Back in the 1980s Nancy Rosalie got tired of flushing the toilet and knowing human waste was going to, well, waste.
So she decided to put it back into the nutrient cycle where she says it belongs.
“Poop is my passion,” Rosalie said. “It stems from my recognizing that all nutrients recycle and in nature those cycles happen because everything that [exists] becomes something else that can be used.”
When it comes to human excrement and urine, however, western culture typically considers it a waste that needs to be treated with chemicals, and the byproducts of that process can create environmental problems. Switching from a flushing toilet to a dry toilet can instead turn that waste into usable composting materials.
Dry toilets take several forms. At its most basic, it’s a toilet that does not use water for flushing. Instead, human waste is collected in a storage compartment and a carbon additive like sawdust, peat, wood ash or newspaper is mixed in to break down the waste through aerobic decomposition — otherwise known as composting.
The most common forms of dry toilets are outhouses, self-contained composting toilets and incinerating toilets.
Self-contained composting toilets that look like a flush toilet are often made out of strong polypropylene. Urine and excrement are collected and composted in a removable container below the toilet seat. They often have a vent to expel gas build-up with a fan. That means they do require either electricity or a battery.
Incinerating toilets collect and burn waste into ash in a compartment below the toilet. These toilets are powered by either electricity or propane.
For her part, Rosalie prefers the third option — the outhouse. Unlike composting or incinerating toilets, outhouses are located outside the house, so you have to walk outdoors to get to it. But Rosalie said that small inconvenience is more than made up for by the benefits of her composting system.
“What I have noticed about the commercial incineration and composting toilets is that they are attempting to minimize what comes out of the toilet so that emptying it becomes a minimal task for the user,” she said. “In the system I use, I am attempting to maximize what I produce so I can recycle more.”
She also likes using a dry toilet that does not require a power source to operate.
Since Maine law requires outhouses to have a collection area that can be cleaned out, it made sense to Rosalie to compost.
“There is nothing in the law that suggests what you should do with what you take out,” she said. “Other than that, it can’t leave your property.”
In the winter months, human waste is collected in a pit below the outhouse. During the summer, Rosalie uses a bucket to capture what she terms “the proceeds” of the outhouse. She empties those buckets into a compost pile along with food scraps and garden waste. Into that she mixes leaves or hay to start the composting process.
At the end of the summer she cleans out the winter waste from the outhouse pit and uses that to cap off the summer’s compost pile. That pile will compost for three seasons.
“Between the heat generated by the composting and the length of time before I use it, I am confident that any ‘nasties’ have died and I can use it to treat my garden,” Rosalie said. “I know what I have eaten, I know how I have treated it and I know it provides nutrients — this is how things are supposed to work.”
The composted materials from a commercial, self-contained composting toilet can be used in a similar fashion.
You can make your own indoor composting toilet, Rosalie said. When the world was preparing for possible disruptions to the power grid due to uncertainty of how computers would react when they rolled over to 2000 at the end of 1999 — or Y2K — Rosalie made one for her mother. She used a store-bought handicap potty chair, a bucket and a bag of sawdust next to it.
“It wasn’t pretty, but it worked,” she said. “Anyone can do this and it’s a good way to try a dry toilet and see if you like it.”
When done properly, dry toilets do not smell badly, she said.
Rosalie shares her love and knowledge of composting human waste every year at the Maine Organic Farmers and Gardeners Association Common Ground Fair where she maintains the “common thrones”. These are composting outhouses that supply materials for flower gardens on sites adjacent to the fairgrounds.
After four decades of using a dry toilet system, Rosalie said she has no plans to ever go back to a flush toilet.
“I grew up an urban gal with a flush toilet but after switching to the dry toilet I would not do anything else,” she said. “Heaven help me if I get too feeble to haul a bucket.”