What causes river water to turn brown?

Erosion from river banks brings soil into the river, changing its color. After heavy storms, many rivers run brown from all the runoff flowing into the river. Clay can cause rivers to be murky muddy brown, or yellow. Algal blooms are naturally occurring overgrowths of algae caused by sunlight, slow water, or nutrients.



People Also Ask

Sources of turbidity can include soil erosion, waste discharge, urban runoff, eroding stream banks, large numbers of bottom feeding fish, -- which can stir up sediment, excessive growth of algae, microorganisms and land development.

MORE DETAILS

Sediment — fine particles of sand, silt, clay and other soil materials suspended in the water — is the main cause of the river's brownish hue. Near Fort Snelling State Park in St. Paul, the murky Minnesota River flows into the relatively clear Mississippi. There's a distinct line in the water where the two rivers meet.

MORE DETAILS

The cleanest river in the United States is the Chattahoochee River. This river starts in the mountains of north Georgia and flows through the Atlanta metropolitan area. The Chattahoochee is one of the few rivers in the country that is still safe to swim in and fish in.

MORE DETAILS

Tara River, Europe Also known as the Jewel of Europe, Tara flows through the Balkan nations of Montenegro and Bosnia-Herzegovina. One of the cleanest rivers in the world, it is a UNESCO protected river under the World's Natural Heritage and the World's Biosphere Reserve.

MORE DETAILS