Peecycling - The Power of Urine

David Trammel's picture

Most of us here know the power of our urine as a fertilizer. Wish the general public did.

Is "Peecycling" the Next Wave in Sustainable Living?

"According to the World Health Organization, human urine makes up less than one percent of the domestic wastewater treated at a facility such as Blue Plains, but contains 80 percent of the nitrogen and 55 percent of the phosphorous. When these nutrients get into our rivers and streams, they can cause algal blooms, for the very same reason that they're so great for farmers' fields: because they enable growth.

With enough nitrogen and phosphorous, algae can grow until they have consumed all of the available oxygen in the area, making it a "dead zone" in which nothing else can survive. This problem led to a provision in the 1972 Clean Water Act that requires wastewater treatment facilities to largely remove these nutrients before the water is released back into our rivers, a process that is both costly and energy intensive.

"If you can keep the urine out of the wastewater, you don't have to waste the resources in removing the urine downstream," Abraham Noe-Hays, Rich Earth's other founder, explains.

Although urine is perfectly sanitary after pasteurization, and effective for agricultural use, many still feel a significant "ick" factor when it comes to using urine to grow food.

"We're all afraid of our own waste," Chris Peot, manager of resource recovery at DC Water, explains. But he thinks that response can be worked around—the necessary paradigm shift is already underway. "This is sort of our new mantra: There's no such thing as waste, only waste of resources," Peot says."

Justin Patrick Moore's picture

I'm reminded here of JMG's concept of biophobia, which has been on my mind in relation to other things lately, namely some folks reactions to insects, especially fears around mosquitoes and how that causes them to treat their lawns etc, so they don't have to encounter insects outside. Rather than thinking of other solutions to the mosquito predicament, the System's answer is: douse your whole fracking lawn with chemicals. That will make things better! (ugh.)

I've peed on the compost heap here and there but haven't saved or stored it. Carol Deppe talks about the practice in her book the Resilient Garden, mentioned in other thread a few months back.

Alacrates's picture

I took up a little research project on composting toilets, the use of humanure, and the impact of sewer systems generally. (I thought if I was working as a plumber, I should probably know a bit about this!) I also was interested by the system in JMG's Retropia, where human waste was worked into biogas/electricity production.

That waste of nutrients is obviously crazy, and worse when we consider what it does to the waters that receive the sewage, not to mention all the infrastructure, and the all the chemicals needed to treat the water both on the way into the system and again on the way out.

The two detailed books I read on the subject (The Humanure Handbook and The Scoop on Poop) both recommended composting urine and feces in the same container/pile, but I know a lot of people like to keep urine separate to reduce odours. Joe Jenkins says the urine is pretty much ideal to keep humanure compost at good moisture levels, but of course you could always do that with water (and I guess rainwater & well water would be preferable to chlorinated water, though if it sits in the open air for a day, apparently the chlorine evaporates out.)

When I was in plumbing school, they showed us a really good documentary, "Crapshoot", on the subject, and it showed how we used to take care of our sewage sludge where I live (Winnipeg, MB.) The sludge is the precipitated solids they take out of waste water, they used to truck it out of our treatment plants and spray it raw on certain farming fields. Troublesome. Our province disallowed this recently, so the city was just putting the sludge in the landfill.

Better, they started a pilot program to compost 20% of the sludge, which I think is a good step, in terms of reducing methane emissions and recycling nutrients back to the soil. In composted form, there is a lot less nutrient run-off apparently. There is still the problem of all the harsh chemicals that find their way into the drains. Not sure how they deal with that, but I do know that compost microbes have amazing abilities to break down chemicals that wind up in compost, so it could be at least minimizing the harm.

My idea is that the city includes a biochar plant near the composting facilities, so the all the trees & branches the city takes down, and any nearby agricultural wastes, could be turned to biochar, creating process heat while sequestering carbon in the composted humanure. Apparently biochar is a compost accelerant as well, increasing the tiny spaces for oxygen to find its way into the pile, also moderating moisture levels and decreasing odours.

@Justin re:biophobia I definitely agree with that. Though we are averse to our wastes (for good reasons probably!) it's clear to me that we don't have to be nearly as much as we are in our current culture. Another great book I found on the subject was Gene Logsdon's "Holy Shit! Managing Manure to Save Mankind" (Actually looks like Logsdon is a pretty prolific author on green wizardry type topics.) It was a great little book, more just a reflection on manure, culture and history, rather than a how-to guide.

He gives a great overview of the use of humanure in Asia, a short version of "Farmers of Forty Centuries" sort of information. I remember him talking about how it was considered impolite not to leave a deposit in a farmer's pot before you left a shared meal! Also how containers of aging shit were kept under lock & key, seen as valuable & precious.

As far as I know, they didn't really use thermogenic composting to treat wastes, which I think is an important advance in terms of reducing the spread of pathogens, and increasing the value of fertilizer. As JMG often says, organic gardening may prove to be one of the great discoveries of the 20th C.

