1. Governance
November 21, 2014updated 29 Jul 2021 11:40am

Sao Paulo combats crippling water shortage

By Drew Reed

Brazil is known for many things: football stars, samba, its powerful alcoholic beverage known as “cachaça”, and of course, the vast green expanses of the Amazon Rainforest. But in Sao Paulo, a different image is emerging in the face of the region’s prolonged drought: bone-dry reservoirs and an alarming water crisis that threatens the city’s residents.

Sao Paulo faced a severe drought in 1930, and another in 1953. The latter create the political pressure to build the Cantareira reservoir system, which was completed in 1976, and which today supplies half of the water used by the city’s residents. That system helped lay the groundwork for Sao Paulo’s explosive growth, taking it from 2m people in 1950 to over 11m in the city proper today, and nearly 22 million in the metropolitan area. The system helped to stabilise the water supply for the growing city. But the additional residents also made the city more vulnerable to future droughts.

The current crisis early this year. By February, officials at Sabesp, the company responsible for the city’s water management in Sao Paulo, were aware that rainfall during the previous few months was much less than normal: water reserves in the Cantareira system had already dropped to 16 per cent of full levels, meaning that further drought could wipe out the system’s reserves entirely. The company, in conjunction with Brazil’s National Water Agency, began offering clients an incentive: use 20 per cent less water, and be charged 30 per cent less than the regular rate.

Despite these efforts, the water shortage only intensified. Later that month, the international press began to take notice, initially in the form of a Bloomberg report on the threat the drought posed for Sabesp. Rain levels remained low, sparking concerns as the World Cup kicked off. And a graph produced by the newspaper Estado do Sao Paulo in May showed that plummeting rain levels have decimated Sao Paulo’s reservoir supply.

By the time Brazil’s presidential elections were held in October, the water levels in the Cantareira system had dropped to 11.9%, and shortages quickly became a hot topic during the election. Incumbent Dilma Rousseff didn’t hesitate to attack her opponent Aécio Neves, a member of the party governing the state, for poor management of the region’s water supply.

The months from November to March, summer in Sao Paulo, traditionally bring the strongest rains of the year. Nevertheless, doubts remain as to whether the critical Cantareira system can be replenished. Even after the city was in early November by a rainstorm so severe that it closed freeways and crippled bus service, reservoir levels didn’t rise: quite the opposite. Experts estimate a rainfall of 65 per cent of average levels during the coming months: that promises temporary relief, but threatens an even worse crisis next year.

These drought patterns are part of an increasingly unstable climatic situation affecting Brazil and the rest of South America. According to data released by NOAA, the US weather agency, rainfall is down in Sao Paulo, in some regions only reaching 25% of its average levels. However, in the Brazilian regions of Minas Gerais and Mato Grosso do Sul, as well as in Paraguay, rain levels are much higher than normal. These changes can perhaps be attributed to global climate change, though a recent report in The Guardian suggests that climate shifts may be made particularly acute in South America due to deforestation in the Amazon.

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The drought has revealed the difficulty of managing the water supply in a region like Sao Paulo. According to a Vox, climate scientist Marcos Heil Costa has found that, “No city in southeast Brazil seems prepared to handle a drought like this one. It is a mix of a lack of preparation for low levels of rain and a lack of environmental education in the population.” Further complicating the issue is the fact that consumption patterns by users remain the same. According to Costa, “Most people continue to use water as if we were in a normal year.”

At this point, no clear solution is in sight. Proposals have been made to replenish the nearly empty Cantareira system with water from the Paraiba do Sul watershed – but that idea has been opposed by officials in Rio de Janeiro, who rely on it for their own water supply. And systems such as desalination, long used in Israel and being implemented by several coastal cities in drought-stricken California, make less sense in Sao Paulo. Though close to the ocean, it is 2,500 feet (760m) above sea level, meaning that transferring purified ocean water to the city would be energy intensive.

Sabesp has been reluctant to impose rationing, though many fear that might be next. In the meantime, a group of NGOs has formed to find a way out of the region’s shortage. Dubbing themselves the “Alliance for Water”, the group is composed of members from 60 municipalities in the region. So far, they have proposed strategies such as the restructuring of water management agencies, fines for users who exceed set water limits, and the preservation of fresh water springs. The group’s leader, Maruissa Whatley, also hopes to raise water levels in the Cantareira system back to at least 15 per cent by next April.

Nevertheless, the city’s future will depend on the amount of rainfall it receives during the next few months. And at this point, the possibility that the drought will continue into 2015 remains a disturbing possibility.  

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