Data from the National Water Agency (ANA) and Sabesp show that the reservoir system that supplies the metropolitan region of São Paulo has water volume below half, one of the lowest levels for the month of September since the beginning of the historical series. The system is operating at 49.7% of capacity, which puts it in a state of alert. On August 31, it was 55.6%. The alert state is triggered when the useful volume reaches 40% of the reservoir.
According to the institutions, in 2024, there was not a single month in which water entered the Cantareira system above the historical average. In previous droughts considered historic, such as those of 1953-54 and 2014-15, the month of September had the highest water entry (inflow) into the Cantareira.
The drought in the region has led to the maintenance of an average pumping rate in the Paraíba do Sul River Basin above 7 cubic meters per second since June.
The average rainfall in September in the springs that supply São Paulo was below the historical average. The expected sum of rainfall was 637.2 mm in the seven reservoirs, but it was 114 mm this year, just 17.9% of what was expected.
In 2014, when the system had six reservoirsthe average was 547.4 mm and precipitation was 569.1 mm. In 2022, when the operational volume available in springs was 42.7% at the end of September, 500.4 mm of rain fell.
According to ANA, the region has already gone through 66% of the dry period this year.
