Main Brazilian Hydrographic Basins
 
 
  South Atlantic Basin 
east region
  South Atlantic Basin 
North & Northeast regions
  South Atlantic Basin 
Southeast region
  Platina Basin
  Amazon River Basin
  São Francisco River Basin
  Tocantins River Basin
 
 
Source: Statistical Annual of Brazil - 1992 - FIBGE
For a more detailed characterization, select the Basin of interest in the legend or in the map.
Brazil is endowed with a vast and dense hydrographic net, and many of its rivers are notable for their great width and depth. Due to the nature of the relief prevailing in the plateau, rivers that flow in its bed follow ruptures and deep valleys among other characteristics, that give them great potential for the generation of electric energy. With relation to navigability, those rivers, given their passage through irregular terrain, are not well suited for navigation. Among the great national rivers, just the Amazon and Paraguay are predominantly and broadly used for sailing. The rivers San Francisco and Paraná are the main plateau rivers.

In a general way, the rivers do not have their origins in areas of very high elevation, except the Amazon and some of its tributaries that originate in the Andean mountain range.

In general terms, as shown in the above map, we can divide the Brazilian hydrographic net into seven main basins: Amazon River Basin; Tocantins-Araguaia River Basin; South Atlantic Basin - region north and northeast; San Francisco River Basin; South Atlantic Basin - region east; Platina Basin, composed of the sub-basins of the rivers Paraná and Uruguay; and Atlantic South Basin - regions southeast and south.

Amazon River Basin
In 1541, the Spanish explorer Francisco de Orellana traveled from the nascent in the Peruvian Andeans, a distance of about 160 km from the Pacific Ocean, until he reached the Atlantic Ocean via the river that he baptized Amazon - due to fanciful visions, or imagination, of the existence of women warriors - the Amazons of Greek mythology.

This river, with a length of approximately 6,500 km or more (according to recent discoveries), disputes with the river Nile the title of the longest on the planet. There is no doubt that, in terms of water volume, the Amazon River is the largest in the world.

Its area of total drainage, in excess of 5.8 million km2, of which 3.9 million is in Brazil, represents the world largest hydrographic basin. The remaining area is divided among Peru, Bolivia, Colombia, Ecuador, Guyana and Venezuela. Such an area would embrace the European continent, with the exception of the old Soviet Union.

The volume of water of the river Amazonas is extremely high, discharging into the Atlantic Ocean approximately 20% of the total discharged on the whole planet. Its fluvial discharge is greater than the sum of the fluvial discharges of the next six larger rivers, being more than four times larger than the river Congo, the second largest in volume, and ten times larger than the river Mississipi. For example, in Óbidos, distant 960 km of the mouth of the river Amazonas, an annual medium fluvial discharge of the order of 180,000 m3/s is recorded. Such volume of water is the result of the characteristic humid tropical climate of the basin, that feeds the largest tropical forest of the world.

In Amazônia the largest and longest channels are used traditionally as navigation channels. Great oceanic ships can navigate to Manaus, capital of the state of Amazonas, while smaller branches, of at least 6 meters in depth, allow small ships to reach the city of Iquitos, in Peru - a distance of 3.700 km from its mouth.

The river Amazonas is a steady flowing river, possessing low declivity. Its medium width is of 4 to 5 km, but in some places it is more than 50 km in width. As it is intersected by the Equator, this river's tributaries are in the two hemispheres of the planet. Its main tributaries are the rivers it Iça, Japurá, Negro and Trombetas, in the left margin, and the rivers Juruá, Purus, Madeira, Tapajós and Xingu, in the right margin.

beginning of this page

Tocantins-Araguaia River Basin
The basin of the river Tocantins-Araguaia, with an area in excess of 800,000 km2, is in fact the largest hydrographic basin entirely within Brazilian territory. Its main river is Tocantins, whose source is located in the state of Goiás, to the north of the city of Brasília. Dentre the main tributaries of the basin Tocantins-Araguaia, stands out the rivers Sono, Palma and Melo Alves, all located in the right margin of the river Araguaia.

The river Tocantins ends in the Amazon delta and, although it possesses along its course several rapids and cascades, it also allows some fluvial sailing along its course from the city of Belém, capital of the state of Pará, to the locality of Peine, in Goiás, for about 1,900 km, in times of high water flow - although, due to dangerous obstacles originating from the rapids and sandbanks during the periods of drought, it can only be considered usable, for the whole year, from Miracema do Norte (Tocantins) onward.

