Once a month, John Ebiwari drags an iron rake through the open sewer that runs in front of his house in Nigeria's sprawling commercial capital of Lagos and scoops out the discarded plastic bags that block the flow of bubbling black filth.
On the last Saturday of each month Lagos police officers armed with big sticks make sure residents fulfill their legal duty and clean up their neighborhoods for 'Sanitation Day.'
The clean up provides a minimum of order in Lagos. But, in a move more drastic than seen in most Western countries, several African nations are tackling the scourge by banning or restricting use of plastic bags.
The United Nations estimates that only 10 percent of rubbish in Africa makes it to dumps, with the rest left to rot in communities or burned in acrid bonfires.
As Africans increasingly live in cities, waste management has become a real development problem.
Rwanda, Tanzania, and Uganda have passed laws banning or restricting the use of a main culprit: the ordinary plastic grocery bag.
By the end of the year, Kenya is expected to follow suit.
More than 48 million plastic bags are produced in Kenya each year, according to the UN.
"We need to ban these flimsy plastic bags, which we only use once and dispose of, because all of them make their way into the environment," says environmentalist Joseph Gondi of Kenya's prominent Green Belt Movement, founded by 2004 Nobel Peace Prize winner Wangari Maathai. "You may collect them and say you are taking them to the dump site, but we do not have well managed landfill sites here in Kenya."
The bags are more than a nuisance. Blocked sewers help spread disease. Farmers complain that precious livestock are choking to death on plastic bags, ruining their livelihoods, while rubbish-strewn streets and countryside are counter-productive for Kenya's tourism-based economy.
A clean-up is under way. Five years ago the downtown area of Kenya's capital Nairobi was dirty and unkempt, say residents.
But an army of street cleaners, lots of new litter bins, and a tree-planting program – spearheaded by the Green Belt Movement – have had a dramatic impact for the better.
The government has already passed legislation that will usher in a 120 percent tax on plastic carrier bags and packaging, and a ban on plastic bags less than 30 micrometers thick.
On the outskirts of the spruced-up city center, well away from the safari routes of khaki-clad tourists, most of Nairobi's 3 million residents live in slums.
"Plastic bags are a big problem, one of our worst in life today," says Khamasi Josephat Bandi who lives and works for a small charity in Nairobi's Kibera slum. He supports the proposed ban, and deep among the tin shacks, where pit latrines empty into a broad sewage channel, it's easy to see why.
The channel, which before it became clogged with rubbish was regularly flushed clean by rain, is a stomach churning mass of feces and plastic bags. When the rains come, standing water is a breeding ground for malarial mosquitoes.
"Plastic bags only recently came to Kenya," says Gondi. "Only 15 years ago, women shopped with baskets, and I remember buying fish and sweet potatoes wrapped in banana leaves, not a flimsy plastic bag."
In Nigeria, where plastic bags are legal, women prepare and sell food that customers take away in plastic bags so thin many items have to be double wrapped.
The only affordable clean drinking water comes in plastic sachets, too. Deola Asabia, who runs an environmental charity in Lagos, says there is little hope of a ban on plastic bags in Nigeria until the population has access to clean drinking water.
"The government realizes that they can't get rid of plastic bags," says Mr. Asabia, because without access to clean drinking water "people would be up in arms."
Asabia and other members of her church have set up a charity called Changing Our World Foundation, which has adopted the Obalende neighborhood of Lagos, where Ebiwari was cleaning.
With sponsorship from a local bank and cooperation with the Lagos State Waste Management Authority, they're making sure that Sanitation Day is as widely adhered to as possible.