A significant percentage of these deaths could be prevented through proper sanitation, good hygiene, and safe drinking water, according to the WHO. Many people around the world, however, do not have access to centralised sewer networks that help improve sanitation.
In Dakar, Senegal, only a small fraction of the population - wealthy residents and people in commercial areas - have access to sewer networks. Middle- and low-income residents often flush poop into septic tanks that can be emptied in two ways: paying someone to shovel the waste into a bucket that gets dumped onto the street, or hiring a truck driver to take the poop to a treatment centre.
Manual emptying costs roughly half as much as the truck service, and residents can remove the waste themselves. But leaving the poop outside can make people ill; University of Virginia professor Molly Lipscomb, who researches how developing countries adapt to a lack of centralised sanitation services, told Business Insider that the poop puts people at risk of diseases, especially children who play on the street.
Hiring a truck driver, meanwhile, is a pricey route that many residents avoid.
In an attempt to improve the system, Senegal's government invited Lipscomb and a team of researchers to Dakar, the country's capital. Lipscomb, who began working with Senegal's national sanitation office in 2011, said she wanted to increase the number of people using the mechanical desludging service, but decided against recommending the addition of more trucks.
There are about 120 desludging trucks in Dakar, which is likely enough to accommodate requests if all residents used the mechanical service, Lipscomb said. As of 2015, however, only 50% of people in the capital relied on truck drivers.
"The trucks actually have a lot of excess capacity right now," Lipscomb said. "So you can find trucks that are sort of hanging around not doing a lot of work, or just between jobs, pretty easily."
On top of that, owning a truck comes with a significant entry barrier, as each vehicle costs between $40,000 (about R570,000) and $60,000 (R866,000-odd) Lipscomb said.
Lipscomb's team turned to cellphones and came up with a system for residents to order a desludging truck via text message. A call centre would hold an auction where truck drivers compete to claim a resident's desludging request - a process that helps bring the service's cost down.
NPR referred to Lipscomb's idea as "Uber for Poop."
Previously, Lipscomb said, wealthier households paid more for the mechanical service because truck drivers set prices based on what they expected residents to be able to pay.
The truck drivers have not engaged with the call centre format equally, Lipscomb said, but some have participated actively in the auctions. She added that prices have gone down about 7% due to the auctions.
"It does look like people who call in are the slightly more wealthy households that would probably be price discriminated against in the market," she said.
Lipscomb said she and her team - Terence Johnson at the University of Notre Dame, Laura Schechter at the University of Wisconsin-Madison, and Jean-Francois Houde at the University of Wisconsin-Madison - did not set out to oversee the system long-term. The professors worked with an NGO and handed the project off to Senegal's government after finishing their research in 2016.
In April 2018, the government decided to put a private company in control of the auctions, Lipscomb said. The Senegalese company Delvic Sanitation Initiatives is set to restart the system in January 2019.
Lipscomb is still in contact with Delvic and said her team is continuing to examine how to improve the sanitation system. The call centre system only covers Dakar right now, though Delvic may choose to expand in the future, Lipscomb said.
"[Delvic] actually substantially improved the treatment centres when they were privatised," Lipscomb said. "We can see that through the quantity of sludge going through these treatment centres. So we expect that the call centre will do very well under them."
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