids for use as a ‘seat’ and put the other over it to ‘close the lid’. Just make sure to dispose of the humanure responsibly after the emergency.
— Rob Groesbeck