Cantareira System water levels in São Paulo

The Cantareira System, the primary water reservoir for the São Paulo metropolitan area, has shown significant recovery following record rainfall in September. At the start of October, the system moved from the “alert” phase to the “attention” phase, with useful volume increasing from 32.99% in August to 41.1% in September.

Following this improvement, the National Water and Sanitation Agency (ANA) and SP Águas authorized Sabesp to increase water withdrawal to 31 cubic meters per second, up from the 27 cubic meters per second limit permitted during the alert phase.

By the end of October, the reservoir reached 51.2% of its useful volume, marking the first time in 16 months that capacity has surpassed the 50% threshold. Despite this progress, the system remains in the “attention” category, as the “normal” classification requires levels of 60% or higher.

Throughout November, the system will continue to operate in the attention phase. Under this classification, Sabesp is authorized to withdraw a maximum of 31 cubic meters per second, whereas normal operations (levels above 60%) would permit 33 cubic meters per second. Regulators continue to recommend water conservation and loss reduction measures for the approximately nine million people served by the system, including residents of São Paulo, Osasco, Guarulhos, and Santo André.