How a $42,300 favela in Rio got its clean water back

So the community set out to solve the problem themselves by building a biodigestrator and artificial wetland to process all the wastewater from all of their 40 families.

It began full operations in June and is the first independently built biosystem for an entire Brazilian favela, according to Theresa Williamson, executive director of Catalytic Communities, a nonprofit organization that supports underserved communities. And it could serve as an example for rural hamlets across Brazil. According to official figures, 45% of Brazilian sewage goes uncollected.

The Enchanted Valley project has been in development for years. The president of the residents’ association, Otávio Barros, took a group of tourists to a downhill waterfall in 2007 and when they wanted to bathe in its waters he told them they couldn’t; All of the municipality’s sewage flowed through this cascade. The seed of an idea was planted, however, and he began to drum up support.

“Back then, it was harder to get people’s attention and show that everyone would benefit,” he told The Associated Press as he walked through the community.

He found allies among researchers at the Pontifical Catholic University of Rio de Janeiro, where he had worked as an administrative assistant. They secured money from the Rio State Foundation to support research to complete a first phase in 2015, and more recently from German and Brazilian nonprofit organizations Viva Con Agua and Instituto Clima e Sociedade to provide all households with additional funds Connect from Catalytic Communities.

Barros worked alongside five other neighborhood residents for months, including about three weeks just breaking through rock to make a path for new pipes. They lead to the arched bio-fermenter, where the waste water is absorbed by anaerobic microorganisms. The remaining liquids then meander further beneath the built-up wetland and are cleaned by fertilizing the overlying plants.

The full price of the system was about 220,000 reais ($42,300). That’s a quarter of what it would have cost to run pipes through the forest down to the existing sewage network at sea level, according to Leonardo Adler, founding partner of Taboa Engenharia, which oversaw the technical side of the work.

The federal government has a plan to improve wastewater treatment across Brazil, which it is pursuing through private concessions in large urban areas. But that approach doesn’t help small, isolated communities like Enchanted Valley, where the smell of sewage is now gone and the nearby waterfall is clean for bathing.

“I’m very happy because it was a very arduous phase, getting partners, involving the community to collect the wastewater and return it clean to the environment,” Barros said. “It’s part of a dream coming true. We have others for the Valley.”