Fertilizer from Urine Means Clean Rivers, Sustainable Farms
By Abraham Noe-Hays
What if a polluting waste from your body could be transformed into a resource that benefited the environment? In what could be called “extreme recycling,” 170 people in and around Brattleboro, Vermont donated 3,000 gallons of their own urine to be reused this year on a local farm as fertilizer, as part of a groundbreaking program run by the Rich Earth Institute. And although the idea can catch people off-guard at first, the project has had a very positive reception within the community.
“In the beginning we were very nervous what people would think,” said Kim Nace, administrative director of the Rich Earth Institute. “But it’s been a wonderful experience. As soon as people understand the purpose—how it helps keep the rivers clean and supports sustainable agriculture—they get right on board.” Nace’s reticence has evaporated in the last two years. She now gives public tours of her home’s urine-collecting toilet, and in November she addressed the delegates assembled at the U.N. in observance of World Toilet Day.
Urine contains high levels of nitrogen and phosphorus. Flushed down the drain, these elements cause algae blooms in lakes and estuaries, killing fish and destroying aquatic habitat. But if the urine is recycled to farmland instead of being flushed, levels of nitrogen and phosphorus in wastewater can be reduced by 75%.
On the farm, the same nitrogen and phosphorus make urine a powerful, locally-produced fertilizer. According to the Rich Earth Institute’s research director, Abe Noe-Hays, one person’s yearly output is enough to fertilize about a tenth of an acre of hay, or to grow 300 pounds of wheat—which would make a loaf of bread every day for a year. The Rich Earth Institute has been working with Fairwinds Farm, in Brattleboro, to conduct field trials. With support from a USDA SARE grant, they determined that test plots of hay treated with urine grew just as well as plots that received chemical fertilizer.
Fertilizing with urine is not a new idea. It was vital to Chinese agriculture for 4,000 years, and continues to be used by gardeners around the world—including many in the United States. Since WWII, synthetic chemicals have displaced most natural fertilizers, but rising energy costs and resource depletion are driving up chemical costs, making the idea of local, renewable, urine-based fertilizer attractive again.
On the flip side, flushing urine down the drain is becoming increasingly expensive. To protect the aquatic environment from nutrient pollution from urine, the EPA and state governments are requiring towns, cities, and individual homeowners to spend heavily on technologies that remove nitrogen and phosphorus from sewage. “By keeping those elements out of the water from the beginning,” said Noe-Hays, “we’re solving the problem with less expense, and we are producing a valuable fertilizer at the same time.”
This project is the first of its kind in the U.S., but in Sweden urine reuse is more widespread. Since urine is commonly sterile (and is even used as an emergency antiseptic), Swedish guidelines approve direct use of diluted urine as fertilizer on home gardens. Since the Rich Earth Institute collects from a wide population, it takes the precaution of sanitizing urine before reuse, either pasteurizing it or storing it at room temperature for a month so that the naturally occurring ammonia has time to destroy potential pathogens.
The Rich Earth Institute has the support of Brattleboro’s Department of Public Works, and will be working with two new farms in 2014. “It’s amazing how fast this is growing,” said Nace. “My dream is that within my lifetime urine recycling will become commonplace, and people in the future will wonder why we ever did it any other way.”
To learn more, visit www.RichEarthInstitute.org.