The Amazon River Releases 20% of All Fresh Water That Flows Into Any Ocean

If you stood on the Atlantic coast of Brazil where the Amazon meets the sea, you would not just be looking at the mouth of a river — you would be looking at one fifth of the entire planet's freshwater discharge to the oceans, all flowing past in real time.

The Amazon's average flow rate is approximately 209,000 cubic meters per second — more than the discharge of the next 7 largest rivers combined. During the wet season, that figure can climb to over 300,000 m³/s.

Mind-Bending Stats

• Drainage area: 7 million km² — about 40% of South America
• Tributaries: over 1,100, of which 17 are over 1,500 km long
• Width: Up to 11 km in dry season, 50 km when flooded
• Bridge crossings: Zero, for almost the entire length
• Plume in the ocean: The freshwater plume reaches up to 400 km out into the Atlantic and is detectable from satellites

An Underground Twin

In 2011, researchers discovered that beneath the Amazon, at depths of 4 km, flows a second river — the Hamza — almost as long as the Amazon itself but flowing through porous rock. It moves only meters per year, but the volume is enormous.