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Futuristic toilets offer sanitation to world’s poor, water savings everywhere

Photo by Michael Hanson/The Bill & Melinda Gates Foundation
Bill Gates, center, with a researcher from California Institute of Technology at the Reinvent the Toilet Fair in Seattle.

Given his steady and persuasive advocacy of the waterless urinal, I feel sure that Don Shelby would be all over this story were he still blogging for MinnPost. So, on Don’s behalf, I am pleased and proud to cast Earth Journal’s little spotlight on last week’s “Reinvent the Toilet Fair.”

Sponsored by the Bill and Melinda Gates Foundation, the Seattle event put on public view the results of a big-money challenge to develop low-cost, high-quality toilets that handle both liquid and solid waste without connections to a water system, an electric grid or a sewer line. Another critical parameter: operating costs below 5 cents a day.

The objective is not to replace the massively wasteful flush toilets of the industrialized world – not yet, anyway – but to extend the benefits of modern sanitation throughout a developing world whose facilities run the sorry gamut from an outhouse downhill to a ditch.

According to a report in National Public Radio’s Shots blog, where I first spotted this news, the Gates foundation has granted nearly $150 million over the last two years to improve global sanitation, with at least that much yet to come. It’s a major initiative for the foundation, alongside its philanthropic assaults on malaria and a range of communicable diseases that can be prevented with vaccination. 

In a post on the foundation’s website, titled “Inventing a Toilet for the 21st Century,” Gates wrote:

The flush toilets we use in the wealthy world are irrelevant, impractical and impossible for 40 percent of the global population, because they often don’t have access to water, and sewers, electricity, and sewage treatment systems. Worldwide, there are 2.5 billion people without access to safe sanitation — including 1 billion people who still defecate out in the open and more than 1 billion others who must use pit latrines.

Beyond a question of human dignity, this lack of access also endangers people’s lives, creates an economic and a health burden for poor communities, and hurts the environment.

Food and water tainted with fecal matter causes diarrheal diseases that kill 1.5 million children every year — more than the annual deaths from AIDS and malaria combined. Chronic diarrhea can impact the development of children’s minds, bodies, and immune systems. The consequences are especially stark for women and girls who are often forced to miss work or school when they are menstruating or risk assault when they have to defecate in the open or use public facilities at night.

It was against that backdrop that the Gates Foundation granted $3 million through its “Reinventing the Toilet Challenge” to teams at eight universities around the world. Bloomberg’s Lisa Beyer had the clearest description of the three top winners on display in Seattle last week:

  • The California Institute of Technology won first prize for a device that includes a solar-powered electrochemical reactor that disinfects waste and generates hydrogen to be used as fuel.
  • The model from the U.K.’s Loughborough University generates clean water from urine and feces and uses a hydrothermal carbonization reactor to turn solid waste into biological charcoal that can be used as fertilizer.
  • The University of Toronto entry dries and smolders waste to sanitize it and uses a sand filter and ultra-violet light to recover clean water.

Going forward, the foundation will pursue field testing of these models to determine their real-world viability. It has also opened a second round of the challenge, with grants of $3.4 million supporting these projects:

  • At England’s Cranfield University, an effort to “develop a prototype toilet that removes water from human waste and vaporizes it using a hand-operated vacuum pump and a unique membrane system. The remaining solids are turned into fuel that can also be used as fertilizer. The water vapor is condensed and can be used for washing, or irrigation.”
  • At the multinational Eram Scientific Solutions Private Limited, a project to “make public toilets more accessible to the urban poor via the eco-friendly and hygienic ‘eToilet.’ ”
  • From North Carolina’s RTI International, development of “a self-contained toilet system that disinfects liquid waste and turns solid waste into fuel or electricity through a revolutionary new biomass energy conversion unit.”
  • And from the University of Colorado at Boulder, creation of “a solar toilet that uses concentrated sunlight, directed and focused with a solar dish and concentrator, to disinfect liquid-solid waste and produce biological charcoal (biochar) that can be used as a replacement for wood charcoal or chemical fertilizers.”

For those who like to monetize the paybacks from investing in environmental or social progress, Gates quotes the World Health Organization’s calculation that “improved sanitation delivers up to $9 in social and economic benefits for every $1 invested because it increases productivity, reduces healthcare costs, and prevents illness, disability, and early death.”

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Perhaps it goes without saying, but I’ll say it anyway – sooner or later, these new fixtures ought to have a place in the industrialized world as well.

For the moment, we may feel we’re so awash in drinking water that we can afford to flush it down the drain,  so flush with public money we can keep processing the sewage back to potability, and even rich enough in our rural households to keep building or rebuilding flush-centered septic systems.

But this really is a colossal waste that must catch up with us eventually,  and in more than a few places the time of reckoning could already be drawing near.

Modern sewage-treatment systems aren’t nearly as ubiquitous as flush toilets. In the Land of 10,000 Lakes, for example, more than a half-million existing homes flush their toilets into septic systems, as will one out of four new homes built in the state.

Dan Olson, an information officer with the Minnesota Pollution Control Agency, told me that by the agency’s most recent estimates some 114,000 of these households have systems classed as substandard. Of those, nearly 38,000 are sufficiently substandard to be considered imminent threats to public health.

If those stats strike you as alarming, they actually represent quite a bit of recent progress. Ten years ago, the estimate for out-of-compliance systems was more like 33 percent, and some 60,000 were classed as imminent threats.

Indeed, that situation was a key justification for the not-quite-successful drive in 2005 to have the Legislature enact a statewide Clean Water Legacy fund, financed with an annual $36-per-household “user fee,” to pay for water-quality upgrades that otherwise wouldn’t get done. (Three years later, having morphed into a sales-tax vehicle to support a broader array of programs, the Legacy Amendment was enacted by referendum.)

But the problem is far from solved, and in some cases it may not be solvable with systems centered on a flush toilet. I know a few cabin owners who have purchased composting toilets, or stuck with outhouses, because traditional septic systems were either unaffordable or simply impossible on their particular properties.

I heard about more such cases last weekend, sailing on Lake Pepin. The buzz in our little marina was about all the property owners along the Minnesota shore who are finding they can’t upgrade their septic systems to meet regulations, in some cases because there simply isn’t enough land between the flusher and the lake.

In the short run, it’s easy to imagine a new generation of waterless, self-contained toilets catching on with homeowners in situations like these.

And in the long run, given some of the dire forecasts concerning the fate of the world’s potable-water supplies, it’s not impossible to envision the world’s advanced societies waking up to the folly of using our most essential,  irreplaceable natural resource to flush a bunch of toilets.

  * * *

For those who wonder how these prize-winning alternative toilets are tested for effectiveness, I don’t blame you one bit – and the answer is kind of interesting. It turns out there is at least one company that makes ersatz excrement for this very purpose.

Maximum Performance is its name, and its product is a blend of soybean paste and rice extruded into 350-gram cylinders and distributed, according to NPR, “to nearly all toilet manufacturers around the world for testing purposes.”

Now you know.

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