Which river carries the greatest average volume of water to the sea?

The Amazon River carries the greatest average volume of water to the sea of any river.

Its discharge at the Atlantic Ocean averages about 209,000 cubic metres per second, though the amount changes with seasonal rainfall. The river and its tributaries drain a huge basin covering parts of several South American countries, with most of the basin lying in Brazil.

The Amazon basin contains the world’s largest tropical rainforest and supports extraordinary biological diversity. Major tributaries include the Rio Negro, Madeira, Tapajós, and Xingu. The river’s enormous flow results from the basin’s size, heavy equatorial rainfall, and extensive network of tributaries.

The Nile is usually identified as the world’s longest river, but length and discharge are different measurements. River rankings can vary when sources use different definitions of a river’s source or mouth.