A few other random thoughts:

- just reading a history of Rome right now, the laundry businesses collected urine throughout the city to use in their processes (what purpose it served, I don't know, but it added to the disdain elite Romans had for laundries. I think Cicero's parents may have owned some laundries.)

- Albert Bates has said he keeps a container of biochar as a chamber pot

- reading about the fascinating speculations about indigenous people who once lived in the Amazon river basin before the arrival of Europeans - one author speculates that they used clay pots for toilets, separate ones for urine & feces. People may have had their own containers to shit in, to reduce pathogen spreading. They would sprinkle charcoal over their deposits to reduce odours & keep bugs off, as well as a lid. These clay toilets would be stacked up over time, and covered over with soil, to form raised garden mounds. The clay would eventually crack, and the contents would be very fertile, nutrient rich, char packed soil, raised up to keep above the waters when the river overflowed its bounds

Justin Patrick Moore's picture

Hi Daniel,

I was reading this and thought, with all your knowledge and skill, is there a job for you or a plumber to be involved with the initiatives you wrote about in your area? My father works for the water works as a welder (due to retire at the end of the year)... It's fascinating really. You have a lot of great ideas and practical skill from my observation, and maybe something in that sector of work might be a good way to make a living and get some of your ideas into place. Anyway, I was just thinking... Don't they need plumbers in municipal work. --Just some thinking. Not that you should take unsolicited career advice from me -far from it- I can just see you involved in something like that.

As an aside... here in Cincinnati they are currently "resurfacing" a creek in one of the valleys. Basically putting the creek back where it was before they put into a pipe and built a road over it. Ever year when we get storms the sewer system can't handle it and the storm drains back into the sewer and when that happens untreated sewer goes into river. It's a nice project because now the rain will go into the creek instead (duh:). It's an expensive project but should save the city money in the long term and there will be a nice park now down the corridor of the road this project is on. ( )

Alacrates's picture

As far as I know, I don't think there is a sewer board here in Canada, I don't think there are any elected officials engaged in any of this, I think it's just engineers who work in the provincial bureaucracy, but I could be wrong.

It kind of reminds me of that Simpsons' episode where Homer gets voted onto some sort of garbage collection public position, I remember thinking, I don't think we have that in Canada (along with the all the other direct voting on various propositions that I see from the states.)

I met up with someone who worked in the water department recently (he was a Somalian refugee that I knew from volunteering in a university refugee sponsorship program, who quickly finished an engineering degree once he arrived here!) - it definitely seems like a lot of these sort of positions are taken up by engineers. There are, I think, jobs for plumbers in the municipal workforce, just not sure if my experience so far would qualify me for these jobs.

One idea I had was to try to get training as a power engineer as well as a plumber. Most of the maintenance jobs here require basic power engineering. With a full apprenticeship in plumbing as well, I've heard that these two specialties could provide employment into old age, but I don't know yet. I'm trying to find something that I could use to transition out of plumbing gradually, once my body won't take the strain & crawlspaces, etc.!

Interesting about the creeks where you live. I remember listening to interviews with Josephine Littlejohn where she talks about aiming to divert natural water pathways, that it results in pent up energy, that wants to flow along the natural pathways!

Talking to that water engineer, Winnipeg has the same problem and is trying to separate the storm drainage from the sanitary sewers, so that eventually they are completely separate, with rain water & melt water being diverted straight into the rivers, and sewage going straight to the treatment plants, with no intermixing of the two!

Is that how they made terra preta, then? I thought we did not yet know how it was made. From wiki:
Terra preta literally "black soil" in Portuguese is a type of very dark, fertile(anthropogenic) soil found in the Amazon Basin. It is also known as "Amazonian dark earth" or "Indian black earth". In Portuguese its full name is terra preta do índio or terra preta de índio ("black soil of the Indian", "Indians' black earth"). Terra mulata ("mulatto earth") is lighter or brownish in color.Terra preta owes its characteristic black color to its weathered charcoal content,and was made by adding a mixture of charcoal, bone, and manure to the otherwise relatively infertile Amazonian soil. A product of indigenous soil management and slash-and-char agriculture,the charcoal is very stable and remains in the soil for thousands of years, binding and retaining minerals and nutrients.

Terra preta is characterized by the presence of low-temperature charcoal residues in high concentrations;] of high quantities of potsherds; of organic matter such as plant residues, animal feces, fish and animal bones and other material; and of nutrients such as nitrogen (N), phosphorus (P), calcium (Ca), zinc (Zn), manganese (Mn). Fertile soils such as terra preta show high levels of microorganic activities and other specific characteristics within particular ecosystems.

Terra preta zones are generally surrounded by terra comum or "common soil"; these are infertile soils, mainly acrisols, but also ferralsols and arenosols. While deforested arable soils in the Amazon are productive for just a short period of time, and farmers are constantly moving to new areas and clearing more land, the terra preta soil is less prone to nutrient leaching caused by heavy rains and floods because of its high concentration of charcoal, microbial life and organic matter; accumulating nutrients, minerals, and microorganisms.

