Physical dissymmetry of the continent notably affects the drainage of the continent. Owing to the position of the lofty Andes, major basins lie east of Andes, and the great rivers of South America drain into the Atlantic. The Pacific streams are short and swift. Along the coastlands of Peru, their waters are used for irrigation and, to some extent, for hydroelectric power.
Amazon is the longest river in South America (\(6,450km\)), stretching across equatorial South America. It is the largest river system in the world. This river has over a thousand tributaries.
Important tributaries of Amazon: Rio Negro, Madeira and Tapajos
At the point where it flows into the sea, the river is so wide and powerful that it flows even at a distance of 80 km into the high seas.
The Orinoco river originates in the Guiana Highlands and flows northwards into the Caribbean Sea. The Paraguay main tributaries are the Paraná and Uruguay rivers which form together and are known as the Platte River system. All the rivers are navigable for quite some distance in the interior.