Deadly blooms of algae kill fish and sicken people along the Eastern seaboard, from North Carolina to Maryland. Mercury-contaminated rain falls from the sky into the Great Lakes and Lake Champlain, making fish unsafe to eat.
Sediments choke rivers in the Pacific Northwest, endangering once-plentiful wild salmon.
Polluted runoff includes nutrients from agribusiness, sediments from logging, and metals from city streets. Rain contaminated with pollutants like mercury comes from many sources, ranging from coal-fired power plants to medical waste incinerators. Click on map to learn how your state compares. TMDLs are pollution caps that states must impose to clean up polluted waterways. States must determine how much pollution a waterway can handle and divvy up the allowable loads among the sources of that pollution.