Global Sanitation: Latrines Trounce Toilets
While Americans may consider flush-and-forget-it indoor plumbing to be the pinnacle of sanitary science, the lowly latrine could be a far better solution for many parts of the developing world, say researchers at Michigan Tech.
Associate Professor David Watkins, Professor James Mihelcic and PhD student Lauren Fry of the University's Sustainable Futures Institute analyzed worldwide barriers to sanitation. Diseases such as dysentery attack millions of people every year, often fatally, largely as a result of poor sanitation. In particular, the researchers found that a scarcity of clean drinking water is not as big an issue as one might expect.
In fact, installing water-guzzling appliances such as toilets can actually promote unsanitary conditions when the effluent is discharged untreated into once-clean rivers and streams. A properly built latrine, on the other hand, keeps sewage safely separate from drinking water.
"Our challenge has been to look at what interventions make the most difference," Watkins said. Their findings show that small changes can be more important in preserving health than big engineering projects, a fact that Watkins, an engineer, relates with some consternation. “As engineers, we like to build stuff. But handwashing is really important, too,” he said. "Even a simple thing like not dipping your hand into the water pot can make a big difference."
Getting people to change their habits can be harder than building infrastructure, however.
"They may not understand the science, and because it is about parasites and bacteria that they can’t see, they may not recognize the risks," Watkins said. The resulting lack of political pressure means that money that could go toward improving sanitation and hygiene is spent on other projects.
The Michigan Tech team, all of the Department of Civil and Environmental Engineering, undertook the study to determine why some regions, especially sub-Saharan Africa, are not making progress toward one target of the United Nations' seventh Millennium Development Goal, to halve the proportion of the world’s population without basic sanitation access by 2015. Graduate student Fry, the lead author of the article, recently completed a Peace Corps Master's in Environmental Engineering, after serving as a volunteer in Cameroon, and is now pursing a doctorate in environmental engineering.
Their paper, "Water- and Nonwater-related Challenges of Achieving Global Sanitation Coverage," was published in volume 42, number 12 of Environmental Science and Technology and is available at http://pubs.acs.org/cgi-bin/abstract.cgi/esthag/2008/42/i12/abs/es7025856.html . A feature on their work "Why is Global Sanitation So Elusive?" appears in the journal's Policy News section at http://pubs.acs.org/subscribe/journals/esthag-w/2008/jun/policy/cc_mdg.html .