Most Haitians are forced to dispose of their waste in waterways, plastic bags, or even abandoned buildings, according to SOIL. Any existing toilets are often poorly designed, with waste flushing straight into rivers or groundwater.
Such practices mean that human feces easily get into the water supply, which can cause waterborne diseases such as cholera, currently at epidemic levels in the country, according to the U.S. Centers for Disease Control and Prevention.
More than 6,000 people have died and 420,000 have been sickened since cholera broke out in Haiti in October 2010.
"Sanitation was the most successful health intervention in the modern world," said SOIL co-founder and soil ecologist Sasha Kramer. But in Haiti, "poop getting into water is the leading cause of death."
So far, SOIL has installed ecological toilets in camps of more than 20,000 people left homeless by the 2010 earthquake in Port-au-Prince. Facilities are also being supplied to 30 communities in northern Haiti.
But these aren't just any toilets: Kramer and her colleagues constructed urine-diverting toilets, a type of ecological sanitation in which urine and feces are separated. The waste is then covered with a dry material to aid decomposition and is regularly collected.
"With seven billion people on the planet as of this week," Kramer said, "technologies like this are more and more important for addressing the basic rights of a growing population and reducing the negative impact on the earth's ecological systems."