The river Araguaia originates in the Serra das Araras, in the state of Mato Grosso. Its length is about 2,600 km, and it ends in the river Tocantins in the locality of São João do Araguaia, just before Marabá. In the extreme northeast of the state of Mato Grosso, the river is divided in two arms, river Araguaia, for the left margin, and river Javaés, for the right margin, for approximately 320 km, thus forming the Bananal island, the largest fluvial island of the world. The river Araguaia, is navigable about 1,160 km between São João do Araguaia and Beleza, even so it doesn't possess in this space any urban center of great prominence.

beginning of this page

South Atlantic Basin - North and Northeast regions
Several large rivers of regional importance can be mentioned as components of that basin: Acaraú, Jaguaribe, Piranhas, Potengi, Capibaribe, Una, Pajeú, Turiaçu, Pindaré, Grajaú, Itapecuru, Mearim and Parnaíba.

Especially, the river Parnaíba is formally the border of the states of Piauí and Maranhão, for all its length of 970 km, from its sources in the mountain of Tabatinga until the Atlantic ocean. It is also an important navigation channel for the transportion of agricultural products of the area.

beginning of this page

São Francisco River basin
The basin of the river San Francisco originates in Minas Gerais, in the Serra da Canastra, and it crosses the states of Bahia, Pernambuco, Alagoas and Sergipe. The river San Francisco possesses an area of drainage in excess of 630,000 km2 and a length of 3,160 km, possessing as main tributaries the rivers Paracatu, Carinhanha and Grande, for the left margin, and the rivers Salitre, Das Velhas and Verde Grande, for the right margin.

Of great political, economic and social importance, mainly for the northeast region of the country, it is navigable for about 1,800 km, from Pirapora, in Minas Gerais, until Paulo Afonso's waterfall, and this only due to the construction of electric generators moved by water, with their great lakes, as it is the case of Sobradinho and Itaparica.

beginning of this page

South Atlantic Basin - East region
In the same way that in its north and northeast region, the South Atlantic basin possesses several large courses of water of regional importance. Among others, the Pardo rivers, Jequitinhonha, Paraíba do Sul, Vaza-Barris, Itapicuru, Contas and Paraguaçu, are worthy of mention.

For example, the river Paraíba do Sul is located among the states of São Paulo, Rio de Janeiro and Minas Gerais, the states of larger economic meaning to the country. It possesses along its course several electric generators moved by water, and large riverine cities like Campos, Volta Redonda and São José dos Campos, as well as important industries as the National Metallurgical Company.

beginning of this page

Platina Basin, or Basin of the rivers Paraná and Uruguay.
The Platina basin, or basin of the rivers of the Prata, is constituted by the sub-basins of the rivers Paraná, Paraguay and Uruguay, draining areas of Brazil, Bolivia, Paraguay, Argentina and Uruguay.

The river Paraná is about 4,900 km in length, being the second longest in South America. It is formed by the junction of the rivers Grande and Paranaíba. Its main tributaries are the rivers Paraguay, Tietê, Paranapanema and Iguaçu. It represents part of the border between Brazil and Paraguay, where the bi-national electric generator moved by water of Itaipu was implanted, with 12,700 MW, the electric generator moved by water in operation of the world. Later on, it forms the border between Paraguay and Argentina. Due to its several falls, the river Paraná only possesses navigation capacities until the Argentinean city of Rosário.

The river Paraguay has a total length of 2,550 km, along the Brazilian and Paraguayan territories. It has as main tributaries the rivers Miranda, Taquari, Apa and São Lourenço. It originates close to the city of Diamantino, in the state of Mato Grosso, and drain areas of importance as the Pantanal Mato-Grossense. In its forward space it marginate the city of Assunción, capital of Paraguay, and it forms the border between this country and Argentina, until ending in the river Paraná, to the north of the city of Corrientes.

The river Uruguay, finally, has a total length of approx. 1,600 km, draining an area near of 307,000 km2. It possesses two main sources, the rivers Pelotas and Canoas, being born about 65 km to west of the coast of Atlantic. Do part of its basin the rivers Peixe, Chapecó, Peperiguaçu, Ibicuí, Turvo, Ijuí and Piratini.

The river Uruguay forms the border between Argentina and Brazil and, more to the south, the border between Argentina and Uruguay, being navigable from its mouth to the city of Salto, about 305 km to backward.

beginning of this page

South Atlantic Basin - Southeast Region
The South Atlantic basin, to the southeast and south, is fed by such locally important rivers as Jacuí, Itajaí and Ribeira do Iguape, among others. These rivers have regional importance, due to their role as navigation channels for transport of products and people, provisioning of water and generation of electric energy.

beginning of this page


 
The information given here was extracted of the site   Brazilian Environmental Mall
 
Page created and designed by Marlon Machado
Send comments to   marlon@brcactaceae.org 
Melocactus margaritaceus