Sabesp can adopt trundle five days without water per week if rainfall does not increase the Cantareira System, said the metropolitan director of the company, Paul Massato Yoshimoto, visiting Suzano, next to the governor of São Paulo, Geraldo Alckmin (PSDB). The measure would be adopted in extreme situation.
“The conceptual theoretical calculation to reduce 15 cubic meters per second in the Cantareira need a caster two days with water for five days without water. If necessary, not to reach zero at the dam, not having any more water to distribute, there on the edge, if the works had not moved at the speed we are planning, we can take the risk of a drastic rotation, “said the director.
Yoshimoto said on Tuesday (27) that the measure can complement measures already adopted, such as reducing pressure and application for reduction of consumption by the population.
At the event, Alckmin gave no statements on the rotation. The governor spoke of the transfer of Guaratuba River to the Alto Tietê system and the transfer of works of water Billings Dam.
According Massato, the implementation of the measure will depend on the analysis of regulardores bodies of water.
“If the National Water Agency (ANA), the Department of Water and Power (Daee), which are regulators of water resources, they conclude in their studies that Sabesp have to take much less than it is withdrawing the Cantareira, the solution would be to limit the deployment of a very drastic rotation, “Yoshimoto said.
The director did not make predictions about when the rotation could start to be adopted.
“They (regulators) is defining the water withdrawals of Cantareira. We still have an expectation, small, but we hope that the summer rains come back,” said Massato.
The rains accumulated this month in Cantareira System represent 49.5% of the historical average (see chart below).
ANA ruled last week that Sabesp further reduces the uptake of Cantareira, leading the company to adopt the goal of reaching the withdrawal of 13 cubic meters per second, and still operated on Tuesday 16 cubic meters. To Massato, the implementation of rotation 5×2 is required if the limit is even lower.
“If we have to take a 10, 12 cubic meters per second, it would be necessary to implement trundle two days with water five days without water. The equivalent of that to have an economy needed there in Cantareira and not let [the level] keep falling. ”
The director believes that the measures already adopted managed to reduce the flow of Cantareira.
“With this technology, with the accession of the population by reducing consumption and more transfers [of other tanks], we were producing in Cantareira 32 cubic meters per second. Today we are producing 16.5 cubic meters per second. So to make a rotation, we would have to make a very heavy rotation. If the rains persist in not falling into the Cantareira system, would be a solution of a heavy rotation, too drastic. ”
Most critical year
The director of Sabesp said the initial planning for the lack of water began in December 2013 and that was avoided that water shortages have occurred in the past year.
“What was our planning? What from October, in the spring, occurred at least the minimum flows of the historical minimum. It turns out that the hydrological year 2014/2015 is being more critical than was 2013/2014. It is raining much less in October 2014 than it rained in October 2013. Then successively we are setting new records of low rainfall. ”
Governor announces works
During a visit to Suzano, Alckmin said the water supply to part of the Greater São Paulo was increased by 500 liters per second with the expansion of Guaratuba stream water transfer to the Alto Tietê system.
The Alto Tietê System is 10.4% by volume. It supplies 4.5 million people in parts of the east of São Paulo and Arujá, Ferraz de Vasconcelos, Itaquaquecetuba, Poa, Suzano, and part of Mauá, Mogi das Cruzes and Santo André.
The Alto Tietê should benefit, yet without undue delay the transfer of flow of the Billings Reservoir, as the governor said last week. This morning, he detailed the Alto Tietê has the capacity to treat and distribute the extra volume.
“Here (in the Alto Tietê) we have the capacity to treat five cubic meters per second and produce and distribute five cubic meters per second. It’s no use you put water in a location that does not have the capacity to treat more. Here you have both conditions. it is where you need, because that’s where less raining and it’s where you can help the Cantareira “he said.
The aid Cantareira System is indirect. Since the crisis began, the Alto Tietê began to serve one million more customers Sabesp, which were attended by the Cantareira. Because of migration and weak rainfall, the Alto Tietê showed acceleration in the decline of its reserves.