In Brazil, municipalities are legally responsible for urban management and for guaranteeing sanitation infrastructure for citizens.

In big cities like Rio de Janeiro, irregular house construction takes place in some areas despite a lack of permits, and the public administration is unable to prevent the emergence of favelas.

Once a favela is populated with hundreds of families, it is very difficult to remove them. The most sensible solution for sustainable urban development is to create adequate urban infrastructure for the areas concerned, especially in those areas that have regularly seen flooding in the past.

Due to its geography and climate, Rio de Janeiro often suffers from the risks of heavy rain and flooding, especially in summer.

Climate change is making extreme events more frequent and more severe. This causes significant material damage and risks for the population.

Eduardo Paes was already mayor of Rio de Janeiro from 1 January 2009 to 31 December 2016. Since his re-election on 1 January 2021, the Bairro Maravilha programme has been resumed and he has promoted it vigorously.

Under the programme, the municipal departments for nature conservation, finance, infrastructure and sports, as well as agencies such as Comlurb and Rioluz, are working closely together. Roads are being paved, safe pavements constructed, and drainage channels installed and connected to the city's network. Public spaces are being redesigned with outdoor gyms for adults and the elderly, as well as sports fields and playgrounds for children. Streets and squares are being greened, avenues created and benches installed. New LED lighting will enable citizens to use the new public spaces safely, even at night.

For this urban regeneration work, up to 90% of the workers are recruited from the neighbourhoods themselves. This public investment thus not only creates local jobs and income that benefit the local economy. It also increases the quality of work–- as workers design their own neighbourhoods, and local expertise is integrated. This also makes it more likely that the public spaces will be better maintained. Local people will also be able to support workers performing maintenance work on the drainage system, as these citizens know the system.

In some cases, informal development is so poorly structured that it is impossible to implement the programme without relocating people and redeveloping neighbourhoods. In such cases, housing is built on immediately adjacent land so that families do not have to live far from their previous neighbourhoods, schools and workplaces. This process takes place in small units and several cascades. Here is an example. First of all, on a site 'A' 100 housing units are created for about 400 people. People from an immediately neighbouring area 'B' are relocated there. The area that has become vacant is then completely rehabilitated and redeveloped. People from an immediately adjacent area 'C' are then relocated to area B, so that area C can now also be fully rehabilitated and redeveloped, and so on. In this way, poorly developed neighbourhoods can be rehabilitated in a way that is accepted by citizens.

The Bairro Maravilha programme is quite a success, and is transferable to other cities. Besides the direct support from the mayor, and interdepartmental cooperation in the city administration during implementation, the participation of citizens from the neighbourhoods in planning and implementing the redevelopment projects is a crucial factor enabling their sustainable management.