São Paulo’s Cantareira water system enters alert level

The Cantareira system, which supplies water to about half of the Greater São Paulo population, fell to an alert status on 1 May as its usable volume dropped to 39.87 % of capacity, just below the 40.52 % recorded in April. The alert triggers a reduction in Sabesp’s allowed extraction from up to 31 m³/s to a maximum of 27 m³/s, though it does not immediately impose rationing.

To mitigate the shortfall, Sabesp can draw additional water from the Jaguari hydro‑electric reservoir, linked to Cantareira since 2018, and from sources in Minas Gerais that feed the system’s reservoirs. The agencies overseeing the system – the National Water Agency (ANA) and SP Águas – urge consumers to conserve water, noting that the dry season began in early June and the system will remain in alert until the volume stays in the 30‑40 % range for a week.

The alert affects more than 20 million residents and highlights the ongoing challenges of water management in Brazil’s most populous region.