How cities treat their rivers

Researchers investigated 16 cities in western São Paulo that originated during the nineteenth-century coffee boom and diagnosed the water courses that supported their creation.

By José Tadeu Arantes

Agência FAPESP – Whether they embellish public parks or are forgotten, silted up and polluted, the rivers of São Paulo State have a great deal to say about the cities established on their banks.

In line with the treatment afforded to the rivers and brooks of the state capital, many cities of the interior have canalized their water courses and hidden them under avenues and other paved areas. They are remembered when the rainy season makes underground galleries overflow, causing floods and subjecting the population to major disruptions.

These were some of the findings of the project “The construction of bottom valley landscaping in Western cities of São Paulo State,” supported by FAPESP.

Led by Norma Regina Truppel Constantino, a professor of architecture and urbanism at São Paulo State’s Bauru campus, where she teaches master’s students, the project investigated 16 cities of western São Paulo that were founded and developed during the coffee boom in the late nineteenth century and the first half of the twentieth.

“Our aim was to find out how the rivers that supported the birth of these cities are seen now by the population, whether they're still important to people, and to what extent they’re taken into consideration by local government, in terms of master plans, legislation passed by the council, and so on,” Constantino told Agência FAPESP.

The project focused on four cities on each of the four railroads that run through the west of the state: Araraquara, São José do Rio Preto, Jales and Santa Fé do Sul on the Araraquarense railroad; Botucatu, Lins, Penápolis and Araçatuba on the Noroeste railroad; Agudos, Lençóis Paulista, Tupã and Panorama on the Alta Paulista railroad; and Avaré, Ourinhos, Presidente Prudente and Presidente Epitácio on the Sorocabana railroad.

Constantino had already studied the history of these cities as part of the Thematic Project “Erudite and technical knowledge in the configuration and reconfiguration of urban space: state of São Paulo, 19th and 20th centuries,” coordinated by historian Maria Stella Bresciani.

“Our survey of the farms that occupied the land on which these cities were built had shown that rivers were always the key elements. Either the town center grew up on the banks of a river or rivers defined the borders of the farms where urbanization began. The new project set out to enrich the historiographical background with a detailed picture of the state of these rivers today. Our in-depth research work involved the participation of four recipients of scientific initiation grants from FAPESP. We identified the problems and investigated the potential integration of these rivers into the urban space,” Constantino said.

Findings

The project served as a basis for the drafting of a type of diagnosis comprising nine topics.

“Some of the cities have maintained the visibility and identity of their rivers, conserving natural features and avoiding environmental degradation. In others, the areas concerned have been landscaped with little environmental impact, allowing the population to enjoy linear parks built along river banks,” according to the diagnosis report.

There are also cities that have master plans calling for conservation of such areas but ignore these guidelines, so that the water courses are degraded, silted up and often polluted by illegal domestic sewage.

Moreover, 12 of the 16 cities studied have canalized parts of their water courses underground. In rainy periods, this causes overflows and flooding.

When parks are created and the vegetation fringing the rivers is rehabilitated, overflows and flooding episodes decrease during the summer when rainfall is especially heavy because properly conserved water courses contribute to urban drainage and parks prevent encroachment and degradation of the adjoining areas.

In cities where the railroad runs along the banks of a river, the water course is derelict and forgotten. Most of São Paulo’s railroads have long been disused owing to the hegemony of the automobile, and these areas are abandoned and degraded, without safety or security for leisure activities.

Another conclusion drawn by the researchers was that, although rivers are a key component of the history of these cities in western São Paulo, most are not highly valued by the locals and play no part in people’s everyday lives. Even bridges affording a view of the rivers are few and far between.

Urban management models are inadequate, they found. Environmental and urban planning laws are not integrated.

“People won’t value their rivers without education and awareness raising,” the diagnosis report concludes. “Participatory planning must be developed to decide how to develop the areas concerned. Merely legislating and introducing regulatory frameworks is not sufficient.”

Hidden rivers

Canalization of rivers and streams is one of the most serious problems, according to Constantino. In these cases, the cities of the interior have followed the model that was adopted in the state capital and is now heavily criticized by the experts.

“There was no canalization in only five of the 16 cities we studied: Panorama, Lençóis Paulista, Botucatu, Avaré, and Presidente Epitácio. In Panorama and Presidente Epitácio, in fact, canalization isn’t possible because the river there is the Paraná,” Constantino said.

“What is most surprising is that in several cases public parks were built over the canalized rivers. Instead of running through the parks and being enjoyed by the public, they’re buried and hidden away underground.”

One positive point is that almost all these cities have no illegal sewers. With the sole exceptions of Agudos and Ourinhos, they all treat domestic waste before disposing of it in the rivers.

According to Constantino, there are significant opportunities for improvement. Like all 645 cities in the state, these 16 are participants in the São Paulo State Department of the Environment’s “GreenBlue City” program (Município VerdeAzul), which establishes ten environmental management guidelines covering sewage treatment, solid waste, biodiversity, urban tree planting, environmental education, sustainability, water management, air quality, environmental structure, and environmental councils. Three of the 16 ranked among the program’s top ten in 2014: Botucatu came first, Lençóis Paulista seventh, and Araraquara eighth.

“Rivers should be visible,” Constantino said. “If people see their rivers, they value them and are prepared to do something about conserving them.”

“In Lençóis Paulista, Panorama, Avaré, Presidente Epitácio and São José do Rio Preto, this visibility is very evident. In São José do Rio Preto, in fact, we can see both sides of the situation. The city began between two streams, the Borá and the Canela, which are now totally canalized and run underground beneath broad boulevards. But they’re affluents of the Preto River, which has been dammed to form a lake in a much-visited park that’s highly appreciated by the locals.”

The team included the following FAPESP grantees: Júlia Marcilio Torres, Maria Olívia Simões, Marília Lucena de Queiroz, and Raisa Ribeiro da Rocha Reis.