“Nutrient pollution” is caused by excess nitrogen and phosphorus entering our waterways. The excess nutrients can cause algae blooms, clouding the water, which decreases the sunlight in the water that plants need to grow and produce oxygen. As a result, oxygen in the water decreases, impacting the fish and other creatures that need the oxygen to survive. As the algae dies and sinks to the bottom it decays in a process that also consumes oxygen.

Over the last 50 years, the amount of nitrogen and phosphorus entering our waterways in the U.S. has increased dramatically. It has the potential to become one of America’s costliest and most challenging environmental problems. Nutrient pollution threatens our waters used for drinking, fishing, swimming, and other recreation. It can cause health issues for people and wildlife. Recreation, tourism, jobs, and our economy depend on clean water.