Residents association president Otavio Alves Barros walks by the sewage treatment Biosystem of the Enchanted Valley sustainable community on the outskirts of Tijuca National Forest in Rio de Janeiro, Brazil, Monday, June 6, 2022. Electricity arrived in the late 20th century to the low-income Enchanted Valley community, but the utility never connected it to the city’s sewage network, so its residents set out to solve the problem on its own by building a biodigester and artificial wetland to process all sewage generated by all of its 40 families.