| 06 October 2010
Practical Guidance on the Use of Urine in Crop Production: A Review
The Stockholm Environment Institute (SEI), a non-profit research institute based in Sweden, launched it's latest publication September, 2010: Practical Guidance on the Use of Urine in Crop Production, SEI EcoSanRes Series, 2010-11, Authors: Richert, A., Gensch, R., Jönsson, H., Stenström, T-A., Dagerskog, L., produced by the Ecological Sanitation Research Programme (EcoSanRes) of SEI.
The authors, researchers from Europe, Africa and Philippines, have presented the guide in three parts:
Part 1 introduces generic information and recommendations for the use of urine in crop production, dealing with the biological, physical, and some of the social issues, with examples of various vegetable, grain or fruit crops grown in Europe, Africa, India, or Central America, strategies regarding application, treatment and sanitation, handling systems, gender aspects, institutional aspects, how to conduct crop experiments, and web-based calculation tools.Part 2, details how to develop site specific and culturally appropriate local guidelines, based on the Productive Sanitation Approach, including Risk Management using World Health Organizaton's Multi-barrier approach. Part 3 gives an example of a local guideline from Niger.
Beyond the casual urination on the compost pile, or use of diluted urine in the root zone of garden trees, this publication looks at the systematic and widespread adoption of urine as a major nutrient input to local food systems. Although it addresses safety issues due to pathogens and drug contamination in human waste, the latter issue may be of more concern in the US, with the common use of large quantities of a wide range of pharmaceuticals.
It describes in detail an example from Burkina Faso of an extensive system of community scale urine (and feces) collection, storage (to reduce pathogens- one month for urine, two months for feces), and redistribution to agricultural use. In this program, 1000 urine separating toilets were distributed, 100 artisans were trained to build them, 1000 gardeners were trained to use the renamed end products, with collection by donkey cart every 2 weeks, employing over two dozen people, though the economics have not proven sustainable at this point. Perhaps the various community benefits of such a nutrient cycling program which are outlined are worth subsidizing.
Even on a smaller neighborhood or family scale, there is much useful information and inspiration to gain from this publication. The EcoSanRes Programme has published many research papers as a series.
Related to the most recent publication, is the 2004 Guidelines for the safe use of urine and faeces in ecological sanitation systems.
They also have a great poster (available in spanish too), Closing the Loop on Sanitation: ecological sanitation on a rural/single-story dwelling scale.
Urine in Recent Popular Culture
Over the past few years, there has been several popular magazine, newspaper articles highlighting the efficacy of using urine as a fertilizer, all based on the ground breaking research results being published by the Finland based University of Kuopio, Environmental Microbiology Research Group, Department of Env. Science, authored by Helvi Heinonen-Tanski and Surendra Pradhan (originally from Nepal).
Some of the popular coverage:
The Washington Post, Human Urine Safe, Productive Fertilizer, By Carolyn Colwel, HealthDay Reporter, Monday, October 8, 2007
Scientific American,"P" is for plants: Human urine plus ash equals tomato fertilizer, study says, By John Matson Sep 4, 2009,
National Geographic, Human Pee With Ash Is a Natural Fertilizer, Study Says, by Charles Choi, for National Geographic News, September 18, 2009,
and the latest from Scientific American, on growing beets with urine: Gee Whiz: Human Urine Is Shown to Be an Effective Agricultural Fertilizer, By Mara Grunbaum July 23, 2010,
And now most of us know that since May 2009, even NASA's astronauts are drinking their own (purified) urine, cost: only $250 million. I guess 92% water recovery is cheaper than hauling 'fresh' earth water, while they 'throw away' the nutrients, see here:
Innocent daytime TV audiences may have been accidentally introduced to the idea of 'pee buckets' for garden use, when it was mentioned by young actress (and permaculture certificate design course graduate) Ellen Page on the Ellen Degeneres show last year, see this great clip:
Other Urine Recycling Resources:
My first discovery that urine actually contains more nutrients to reuse than humanure does (depending on diet, nearly 10 times more nitrogen, up to twice as much phosphorus, and about five times more potassium), was when I first read John Beeby's Future Fertillty, Transforming Human Waste Into Human Wealth (1995), published by Ecology Action (the Bio-Intensive/John Jeavons folks).
The relative ease of handling urine for reuse is clear, as seen in Joseph Jenkins' clever and well researched humanure bible, The Humanure Handbook - A Guide to Composting Human Manure, 3rd edition, which deals with the many issues relating to the more biologically active solid waste.
My favorite literary introduction to the long time use of urine in the garden (ethno-urinology?), is the humorous and informative Liquid Gold: The Lore and Logic of Using Urine to Grow Plants, by Carol Steinfeld, wonderfully illustrated by Malcolm Wells. In addition to the book, this website also offers her 'Urine Charge' stickers and coffee mugs, see:
Steinfeld has also authored the related books: Reusing the Resource:Adventures in Ecological Wastewater Recycling, and The Composting Toilet System Book.
In a face off between 'Nitrogen-fixers vs liquid gold', at Farmer Scrub's blog, where Norris Thomlinson's 'preparations for a more sustainable post-carbon life' are detailed, the basic assumption that nitrogen fixing plants are essential in all forest gardens is challenged. Using criteria from the Agorforestry News, Vol 3 Number 3, where Martin Crawford categorizes overstory canopy plants (trees and shrubs) by their nitrogen demand, Norris crunches the numbers, and concludes: ' In general, it seems urban lots don't need nitrogen-fixers for the nitrogen if the house inhabitants recycle most of their urine. Interesting!'
In a subsequent blog update, 'Liquid gold calculations revisited', Norris calculates 'one adult can provide the nitrogen for around 4000-5000 square feet of forest garden'. Such an area of food forest, if well designed, could provide a complete diet for that person.
There is a growing global alliance of human waste recyclers, The Sustainable Sanitation Alliance (SuSanA), a network of organizations (currently 125 from 45 countries) sharing a common vision of sustainable sanitation.
It is a wonderful and hopeful revelation that the amount of fertility one excretes is approximately equal to all fertility needed to grow a complete diet.
While protecting our health and nutrient cycles, let us gracefully 'Grow with the Flow'. . . .