Terra preta soils are of pre-Columbian nature and were created by humans between 450 BCE and 950 CE. The soil's depth can reach 2 meters (6.6 ft). Thousands of years after its creation, it has been reported to regenerate itself at the rate of 1 centimeter (0.39 in) per yearby the local farmers and caboclos in Brazil's Amazonian basin, who seek it for use and for sale as valuable potting soil.

Alacrates's picture

From what I understand, no one knows exactly how the civilizations who lived in the Amazon basin created terra preta soils, but, like the information that you've posted here, they can analyze soils for some information, and then make educated guesses from archaeological evidence. I don't think there are were any written records left behind by these civilizations, most of them were decimated by disease soon after the arrival of Spanish explorers.

For the most part it sounds like they used mixtures of food wastes (vegetables and things like fish bones), "humanure" and animal manure, charcoal, clay pots & potsherds. They may have had some special ingredients: some have speculated that they find certain kinds of fungus growing in the forest and scrape it into their mixes to help with it's transformation.

The best book that I've read on this is Terra Preta by Ute Scheub, et al.: The first half of the book focuses on how the terra preta of the Amazon might have been made, the second is about their own modern approximation of the practice, using bokashi composting, "effective microorganisms" (EM), and so on...

A few of the interesting thoughts & speculations I took from that book:

It would make sense for the civilizations of the Amazon to make a fair amount of charcoal, as wood saved for fuel tended to rot quickly in the humid rainforest, so charcoal was a way to preserve cooking fuel.

These seem to have been very densely populated civilizations, so they speculated that they used clay pots as toilets, and sprinkling crushed charcoal over deposits helps reduce odor, prevent spread of disease, and in a pot with a lid, it can begin a lactic-acid fermentation process, that both helps eliminate pathogens but also makes good fertilizer (sort of the anaerobic alternative to composting)

The book speculates that they may have stacked up these pots of wastes and charcoal, and then covered them over with soil, and over time built up long raised hills, filled with fermented fertilizer. When soil organisms and plant roots broke open the clay pots in time, this may account for the potsherds found among the terra preta. When the Amazon river rose, these garden hills would be above the water & irrigated, and they could gather fish fairly far inland.

I'm just an amateur enthusiast on all this, but I wrote up some of what I've learned on biochar and terra preta here:

Aged urine turns into ammonia which is used for 1) fulling new cloth; 2) curing and softening leather; 3) removing certain kinds of stains, greasy ones, IIRC. Was it Cicero's father to him, or Cicero to his son who said something about the smell of laundries being the smell of money?

SLClaire's picture

I'm experimenting with using urine to provide the nitrogen to one of my three garden beds of corn this year. Here's my blog post on it:

ClareBroommaker's picture

Okay, I used urine in the little orchard I had, but do not talk about it widely as it was on public property in a city that harassed a woman for having a composting toilet when I moved here 40 years ago. Since then, I have heard of no one in the city with a composting toilet. Anyway, my trees were growing very lean on nitrogen and I was also mulching to improve the soil at the same time. But they did produce and everyone seemed very surprised at how early they produced fruit from seed grown trees.

Fresh urine was diluted in found kitty litter jugs and poured through the mulch. If I had lived where the trees grew, I would have been able to do this more often and the trees would have greened up more to photosynthesize more.

So that's my story to encourage the doubtful.

Picture posted previously--

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lathechuck's picture

Just thought I'd provide a little context for the article. Blue Plains lies between the Congress and the Potomac River, in function if not exactly in geography. (Congressional sewage is pumped underground a few miles, and under the Anacostia River (a tidal tributary of the Potomac) on its way to Blue Plains). "Brown Lagoons" might be a more descriptive name for the facility.

mountainmoma's picture

In a low tech past and future, these are in all households....

".... Surprisingly enough, the average human excretes between 800 and 2,000 ml of urine per day, which contains about 9.3–23.3 g/L nitrogen, 0.8–2.6 g/L phosphorus, and 0.5–1.1 g/L potassium, as well as inorganic salts and other constituents (according to a NASA study).

How much would this fertilize? Really roughly, a tomato plant, for example, needs about 100–120 g N, 50–60 g P, and 150–170 g K (calculated from data here). If being grown hydroponically, a tomato plant would need the nitrogen from 10-15 L of urine. But if it is in the ground, some of that is already provided by the soil. That amount of urine, however, would only provide at best 10-15 g K, although the plant needs more than ten times that amount. That’s where the ash comes in. Ash has about 137 g/kg K, meaning a single kilogram would have enough potassium (and other salts) needed for a tomato plant...."

lathechuck's picture

If I've done the math right, a tomato plant needs about 10 days of average human urine over its productive life. (10-15L needed, 0.8-2 L/day produced). So, for a notional 180-day growing season, one person can fertilize 18 tomato plants?

When I was young, I noticed that the surface of a lagoon at our local sewage treatment plant was a beautiful dark green color. I was told that they were tomato plants, having sprouted from seeds flushed through the sewers. I guess it's hard to over-fertilize them (with natural sources).