Every day, Central Americans flush millions of pounds of bodily waste down the toilet, consign it to deep privy pits, or simply leave it on the surface of the ground. One way or another, much of this waste ends up contaminating water and causing disease. Yet simple technologies exist to end the profound environmental and health hazards these practices cause, and to instead convert our least-loved waste into agricultural fertility. SHI is working to give farmers the tools to turn this waste into a resource, keeping it out of the water, and using it safely and hygienically to rebuild the soils of their farms.
As farmers and gardeners around the world are aware, manure is a wonderful fertilizer. It feeds the soil, builds organic matter, and releases nutrients to plants, bestowing fertility that can turn barren earth into rich gardens. While livestock manure is of unquestioned value, people often overlook the "human manure”, and more importantly the rich levels of phosphorous in their urine.
"Eco-sanitation" is a progressive approach to sanitation that encourages the beneficial reuse of human manure, in addition to the protecting the user from disease. The "eco-sanitation" umbrella encompasses a wide range of toilet designs, but they all share three characteristics: they are safe and hygienic to use, they are non-polluting, and they recycle human manure back into ecosystems where it can be reused. In the North, composting toilets are the best-known ecosan systems, but dehydrating toilets are widespread in the South, due to their low cost and simplicity of operation.
In March and April of 2007, SHI built its first ecological toilets in Honduras and Belize, with the help of Abraham Noé-Hays, an ecological toilet designer from Vermont. These toilets are all urine-diverting toilets, meaning that the solid and liquid portions of each person's "deposit" are kept separate by means of a funnel-shaped insert in the toilet stool. The urine is piped to a sealed plastic container and the solids fall into the chamber below. At the end of a visit, the user sprinkles a mix of dried earth and wood ash down the toilet to cover the solids, which prevents odors and flies and begins the drying process.
Remarkably, the urine contains over half of the nutrients found in human manure, and over three quarters of the nitrogen. It is also nearly sterile, and the few bacteria that are sometimes present are destroyed after brief storage. Urine is a potent chemical fertilizer, and must be diluted with water before use so as not to burn the plants. According to the field staff, it is also a natural tool for discouraging crop-destroying leaf-cutter ants. The fecal portion of human manure is more challenging, from a health perspective. It can contain numerous disease organisms, and it’s inappropriate disposal is the source of many life-threatening illnesses, especially among children.
However, it is nutrient-rich and contains considerable organic matter, making it a valuable soil builder if used correctly. Users of the Honduran toilets resolve this issue by using the dehydrated solids solely for fertilizing trees. They dig a hole beneath a tree, deposit the dried material, and then cover it with a thick layer of soil. The design built by the Belize staff uses a black solar collector to heat the solids, destroying pathogens, which allows for a wider range of uses.
The ecotoilets benefit the household and community by producing free, organic fertilizer, conserving water, preventing pollution, and encouraging good health. Families with ecosan toilets are able to increase their harvest without resorting to chemical fertilizers, and are under less pressure to clear more forestland for cultivation. These toilets are quick to build using local materials, and once the investment is made they can produce their valuable products for decades.
How can you help? Give a Build an Eco-Toilet Gift of Hope to your friends and family!
Click the thumbnails below for full-sized diagrams created by Abraham Noé-Hays.
UPDATE from Abraham Noé-Hays: "In January 2009, I visited the ongoing solar toilet project in Belize, and then went to Nicaragua to help initiate a similar project there. Since the original workshop two years ago in Belize, the SHI staff have made great strides. Most notable is the mold that they fabricated that allows them to manufacture up to three urine-diverting toilet stools a day. The production process is efficient and sustainable, requiring for materials only locally available concrete and plastic pipe. Production is fast enough that they are even able to sell stools to community members who want to improve their own toilet facilities.
During my visit I had the chance to see numerous solar toilets that SHI Belize had built, and to discuss possible improvements in the construction process and in user education. One solar toilet owner, Mr. Fred Williams, was especially pleased, and showed us a lime tree that he had been fertilizing with the urine he collected from his toilet. The tree used to be weak and yellowed, he explained, but after applying urine (mixed with water to make a gentle fertilizer), it had turned green and vigorous.
In Nicaragua, field trainers Ramón Osejo, Rafael Jarquin, and Roberto Rostran participated in the solar toilet training, constructing a solar toilet for a participating family in the Kukra Hill region. Several family members helped extensively with the construction, going the extra mile to make Nicaragua's first solar toilet both beautiful and comfortable to use. Don Ignacio told me why he was excited for his family to have this toilet--with SHI's assistance, he had already seen the benefit of using the manure from his livestock as an organic fertilizer, and now he wanted to take advantage of the value of his own family's manure."
PHOTOS: SHI participant farmer Fred Williams (top, right) shows off his new eco-toilet in Belize; Honduran family (lower, left) proudly shows their eco-toilet mid-construction.
- Learn More: Belize
- Learn More: Honduras
- Learn More: Nicaragua
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