Know It

It might be a blue-green algae bloom in surface water if you see:

• Strongly colored water (blue-green, green, yellow, white, brown, purple, or red).
• Paint-like appearance.
• Floating mats or scums.

• View More Images of Blooms

Avoid It

Always stay away from blooms in surface waters. View DEC's list of reported blooms:

• Don’t swim, fish, boat, or wade in areas with blooms.
• Don’t eat fish caught from areas with blooms.
• Rinse with clean water if you, your family or pets have contact with blooms.

If you are not on a public water supply and are using surface water:

• Bloom or no bloom, never drink, prepare food, or make ice with untreated surface water. You may also consider not using it for washing, especially if it looks cloudy.
• During a bloom, don’t drink, prepare food, or make ice with surface water, even if you treat the water yourself.
• Boiling water will not remove blue-green algae or their toxins. Learn more.

If you are on public water:

• Your water is treated, disinfected and monitored for drinking and household use. Learn more.

Report It

• Report blooms to: the DEC, your local health department, or harmfulalgae@health.ny.gov
• Report blue-green algae related symptoms to: your local health department or harmfulalgae@health.ny.gov
• Consider visiting a healthcare provider if you, your family, or your animals are experiencing symptoms related to blue-green algae blooms. Symptoms include diarrhea, nausea, or vomiting; skin, eye, or throat irritation; and allergic reactions or breathing difficulties.

Learn More

• More Details about Harmful Blue-green Algae Blooms
• Frequently Asked Questions
• New York State Department of Environmental Conservation (DEC)
• US Centers for Disease Control & Prevention
• US Environmental Protection Agency

HABs at Beaches

• Special Information for Public Beach Operators
• Harmful Blue-green Algae Bloom Sign Templates:
  • Warning Sign: Avoid Blooms While Swimming, Boating and Fishing
  • Beach Swim Area Closed Sign: No Swimming or Wading
  2015 Summary Report of Harmful Algal Blooms at Public Bathing Beaches (PDF, 354KB)

HABs at Water Supplies

• Special Information for Local Health Departments:
• Notification Templates for Harmful Blue-green Algae Blooms at Public Water Supplies
• Infographic: How Public Water Supplies Optimize Treatment During Harmful Blue-green Algae Blooms
• Infographic: How Drinking Water Health Advisory for Harmful Blue-green Algae Bloom Toxin Protects Public Health
• Harmful Blue-green Blooms: Understanding the Risks of Piping Surface Water into Your Home