Latrines Trounce Toilets: barriers to sanitation coverage

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 Technological University.

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.”

Their paper, “Water- and Nonwater-related Challenges of Achieving Global Sanitation Coverage,” was published in volume 42, number 12 of Environmental Science and Technology.  A feature on their work “Why is Global Sanitation So Elusive?” appears in the journal’s Policy News section.

Abstract:

Improved sanitation is considered equally important for public health as is access to improved drinking water. However, the world has been slower to meet the challenge of sanitation provision for the world’s poor. We analyze previously cited barriers to sanitation coverage including inadequate investment, poor or nonexistent policies, governance, too few resources, gender disparities, and water availability. Analysis includes investigation of correlation between indicators of the mentioned barriers and sanitation coverage, correlations among the indicators themselves, and a geospatial assessment of the potential impacts of sanitation technology on global water resources under six scenarios of sanitation technology choice. The challenges studied were found to be significant barriers to sanitation coverage, but water availability was not a primary obstacle at a global scale. Analysis at a 0.5° grid scale shows, however, that water availability is an important barrier to as many as 46 million people, depending on the sanitation technology selected. The majority of these people are urban dwellers in countries where water quality is already poor and may be further degraded by sewering vast populations. Water quality is especially important because this vulnerable population primarily resides in locations that depend on environmental income associated with fish consumption.

Source: Newswise, 17 Jun 2008