Lynsey Grosfield
November 13, 2015

Systems are set up on a large scale to collect urine for using as agricultural fertilizers. 

L’Uritonnoir/Facebook

Most gardeners have popped a squat once or twice in the garden, especially when going indoors was otherwise impractical. Unbeknownst to many, however, this action enriches the soil with both macro- and micro-nutrients.

Vermont’s Rich Earth Institute recently made news with a pilot project to divert urine from the septic system to agricultural use, joining Germany, China, Sweden and many developing nations in experimenting with urine diversion and re-using human waste for practical and productive ends. This movement is broadly called “ecological sanitation.”

The Case For Urine

Urine has the same NPK ratio as synthetic fertilizers. 

SuSanA Secretariat

Urine from a typical person, though not sterile, has a relatively low load of potential human pathogens and is also far lower in heavy metals like lead and cadmium than solid human waste. The ratio of nitrogen, phosphorus and potassium (NPK) is reported to be around 10:1:4, comparable to a commercial fertilizer. A family of four can reportedly produce the equivalent of a 110-pound bag of solid chemically synthesized fertilizer yearly, but instead of being used, all of those nutrients are being flushed into the septic system.

With topsoils eroding, wastewater treatment requiring ton of energy, and phosphate rock (the source of agricultural phosphorus) being mined unsustainably, peecycling can be a logical solution.

Collect Your Pee

On a small scale, urine can be used in the garden simply by peeing in a watering can and diluting it with water. In high concentrations, the nitrogen and salts in urine can burn a plant’s roots, which is why dogs leave those yellow spots on the lawn. Dilution prevents this from happening.

For a potted plant, urine can be diluted with five parts water for every one part urine (5:1); for general use, use eight or 10 parts water for every one part urine (8-10:1). Irrigation is important when using your pee as fertilizer to prevent salt buildup.

On a larger scale, investing in systems like a urine-separating toilets can be a part of a free soil fertility and sustainable sanitation plan. L’Uritonnoir (pictured above) is a cheap and simple urinal design that plugs into a straw bale: showing up at festivals around Europe, these easy toilets create a rich compost while minimizing bathroom line.

Regardless of how it is done, peecycling is the first wave of sustainable sanitation planning. And, if the public can get over the “ick” factor with pee, it may be time to start the conversation on humanure!

About the Author: Lynsey Grosfield is the founder of BiodiverSeed, a global seed swap network devoted to the exchange of self-harvested, organic and heirloom seeds with the goal of preserving maximum genetic diversity. Follow BiodiverSeed on Twitter.

 



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