Blue-Green Algae Found in Sagaponack Pond

Cyanobacteria, also known as blue-green algae, was found in Sagg Pond in Sagaponack, Suffolk County health officials announced on Friday.  

Results from testing performed by researchers at Stony Brook University confirmed the presence of new cyanobacteria blooms. No one should swim or wade in the pond, and pets should be kept out of it, as well. 

Blue-green algae are naturally present in lakes and streams in low numbers, but in high numbers is forms blooms in shades of green, blue-green, yellow, brown or red. "They may produce floating scums on the surface of the water or may cause the water to take on paint-like appearance," the Health Department said.

If you come into contact with water that appears "scummy or discolored," according to health officials, rinse off with clean water immediately. Seek medical attention if you are experiencing nausea, vomiting, or diarrhea or have skin, eye, or throat irritations. Allergic reactions or difficulty breathing can occur. 

To report a suspected blue-green algae bloom at a body of water that contains a county-designated bathing beach, the Department of Health Services’ office of ecology can be contacted at 631-852-5760 between 8:30 a.m. and 4:30 p.m., or by email at

The Division of Water at the State Department of Environmental Conservation can be contacted to report a suspected blue-green algae bloom in a water body that is not a county sanctioned bathing beach at 518-402-8179 between 8 a.m. and 4 p.m., or via email at

The D.E.C.’s harmful algal bloom notification page features a comprehensive list of affected water bodies and can be visited for more information.