Brazil’s Drought Brings Water Supply to Near Zero Capacity at Hydroelectric Facilities

Gregory B. Poindexter

BRASILIA, Brazil Brazil is experiencing a debilitating drought as the nation endures the driest period since South America’s most populous country began keeping records in the 1930s. As a result of the arid conditions, reservoir levels and lake water flow to hydroelectric facilities that supply power to Brazil’s most densely populated city of Sao Paulo are nearing zero capacity.

According to the federal government, hydroelectric power facilities in the country’s southeastern region that supply power to close to 20 million people in the metropolitan region of Sao Paulo (MRSP) are being deactivated. A list of the deactivated facilities is not immediately available, but Brazil normally receives about 70% of its electricity from hydroelectric plants, according to energy officials.

The Billings Reservoir, in MRSP, supplies the 889-MW Henry Borden hydroelectric facility as part of the Cantareira water system. Local media outlets report Billings Reservoir is nearly dry.

Greater Sao Paulo, according to the World Bank, is the most important industrial producer of the country. Sao Paulo City, the world's ninth-largest city according to available 2012 census data, is located on the southeastern end of the Alto-Tiete River Basin. The city relies heavily on the Cantareia water system for hydroelectric energy to power industry, sanitation and drinking water.

Cantareia water system is formed by six reservoirs in five basins located in the Serra da Cantareira to the north of Greater Sao Pauloin the states of Sao Paulo and Minas Gerais. The system covers twelve municipalities, as well as the Guaru water treatment plant.

According to information from the state owned water utility, Companhia de Agua e Esgoto do estado de Sao Paulo (SABESP), the four-lake Cantareira water system is the largest of six reservoir systems that provide water to some 10 million of the 20 million people living in MRSP.

The six-reservoir system is linked by 48 km of tunnels and canals that provide flow for hydroelectric power and drinking water to MRSP and combined, the system is at or below 3% of its of its 264 billion gallon capacity.

SABESP is the largest water and sanitation company in South America. In the Alto-Tiete basin, the company provides urban water supply and sanitation services to São Paulo City and most municipalities of the basin, operating 195 water treatment plants and 350 wastewater treatment plants.

Because of the extreme water shortage brought on by the drought, SABESP has been forced to pump dead water -- water from reserves below the intake pipes of several reservoirs -- to use as drinking water.

For the Alto-Tiete system, water level stands at 10.5% against the 46.9% observed a year ago. Water reserves have plunged dramatically in the past 12 months, causing capacity in several reservoirs to reach all-time lows: Guarapiranga, from 77.3% to 46.9%; Alto Cotia saw the greatest decline, going from 86.3% to 32.8%; Rio Grande went from 93.7% to 74.3%; and Rio Claro diminished from 90.8% to 54.3%, according to the latest SABESP estimates.

On Jan. 19, Brazil’s national grid operator, Operador Nacional do Sistema Eletrico (ONS), cut power to several major Brazilian cities, including Sao Paulo and Rio de Janeiro.

The drought is also having an impact on energy supplies. Officials said with reduced generation from hydroelectric dams, demand for electricity generated from fossil fuel-fired plants will continue to peak as people turn up the air conditioning through the hot summer.