The most populous state in Brazil, São Paulo, is going through its worst water crisis in decades. The summer season, the driest in 84 years, has triggered a drought that has hit 70 cities so far, affecting the lives of 13.8 million people .
From those cities, 38 have started a water rationing plan, where the supply is alternated between neighborhoods every week. One of the most concerning situations, however, is in São Paulo city, the state capital and Latin America’s largest metropolis. The Cantareira System, a four-lake complex of reservoirs responsible for providing water to 45 percent of the city’s metropolitan area (about 6.5 million people) and other surrounding cities, is now running at record lows of 4.1 percent of its total capacity .
In spite of that, for months the state government and Sabesp, the state utility that manages the Cantareira System, have denied the risk of a water shortage in the capital  and the need to enact a rationing plan, like other cities have done. But since earlier this year people from several neighborhoods in São Paulo have been complaining about weekly or even daily interruptions. Just this week, 34 public schools in the city have had problems with the water supply  – and at least one had to cancel classes because of it.
Some people believe they're going through unofficial rationing. On the website Faltou Água  (Water was missing), a collaborative map shows locations where users have reported interruptions to their water supply.
Below is a selection of the messages posted to the website in August and September:
Corte de agua das 00:00 as 6:30 no jardim sao paulo zn de sp. Acontece a pelo menos 1 semana”
Water interruption from midnight to 6 a.m. at Jardim São Paulo, North Zone. Has been happening at least for a week
Aqui na Vl Monumento falta água toda noite, começou faltando à partir das 0h depois foi aumentando o período, hoje dá 21h e já não tem mais água.
Here in VI Monumento there are interruptions every night. It started at midnight but they have been cutting it off it earlier every day. Today beginning at 9 p.m. there's no water anymore
Na v Madalena cortam todas as noites. Isso faz quase 2 meses
In Vila Madalena they have been cutting it off every night for the past two months
Still, many people in São Paulo haven't experienced any problems with their supply. For that, Vinícius Duarte has an interesting theory, which he posted on Facebook :
Boa parte da população paulistana AINDA não sente a falta d'água (e acredita no governo, e continua gastando a rodo, e fazem piadinha com o tema) por uma razão simples: mora em prédio de apartamentos. Quando a Sabesp desliga o fornecimento (todo dia), o morador não vê a torneira seca e fica tranquilão. Afinal, ela continua a ser abastecida pela caixa d'água do edifício, que é coletiva. (…) Como algumas unidades consomem menos que outras, a coisa vai meio que se compensando. Mas isso só enquanto TEM água na caixa.
Most of the population of the city of São Paulo STILL doesn't feel the water shortage (and believes in the state government, and keeps wasting water and making jokes on the subject) for a simple reason: they live in apartment buildings. When Sabesp cuts off the supply (every day), they keep getting water from their taps and think it's all good. But this water is coming from the building's water tower, which is collective. As some apartments use less water than others, they naturally compensate each other. But that will last only if there's still water in the collective tank.
Cantareira System on the verge of collapse
It was revealed this week by the State Prosecutor’s Office that Sabesp knew the reservoirs were at risk of water shortage since 2012 . At that time, the company had sent a report to its investors in New York – it has 25.4 percent of its shares negotiated at the New York Stock Exchange – warning that a drought predicted for April 2014 might impact its finances. Sabesp, however, only decided to take measures about eight months ago : a discount to users who saved water was its main strategy to combat the imminent collapse of its main reservoir.
Since May, the company has been using the first quota of the “dead volume” (the remnants of water that lie in the bottom of the lake). Regulators had prohibited it from collecting from the second quota of that volume over concerns it was mismanaging supplies, but that decision was revoked yesterday due to the emergency of the situation , since the first quota will only last for the next few weeks.
The second quota comprises of 106 billion liters and should last until March 2015 without water rationing. After that, it is over: there is no “third” dead volume quota at the Cantareira. All there is left is to hope that the rainfall during the wet season, which peaks in December through February, will be enough to provide more water for the rest of 2015.
As blogger Camilla Pavanelli put it for her 1,600+ followers on Facebook :
O plano do governo do estado é um só: captar até a última gota de volume morto e torcer para que chova. Não há plano B. Sendo assim, eu diria que já passou a hora de reconhecermos o seguinte: O tempo de pensar no uso racional e consciente de água já passou. O assunto, agora, é outro. O assunto não é “usar com parcimônia para que não acabe”. O assunto é que está acabando – ou, se considerarmos que a água do Sistema Cantareira que estamos consumindo é volume morto, já acabou.
The state government's plan is only this: to drain the reservoirs until the last drop and to pray it will rain. There is no plan B. That being said, I think it's time we recognize something: the time to think about the rational and conscious use of water is over. That ship has sailed. The main discussion now is not “use it wisely so it won't end”. It is ending nonetheless – or, if we consider we've been consuming the “dead volume” water, it has ended already.
Specialists believe it’ll take at least four years for the system to return to normalcy , but that estimate depends on rainfall meeting historical averages. The main construction plans to start draining water from other rivers and reservoirs in the country are only due to be ready in 2016, according to Sabesp’s own schedule.
In the countryside
There are 38 municipalities in the countryside who are going through official water rationing. Those cities are not attended by Sabesp, but rather have their water supplied by small, local companies.
The main advantage of going through an official rationing is that people are able to know when and at what time they’ll have their water interrupted – so they can take precautions and are not caught by surprise.
That doesn’t necessarily prevent rallies and revolts, though. Itu, a city with 163,000 inhabitants, has experienced rationing since February and has been supplied poorly, with the district having to buy 3 million liters of water daily from nearby cities. On Sunday, residents attended a fourth rally against the water shortage , blocking a highway and setting fire to a bus.