Which river has the largest drainage basin in South America?. The river with the largest drainage basin in South America is Amazon–Ucayali–Tambo–Ene–Apurímac which receives inflows from a basin area of 7,050,000 square kilometers in Brazil, Peru, Bolivia, Colombia, Ecuador, Venezuela, Guyana and flows out primarily to the Atlantic Ocean. At second and third, are Río De La Plata–Paraná–Rio Grande with a drainage basin of 2,582,672 km2 and outflows to Río de la Plata, and Madeira–Mamoré–Grande–Caine–Rocha that receives inflows from a basin area of 1,485,200 km2.
( A drainage area is any area of land where precipitation collects and drains off into a common outlet, such as into a river, bay, or other body of water. )
Here are South America's largest rivers by drainage areas.
Amazon–Ucayali–Tambo–Ene–Apurímac is the largest river by drainage area in the world at 7,050,000 km2.
The river system, from Amazon River to Ucayali to Tambo to Ene and Apurímac river, is the longest river system in South America at 6,992km (4,344 miles), with its drainage area spreading across the width of the South American continent at an area of 7 million square kilometers (largest drainage basin in the world!). The Amazon river system is also the second longest in the world, with the Nile River system pipping slightly ahead at 7,088km.In terms of discharge volume, the Amazon river system is the largest in the world, discharging at 209,000 cubic meters per second onto the Atlantic Ocean.
Río De La Plata–Paraná–Rio Grande is the 2nd longest river in South America at 4,880 kilometers (3,032 miles).
The Paraná river system is the second longest river system in South America at 4,880 kilometers (3032 miles), after the mighty Amazon river. Draining from an area of 2,582,672 square kilometers, the Paraná river flows south-westerly through Brazil, Paraguay and Argentina at a rate of 22,000m3/s, before discharging onto Río de la Plata.
Orinoco is the 3rd largest river by average discharge rate in the world at 33,000 m3/s.
Orinoco is a 2,101-km long (1,306 miles) river that drains from a 1,380,000-km2 wide basin in Venezuela, Colombia and Guyana.
Orinoco discharges at 33,000 m3/3 and flows out into Atlantic Ocean.The Orinoco River is also known as Orinoquia.
Tocantins–Araguaia is the 3rd longest river in South America at 3,650 kilometers (2,268 miles).
The Tocantins–Araguaia river system stretches a combined 3,650 kilometers (2,268 miles); it is the third longest river system in South America and the longest river that is wholly located in Brazil. The river basin has a vibrant aqua-fauna ecosystem, including large mammals like the Amazonian manatee, Araguaian river dolphin and reptiles such as the black caiman, spectacled caiman and yellow-spotted river turtle.
Draining from a basin that is 950,000 square kilometers wide, the river discharges at a rate of 13,598 cubic meters per second.
Draining from an area as wide as 900,000 km2 in Brazil, Paraguay, Bolivia and Argentina, Paraguay (Rio Paraguay) has a length of 2,549 kilometers (1,584 miles).
The average volume of water flow is 4,300 m3/3 and the river flows out into Paraná River.
Negro is the 3rd largest river by average discharge rate in Brazil at 26,700 m3/s.
Negro is a river that is 2,250 kilometers (or 1,398 miles) long and drains from a 720,114 km2 drainage basin in Brazil, Venezuela and Colombia.
The average volume of water flow is 26,700 m3/3 and the river flows out into Amazon River.
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