It is composed of five interconnected reservoirs that provide water to 9 million people in the São Paulo metropolitan area.

By 1960, the São Paulo state government, concerned about the high population growth of the city of São Paulo and neighboring towns, whose population has totaled 4.8 million inhabitants, decided to enhance the water supply of the Metropolitan Region of São Paulo, planning the construction of several reservoirs in the headwaters of Piracicaba River basin, thus beginning the Cantareira System.

In 1966, work began on the construction of reservoirs on the Juqueri River (today Paiva Castro), Cachoeira, and Atibainha.

In 1976, the Jacarei and Jaguari reservoirs were started by adding a capacity of 22,000 liters, second to the system.

[2] In 2014, low rainfall in the state of São Paulo led to a severe drought.