Sao Paulo. The largest city in South America and home to 12 million people. ©Scott Warren

Last March, one of Brazil’s most important newspapers, O Estado de S. Paulo, published a version of the article below, which summarizes the Conservancy’s efforts to help secure Sao Paulo’s water supply. It is translated and reprinted here with permission.

By João Campari and Samuel Barrêto, The Nature Conservancy

The inhabitants of Sao Paulo have been dealing with discouraging images of cracked riverbeds where they used to see flowing water, making this temperate part of Brazil look more like the country’s semi-arid region. Unfortunately, these stark images show the worsening struggles of the Cantareira system, one of the greatest water supply systems in the world.

Right now, the Cantareira’s reservoirs — responsible for providing water for more than 12 million inhabitants of the Sao Paulo Metropolitan Region (RMSP) and Campinas — are operating at less than 15% capacity*, the lowest level recorded since the Cantareira’s creation in the early 1970s.

The images, the symbol of the current crisis, show that water doesn’t really come from the taps in our houses. It comes from nature, and in Sao Paulo much of that nature is the Atlantic Forest. While water rationing gets peoples’ attention and is one of the necessary responses to water scarcity, rationing alone is not enough to solve the long-term problem of securing lasting access to fresh water.

We must look beyond the tap and work to take care of our water supplies at their sources. We need a systemic response for the management of watersheds to restore the sources of our water that have been degraded, polluted and deforested. Forests are very important for healthy fresh water supplies. Unfortunately, the Cantareira system alone has lost 70% of its original forest cover, aggravating the sedimentation of rivers and dams, and decreasing their ability to supply water. The degradation of native vegetation also worsens the effects of erosion and drought.

The interaction of all these factors — deforestation, sedimentation, erosion and drought — leads to a situation of extreme risk and represents an environmental, social and economic threat not just to Sao Paulo, but to the entire country of Brazil. The Sao Paulo Metropolitan Region and Campinas together are responsible for more then 22% of the country’s GDP. Therefore, it is a priority to create a strong and strategic response to the increasing and urgent problems of water quantity, quality, access and supply for urban centers.

 Protecting Water Supplies at their Sources

We must go beyond conventional interventions, such as engineering works — more dams or aqueducts are not the answer. Wider, systemic responses are necessary, and the responsibility to act is not limited to the government. We all need water and it is the shared responsibility of businesses, communities and civil society as a whole to search for solutions together. The government’s role is to foster and implement multiple solutions that reach multiple stakeholders at once.

Deforestation of the Atlantic Forest contributes to Sao Paulo's water woes. © Scott Warren
Deforestation of the Atlantic Forest contributes to Sao Paulo’s water woes. © Scott Warren

The Conservancy’s work shows that one of the highest priorities for securing Sao Paulo’s water supplies is strengthening the Cantareira system’s “green infrastructure” by restoring the degraded forests of the Atlantic Forest, as well as conserving existing forest remnants. Such initiatives ensure the health of a watershed. This type of solution, when well managed, minimizes the risk of extreme events and reduces the vulnerability of populations to floods and prolonged droughts. Healthy forests also store water and reduce erosion and provide environmental services of water regulation and security to the population.

New York City illustrates this equation quite clearly. Decades ago, the city’s administration compared the costs of both natural and built infrastructure for protecting and providing water. Preserving the forests that were source of the city’s drinking water cost US $1 to 1.5 billion over 10 years. That amount was seven times less than the estimated US $6 to 8 billion needed to build a traditional, engineered water treatment and distribution network. (That amount doesn’t include the additional and ongoing operational and maintenance costs of $300 to $500 million a year that would have been necessary.) Obviously, nature was the better buy for the people of New York.

It is something for Sao Paulo to consider. A recent study by the Conservancy showed that restoring about 35,000 acres of deforested areas and preventing erosion on 5000 acres within the basins of the Piracicaba, Capivari, Jundiaí and Alto Tietê rivers would decrease the level of sediments that clog the rivers by 50%. Reducing erosion would increase the capacity of water reservoirs and simultaneously decrease the cost of treatment for the removal of sediments.

What the Conservancy is doing in Sao Paulo

To help accomplish restoration goals in the lands around Sao Paulo’s Cantareira system, the Conservancy-led Water Producers Project provides payments to farmers and ranchers who conserve forests on properties that are part of the watershed that feeds the Cantareira reservoirs. This payment-for-environmental-services program recognizes and compensates landowners for the water-producing value their lands provide.

The Conservancy also leads the Water for Sao Paulo Movement. This initiative fosters conversation and working relationships between different stakeholders and focuses on the importance of both water conservation and nature-based solutions for securing the water supply of the region. Because healthy forests are so important for healthy rivers and water supplies, Water for Sao Paulo seeks to restore degraded forests near the urban area.

 Finally, Sao Paulo must strengthen the existing Watersheds Committees. Created by the Brazilian Legislature, Watersheds Committees discuss and make decisions about the use of water from specific river basins and are some of the most important collaborations for achieving a balance between water supply and demand. Committees include representatives of local governments, water supply companies and civil society, who are responsible for tasks such as approving water management plans, defining actions for conservation of biodiversity and mediating conflicts about the use of water resources. There are more than 200 of these groups in Brazil.

The current crisis in the Cantareira system is both a challenge and an opportunity to learn from the past and make better decisions for the future. If we have the discernment to act in a systemic way and the political and institutional capacity for change, we will be able to reduce the risks of a permanent cycle of water shortage. In addition to this, we have the opportunity to show how healthy watersheds contribute to water security, which is indispensable for Sao Paulo’s social and economic stability into the future.

To learn more about how the Conservancy is helping to secure Brazil’s water supplies, please visit Where Does Your Water Come From?

*Since this article was published in March, the need for concerted action in Sao Paulo has become even more urgent. The level of water in the Cantareira system has now dropped – to about 8% of its overall capacity. As an emergency stopgap to provide water to the city, the government of Sao Paulo spent US$36 million on emergency constructions to allow access to water stored below the level of the pumps. Known to water managers as “dead volume,” this water was never intended to be part of the water supply, and the reservoirs are now, essentially, operating at a deficit.

 Though this emergency step expanded the available water level to around 27% of the capacity of the system, the largest city in South America is still at risk. Water managers also stress that the use of the dead volume will postpone the recovery of the Cantareira system’s reservoirs, once the rainy season starts in October, which means that the immediate water security crisis in Sao Paulo will likely last for many more months.

 For ways you can help restore the Atlantic Forest and contribute to Sao Paulo’s water security, please visit Plant-a-Billion Trees

João Campari has a PhD in Environmental Economy and is the director of the Conservancy’s conservation programs in Brazil.

Samuel Barrêto is a specialist in Water Resources and coordinator of the Conservancy’s Water for Sao Paulo Movement (MApSP).

 Opinions expressed on TALK and in any corresponding comments are the personal opinions of the original authors and do not necessarily reflect the views of The Nature Conservancy.


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