Composting Toilets: Turning people poop into safe, usable compost


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Everybody poops. But few people use their poop to help around the garden. Most of our waste is carried away by sewage pipes and ends up far, far away. The thing is, waste contains tons of nutrients that plants love. It doesn’t make much sense to flush away fertilizer, and then spend money buying bags from the garden supply store. Toilets usually use more water than any other appliance in the home, and transporting sewage consumes a lot of energy. Most of that electricity comes from polluting sources like coal and natural gas. So, flushing the toilet wastes water resources and adds to our carbon footprint.

There is a better solution. Composting toilets are available that convert waste into fertilizer. Toilet Composters are safe, sanitary, and easy to operate. Composting toilets are also known as biological toilets, waterless toilets, and dry toilets. These toilets come in many different designs, but they all do basically the same thing: they use naturally occurring bacteria to turn excrement into soil. Human waste is very high in nitrogen, so a green toilet usually requires additional carbon to ensure proper composting. Toilet paper provides some carbon, but sawdust and leaves may also needed for balanced compost (and they can help control odors too).

Composting toilets work very much like other composters. They don’t fill up as quickly as you might think, because bacteria actively break down the contents into heat, gas, and compact soil. Given time, the contents of composter toilets will shrink to a fraction of their size. In general, human waste will reduce to 2-10% of its volume when converted into compost. This means that composting toilets are well suited for gradual use over an extended period (such as in a hunting cabin, RV, or single person home), but they may not be the best plumbing option for a family reunion or large BBQ.

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