Editor’s note: The Development Set is devoting this week to stories of toilets and everything that happens in them. Because, as my favorite children’s book reminds us, everyone poops.

For 14 years, 40-year old Marline Jean did not have a toilet in her home. When she needed to relieve herself, she used one of the methods popular among toilet-less Cap-Haitien residents. Some days, when she was in a public setting, she would get to use a pit latrine, similar to one you may find at a campsite. Other times, she would find a quiet spot in a field. When she was running short on time, she’d use a “flying toilet,” meaning that she’d throw an excrement-filled plastic bag into ditches or trash piles.

Now, Jean climbs the wooden ladder to her concrete roof to find a porta-potty encased in blue plastic. Ten feet away, her vegetable garden is in full bloom, thanks to the minerals created from human compost. Jean’s toilet, like hundreds of others in the city, is part of a program that turns urine and feces safe for reuse as agricultural manure.

The use of human waste as compost may first give pause — but to Jean, it’s a minor miracle. “Everyone who comes here and goes to use the toilet always has a lot of questions about it,” she said. “Some don’t even believe that this is possible.”

A young woman exits a SOIL public toilet in the impoverished community of Shada, Cap-Haitien.

EEven in the Haitian capital 150 miles away, less than a third of metropolitan Port-au-Prince’s three million residents have access to improved sanitation facilities.

The problem with poor sanitation is that it piles up. Plastic bags burst open and poorly maintained latrines overflow. Human waste clogs drainage canals. When it rains, as it often does suddenly and heavily in Haiti, a slow river of sludge spills onto the streets.

Even if a home has a toilet, the city’s sanitation system isn’t equipped to handle the waste that flows through it. “When I first came to Haiti, I stayed in a home that had an actual toilet, but the only way it could be flushed was by pouring water from a bucket directly into the bowl,” said Joanne Gaillard, a humanitarian worker. “The toilet was usually flushed once a day.” Underground sanitation workers called bayakou need to de-sludge latrines and septic pipes underneath homes like Gaillard’s. It’s a stigmatized but necessary job that, until recently, went unregulated.

Most waste in Haiti ends up in rivers, untreated and sometimes contaminated — such as with cholera, which swept through the fragile country in 2010, ten months after a massive earthquake killed approximately 300,000 people and displaced another 1.5 million.

“Cholera is a disease that causes severe, watery diarrhea,” said Dr. Edward Ryan, director of the Tropical and Geographic Medicine Center at Massachusetts General Hospital. “When the person has the diarrhea, the stool that comes out is heavily laden with millions and millions of the bacteria that cause the infection. If that diarrhea contaminates something else, whether it’s the water supply or food supply, then that’s the way cholera spreads.”

Haiti’s outbreak was traced to inadequate and poorly maintained toilets in a United Nations Nepalese peacekeeping camp in the mountain town of Mirabalais. The bacteria-laden fecal matter leaked into the Meille River, eventually flowing into one of Haiti’s main waterways.

8,500 people died during the outbreak, and it continued to infect an average of 385 people per week during 2014. “At the end of the day, it’s a sin that anybody dies of cholera because it means that some very basic sanitation and water metrics were not met,” said Dr. Ryan.