Sanitation innovations help provide safe water and food.
An estimated 2.6 billion people in the developing world--nearly a third of the global population--still lack access to basic sanitation services. Contaminated drinking water can spread disease rapidly, particularly in densely populated urban areas. Meanwhile, urban food security is often weakened by the lack of clean, nutrient-rich soil and growing space for local families.
But a variety of waste management innovations offers an inexpensive solution to both problems. One promising option is the Peepoo, a disposable bag that can be used once as a toilet and then buried in the ground. Urea crystals in the bag kill off disease-producing pathogens and break down the waste into fertilizer, simultaneously eliminating the sanitation risk and providing a benefit for urban gardens. After successful test runs in Kenya and India, the bags are being mass produced this summer and sold for the equivalent of 2-3 U.S. cents each, making them more accessible to people who can benefit from them the most.
Meanwhile, in post-earthquake Haiti, where many poorer residents have been forced to live in garbage heaps and to relieve themselves wherever they can find privacy, SOIL/SOL, a nonprofit working to improve soil and convert waste into a resource, is partnering with Oxfam GB to build indoor "dry toilets" for private and public use. The project will establish a composting site to convert dry waste into fertilizer and nutrient-rich soil that can then be used to grow vegetables in rooftop gardens and back yards.
In Malawi, west Africa, a permaculture project run by Stacia and Kristof Nordin uses a composting toilet to fertilize crops. Although the units can be expensive to purchase and install, one company, Rigel Technology, manufactures a toilet that costs just US$30 and separates solid from fluid waste, converting it into fertilizer. The Indian nonprofit Sulabh International also promotes community units that convert methane from waste into biogas for cooking.
On a larger scale, wetlands outside of Calcutta, India, process some 600 million liters of raw urban sewage every day in 300 fish-producing ponds. The wetlands serve as an environmentally sound waste treatment center, with hyacinths, algal blooms, and fish disposing of the waste. The ponds provide a home for migrating birds and also produce some 13,000 tons of fish annually for Calcutta's 12 million inhabitants.
Aside from cost and installation, the main obstacles to using human waste to fertilize crops are cultural and behavioral. UNICEF notes that a government-run program in India provided 33 families in the village of Bahtarai with latrines near their houses. But the majority of villagers still preferred to use the fields as toilets, as they were accustomed to doing. "It is not enough just to construct the toilets," said Gaurav Dwivedi, a Bilaspur District magistrate. "We have to change the thinking of people so that they are amenable to using the toilets."
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|Title Annotation:||EYE ON EARTH|
|Date:||Jul 1, 2010|
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