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Posts tagged Sobradinho Dam

Sediments Framing Northern Coast of Brazil

15.6S 47.8W

June 16th, 2012 Category: Clouds, Lakes

Brazil - May 8th, 2012

The northern coastline of Brazil is framed by bright green and blue sediments, probably accompanied by phytoplankton growth. Areas of “popcorn” clouds hang over the landscape near the coast – these clouds tend to form above photosynthesizing plants. Visible in the lower left corner is the bright green reservoir created by the Sobradinho Dam on the São Francisco River in the state of Bahia.

Sobradinho Lake and São Francisco River, Brazil

9.4S 40.8W

May 5th, 2010 Category: Lakes, Rivers

Brazil - April 29th, 2010

Brazil - April 29th, 2010

This image of Brazil includes parts of the states of Bahia (right), Tocantins (upper left) and Goiás (lower left).  Sobradinho Lake can be seen in the northern part of Bahia.  Its southern reaches appear tan from sediments, while the northern part is green in color.

It was created by the construction of the Sobradinho Dam on the São Francisco River. The reservoir itself is the largest in Brazil, covering a surface area of 4,225 km2. It has a mean depth of 8.6 m and a maximum depth of 30 m.

Sobradinho Reservoir in Northern Bahia State, Brazil

December 28th, 2009 Category: Lakes, Rivers

Brazil - November 15th, 2009

Brazil - November 15th, 2009

Sobradinho Lake is located in the northern part of the Brazilian state of Bahia. Created by the Sobradinho Dam, it is the largest reservoir in Brazil in terms of surface area.

The dam was built in the hydrologic basin of the São Francisco River at a distance of 748 km from its source and 1,912 km from its estuary on the Atlantic coast. The power generation was started on 31 November 1979.

The reservoir covers an area of 4,225 km2 with mean depth of 8.6 m and a maximum depth of 30 m. At the maximum elevation of 392.5 m above sea level, the reservoir accumulates 34.1×109 m3 of water with a regulated discharge rate of 1,060 m3 sec-1.

The geological formation of the region consists of very ancient rocks of the Brazilian shield, igneous or highly metamorphosed and dating back to the Precambrian era. The soils are predominantly latosol, quartz sand and lithosol.

The climate is semi-arid, characterized by very high evaporation rate. Mean annual rainfall ranges between 400 mm and 800 mm and mean annual temperature of 26-27deg C is affected by the water body of the reservoir.

The prevailing vegetation consists of caranauba (a type of palm tree), hypoxerophilous and hyperxerophilous shrubs of medium height, and low shrubs. When the water level becomes low, wet areas around the reservoir are cultivated.

São Francisco River Between Bahia and Pernambuco States, Brazil

8.7S 38.9W

December 21st, 2009 Category: Rivers

Brazil - November 28th, 2009

Brazil - November 28th, 2009

The São Francisco River runs along part of the border between the Brazilian states of Bahia (below) and Pernambuco (above). The 3,160 kilometre-long river is the longest river located entirely within Brazil.

The segment of the river on the right side of the image appears much wider than that on the left side due to water held behind several dams. Four hydroelectric plants and dams are located along the river’s course: the Paulo Afonso Dam, Três Marias, Sobradinho and Luiz Gonzaga (Itaparica)

In addition to being used for hydroelectric power, in 2005, the Brazilian government proposed a controversial irrigation project called the “Transposition of the São Francisco” that would bring water from the river to semiarid areas of four Brazilian states.

Environmentalists argue that the project will do more harm than good, benefitting only large landowners and a very small population, while bringing considerable ecological impact. The government, on the other hand, insists that the project will give the people in the four states a much-needed water supply.

Sediments from the São Francisco River Enter Sobradinho Lake

9.9S 42.1W

December 14th, 2009 Category: Lakes, Rivers

Brazil - November 28th, 2009

Brazil - November 28th, 2009

The São Francisco River empties tan sediments into Sobradinho Lake in the Brazilian state of Bahia. The sediments gradually diffuse into the lake, such that the waters near the inflow appear tan and those near the outflow appear dark green.

The lake itself is one of the largest artificial reservoirs in the world, with an area of 4,214 square kilometres (1,627 sq mi). The Sobradinho Dam, one of four hydroelectric plants built along the São Francisco River, has a storage capacity of 34.1 billion m3 of water.