Friday, November 18, 2011

From Atlanta to Accra: The growing sewage problem

Christine Moe shows the above video, produced by WaterAid, to first-year medical students at Emory. "I want students to think more about sanitation, and to understand why they should care about the enormous problems surrounding it," she says.

By Carol Clark

Christine Moe began researching human waste disposal during the 1980s, as a VISTA volunteer. She was sent to rural West Virginia to assist in coal mining towns that lacked sewage treatment plants.

“The valleys were incredibly steep and narrow, and septic tanks need to have flat land for the drain field,” Moe recalls. “So the septic tank pipes just emptied straight into the creeks. You could see toilet paper in the brush lining the water.”

Moe now works on sanitation projects around the world as a professor at the Rollins School of Public Health and the director of Emory’s Center for Global Safe Water.

November 19 is World Toilet Day, which aims to build awareness that 40 percent of the people on the planet use unsafe toilets or defecate in the open. It’s a fact of growing concern, to both human health and diginity, and to the environment: The developing world is rapidly urbanizing, and raw sewage is building up in high-population centers.

“When I walk through the slums of Accra, Ghana, I get really outraged at the conditions that I see people living in,” Moe says. “That passion motivates me to want to find solutions.”

World Toilet Day may finally gain momentum in the United States, since actor Matt Damon became a celebrity spokesperson for the cause, and the Bill and Melinda Gates Foundation began awarding major grants addressing sanitation.

The Center for Global Safe Water recently received $2.5 million from the Gates Foundation to study ways that people are exposed to human waste in cities of the developing world. The first phase of the research is focusing on Accra, which is typical of many rapidly growing cities in sub-Saharan Africa in its lack of sewage treatment plants. Tanker trucks suck up excreta from latrines and dump it into the coastal ocean.

“You have people literally surrounded by shit,” Moe says.

Public latrines in Accra are squat plates with a trench underneath, shared by hundreds of people. The latrines lack sinks, running water and soap.

People who can’t make it to a latrine may resort to squatting over a plastic bag, then tying up the excreta and tossing it into the household trash, or simply flinging it out a window. This method is known as the “flying toilet.”

Open drains line the unpaved streets where children play. “You’ll see children kicking a ball, and if the ball lands in the drain, one of the kids will climb in, get the ball out and they’ll just keep playing with it,” Moe says, pointing to a photo of a little boy rummaging amid raw sewage in a drain (see above).

Urban agriculture pops up in the slums wherever people can find a spot to grow a few vegetables. For irrigation, they dip containers into the drains and pour the water over the plants.

“There are so many ways that people can be exposed to fecal material, it’s hard to know how to prioritize an intervention,” Moe says. “In our study, we’re trying to get information that will help policy makers develop the most effective solutions.”

The sub-human conditions that Accra slum residents must endure are hard to imagine without seeing them, Moe says. She wants people in Atlanta to not only grasp the terrible toll of poor sanitation in the developing world, but to also understand the growing problem of sewage in the United States.

One-third of the water in a typical U.S. household is used to flush toilets. “We are using drinking water to remove excreta from our homes,” Moe says. “In a city like Atlanta, faced with water shortages every couple of years, I don’t think our system is sustainable.”

The Gates Foundation has launched a campaign called “Reinventing the Toilet.” The idea is to spur innovative toilet designs that do not require massive amounts of water and infrastructure.

China, for instance, is promoting the use of anaerobic digester systems to process waste in rural areas. Household toilets feed into the odorless digesters, which convert the waste into biogas used as an energy source.

“We really need to start getting more creative when it comes to toilets,” Moe says.

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