Algal blooms, which can occur in nutrient-enriched waters, cause thick, green muck that pollutes the water and can be harmful to aquatic life, the environment, and to the economy. Some algal blooms produce toxins that are dangerous to people. People should avoid contact with waters that have harmful algal bloom advisories posted or anywhere the water is pea green, discolored, or has floating mats.

For more information, visit www2.epa.gov/nutrientpollution/harmful-algal-blooms