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Install a composting toilet

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Even if you're familiar with the idea of composting your food scraps, composting your own poo is probably a little harder to envision. Rest assured, composting toilets (also known as biological toilets, dry toilets, or waterless toilets) do not resemble the camping outhouses that likely haunted your dreams as a child. Modern composting toilets are clean, odorless, conserve energy and water, and act as a waste treatment plant in your very own house. The many advantages to using one are likely to outweigh any initial squeamishness you might feel.

How to install and use a composting toilet

Composting toilets allow for the aerobic decomposition of human waste into a nutrient-rich humus, wonderful for fertilizing trees and gardens. Depending on the design (some work in conjunction with a graywater system), your contact with any unprocessed waste is reduced to the turn of a crank or push of a button, necessary to get oxygen into the system.

Typically needing to be emptied only once to twice a year, the finished fertilizing product is about 10-30 percent of the original volume. Some designs allow you to add vegetable scraps that will also be composted, which will reduce your total household waste. The cost of a store-bought composting toilet is actually quite high, with prices ranging from $1,000-$5,000. However, depending on where you live, this may be comparable to installing a septic system.

If you choose to build your own composting toilet, a book such as Joseph Jenkins' Humanure Compost Toilet System Instruction Manual will walk you through the process.

Find it! Composting toilets

There are different types of composting toilets to choose from, and depending upon how you want to use it and what your situation is, you'll choose differently. Envirolet - Composting Toilet World has a good description of the types of systems out there, and how they work.

Before you buy

Thankfully, your bathroom won't smell like an outhouse if you choose to install a composting toilet. The odor associated with regular sewage is due to anaerobic respiration involved with the decomposition of waste in a low oxygen environment (i.e. submerged in water). The byproducts of anaerobic decomposition include nutrient-rich effluent, flammable methane, and other smelly gases. In a composting toilet, oxygen is abundant so that decomposition into compost happens aerobically, and consequently without foul odors.

Installing a composting toilet helps you go green because...

  • It conserves water and energy.
  • It creates a valuable fertilizer from captured nutrients, which otherwise would be lost.
  • It manages pathological waste safely, as an on-site waste treatment plant.

The National Resources Defense Council (NRDC) has reported that in 2005 there were more than 20,000 closings and advisories at public and private beaches. The bulk of these closings were due to improperly functioning sewage treatment plants and septic systems. The US Environmental Protection Agency (EPA) estimates that 1 billion gallons of raw sewage are dumped into US waters annually. That comes to 3,000 gallons for each person in the country.[1] A composting toilet deals with the waste on-site, so it's not transported anywhere, and there is no chance of large-scale leaks and spills.

Composting toilets allow human waste (appropriately termed humanure) to compost into a rich fertilizer that can be used around trees and gardens.[2] Not only do they eliminate the problem of sewage water disposal and potential spills, but they also reduce home water consumption (Americans use an estimated 5.8 billion gallons of water to flush their toilets every day).[3] In addition to cutting water bills and conserving water, composting toilets also reduce the amount energy needed to treat municipal water and pump it to homes and businesses—an estimated 50 billion kilowatt-hours (kWh) per year.[4]


The EPA published a document detailing the pros and cons of owning and operating a composting toilet. Most of the cons focus on situations in which the system is improperly maintained. If you choose to go with a composting toilet, you must be committed to maintaining it and using it properly. Improper maintenance opens up the possibility of exposure to pathogens and other health threats. But, the models of composting toilets out there are designed to make using them as easy and as pleasant as possible and come with access to a support staff in case of questions and problems.

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