World

Drought may force Brazil's biggest city to cut back water service to 2 days a week

  • A demonstrator hold signs that reads in Portuguese "The water is at its end, our patience too," as they protest against the rationing of water outside the official residence of Sao Paulo's Governor Geraldo Alckmin in Sao Paulo, Brazil, Monday, Jan. 26, 2015. The system of reservoirs and rivers that provide water to millions in this city have received less rainfall than hoped in the worst drought in more than 80 years, raising fears they won't be replenished as hoped. (AP Photo/Andre Penner)

    A demonstrator hold signs that reads in Portuguese "The water is at its end, our patience too," as they protest against the rationing of water outside the official residence of Sao Paulo's Governor Geraldo Alckmin in Sao Paulo, Brazil, Monday, Jan. 26, 2015. The system of reservoirs and rivers that provide water to millions in this city have received less rainfall than hoped in the worst drought in more than 80 years, raising fears they won't be replenished as hoped. (AP Photo/Andre Penner)  (The Associated Press)

  • A demonstrator wearing a mask depicting Sao Paulo's Governor Geraldo Alckmin protests against the rationing of water outside the official residence of the Governor in Sao Paulo, Brazil, Monday, Jan. 26, 2015. The system of reservoirs and rivers that provide water to millions in this city have received less rainfall than hoped in the worst drought in more than 80 years, raising fears they won't be replenished as hoped. (AP Photo/Andre Penner)

    A demonstrator wearing a mask depicting Sao Paulo's Governor Geraldo Alckmin protests against the rationing of water outside the official residence of the Governor in Sao Paulo, Brazil, Monday, Jan. 26, 2015. The system of reservoirs and rivers that provide water to millions in this city have received less rainfall than hoped in the worst drought in more than 80 years, raising fears they won't be replenished as hoped. (AP Photo/Andre Penner)  (The Associated Press)

  • Demonstrators hold signs that reads in Portuguese "The water is at its end, our patience too," as they protest against the rationing of water outside the official residence of Sao Paulo's Governor Geraldo Alckmin in Sao Paulo, Brazil, Monday, Jan. 26, 2015. The system of reservoirs and rivers that provide water to millions in this city have received less rainfall than hoped in the worst drought in more than 80 years, raising fears they won't be replenished as hoped. (AP Photo/Andre Penner)

    Demonstrators hold signs that reads in Portuguese "The water is at its end, our patience too," as they protest against the rationing of water outside the official residence of Sao Paulo's Governor Geraldo Alckmin in Sao Paulo, Brazil, Monday, Jan. 26, 2015. The system of reservoirs and rivers that provide water to millions in this city have received less rainfall than hoped in the worst drought in more than 80 years, raising fears they won't be replenished as hoped. (AP Photo/Andre Penner)  (The Associated Press)

The worst drought to hit Brazil's biggest city in decades may leave residents with water service only two days a week.

Sao Paulo water utility company Sabesp says a five days-off, two days-on system would be a last-ditch effort to prevent the collapse of the Cantareira water system.

The reservoir is the largest of six that provide water to some 6 million of the 20 million people living in the metropolitan area of Sao Paulo city. The utility says Cantareira is now down to 5.1 percent of its capacity of 264 billion gallons (1 trillion liters).

Sabesp official Paulo Massato Yoshimoto said Wednesday that "rationing could happen if rainfall does not increase in the reservoir area soon."