March 21, 2014
Low Water Levels in Sao Paulo Reservoirs Worries City Officials
The lack of rainfall this growing season has not only impacted the crops grown in the state of Sao Paulo, there are growing concerns about water shortages all across the state of Sao Paulo and especially for the cities of Sao Paulo and Rio de Janeiro in southeastern Brazil. Record high temperatures and a lack of rainfall during December, January and early February lowered water levels in the region's reservoirs resulting in probably the worst water crisis in memory.
What worries people the most is the fact that the calendar has now turned to Fall which is generally considered the dry season in southern Brazil. Between April and October, this area of Brazil generally receives very little rainfall while temperatures remain warm. If those reservoirs are not refilled during the summer rainy season (November to March), there is very little chance they will be recharged during the dry season (April to October).
At one of the main reservoirs that supplies water for the city of Sao Paulo, the water level is at 15% of capacity which is the lowest ever recorded since the system was put in place 40 years ago. Last year at this time the level was at 60% of capacity.
The governor of the state of Sao Paulo has said repeatedly that there will not be a need for water rationing, but as the dry season approaches, many observers feel rationing is unavoidable. The governor indicated that they are putting in additional pumps at lower levels of the reservoir to pump out as much water as possible, but even by the state's optimistic estimates, there is only about four months' worth of water left in the reservoir regardless of how many pumps they install.
Rivers in eastern Sao Paulo, Minas Gerais, and Rio de Janeiro form the Paraiba do Sul drainage basin which provides the majority of the water for Rio de Janeiro and other cities in eastern Sao Paulo. Projects are being developed to capture and store more of the water in the basin, but those projects won't be completed for another 12-14 months, which does not help the immediate situation.
Four years ago a study conducted by the University of Sao Paulo indicated that the greater Sao Paulo area was at risk of serious water shortages and now those concerns have been born out.
Farmers in the state have already indicated lower crop yields for their corn, soybeans, sugarcane, coffee, and oranges as a result of the hot and dry conditions. There are additional concerns that the low water levels at the hydroelectric dams could also result in electrical shortages as well.