Environment

Where are America's most toxic watersheds?

Despite the United States passing a Clean Water Act nearly 50 years ago to dramatically reduce pollution and restore America's waterways, toxic substances are still dumped into many water sources, threatening the health of people and ecosystems.

Here's a list of the 10 watersheds and locations in the U.S. that saw the greatest amount of toxic chemicals released into its waters in 2020, according to the Environmental America Research and Policy Center:

Lower Ohio-Little Pigeon - Toxics released:12,008,366 lbs. - States: Indiana, Kentucky

Upper New - Toxics released: 10,266,141 lbs. - States: North Carolina, Tennessee, Virginia

Brandywine-Christina - Toxics released: 6,191,362 lbs. - States: Delaware, Maryland, Pennsylvania

Lower Cape Fear - Toxics released: 5,017,810 lbs. - State: North Carolina

Muskingum - Toxics released: 4,640,523 lbs. - State: Ohio

Lower Big Sioux - Toxics released: 4,507,539 lbs. - States: Iowa, Minnesota, Nebraska, South Dakota

Lake Walcott - Toxics released: 3,866,978 lbs. - State: Idaho

Buffalo-San Jacinto - Toxics released: 3,784,822 lbs. - State: Texas

Middle Ohio-Laughery - Toxics released: 3,524,720 lbs. - States: Indiana, Kentucky, Ohio

Lower Rock - Toxics released: 3,069,016 lbs. - States: Illinois, Wisconsin

The companies listed in the report — APC Polytech LLC, Radford Army Ammunition Plant, Rio Tinto (owners of Kennecott Utah Copper Mine), The Chemours Company, Nucor Steel Marion Inc., Duke Energy, Lonza Companies (owners of Arch Wood Protection Inc.), CPS Energy — did not immediately respond to a request for comment.