Biggest reservoir for Brazil’s largest city is running dry

Halfway through the rainy season, the key reservoir for the hemisphere’s largest city holds just six percent of its capacity, and experts warned Friday that Sao Paulo authorities must take urgent steps to prevent the worst drought in more than 80 years from drying it out. The system of reservoirs and rivers that provide water to millions in this city have received less rainfall than hoped during the first weeks of the wet season, raising fears they won’t be replenished as hoped. Rainfall during the first two weeks of January totaled less than 3 inches, well below the historic average for the month of 10.7 inches.

The water supply situation is critical and could become even more critical if the lack of rain and hot weather continue and effective demand management techniques are not created.

Mario Thadeu Leme de Barros, head of the University of Sao Paulo’s hydraulic engineering and environmental department

The biggest problem is in the Cantareira water system, which is the largest of six reservoirs that provide water to some 6 million of the 20 million people living in the metropolitan area of Sao Paulo city. Cantareira is now down to 6 percent of its capacity, the water utility Sabesp said on its website. Although declining water supplies have been a concern since last year, authorities have resisted rationing water. But Leme de Barros said officials need to consider a range of steps, among them implementing water rationing but also encouraging the use of more efficient appliances, lowering water pressure in the system and doing better at repairing leaks.

World Brazil drought