Georgica Pond Let Out, Water Quality Is Better

The East Hampton Town Trustees oversaw the traditional fall opening of Georgica Pond to the Atlantic Ocean on Monday. 

“It was very uneventful,” Jim Grimes, a trustee who was there, told his colleagues on Monday. The opening serves to flush the pond of toxins and restore salinity, and allows the migration of fish and crabs. 

Despite blooms of cyanobacteria (blue-green algae) in the pond this year, which prompted the trustees to close it to recreation and the harvesting of crabs and other marine life, “the water this year was fairly good,” said Sara Davison, executive director of the Friends of Georgica Pond Foundation, a group of property owners formed in response to the toxic blooms. Algae have affected the pond every summer since 2012.

“We have not had another disaster — devastating conditions — for three years now,” Ms. Davison said on Tuesday. “The pond never turned green” — water bodies with high levels of cyanobacteria can be green, blue-green, yellow, or red — “and they didn’t persist.” The algae can cause nausea, vomiting, diarrhea, skin, eye, or throat irritation; allergic reactions, or breathing difficulties if ingested. “In the disastrous years, the whole pond turned green, cyanobacteria counts were very high, and toxin levels were very high,” Ms. Davison said. 

This summer, dissolved oxygen remained at levels allowing marine life to thrive, she said, and anecdotal evidence — large numbers of crabs and baitfish — point to a healthy environment.

Christopher Gobler of Stony Brook University’s School of Marine and Atmospheric Sciences has overseen a water-quality monitoring program for the trustees and Friends of Georgica Pond for the last several years. In addition, Bradley Peterson, also of the School of Marine and Atmospheric Sciences, conducted a survey of the pond’s fish and crab populations this year. Those data have yet to be presented, Ms. Davison said, but “he said they caught a lot of species. Pond life seemed to be okay.”

Though naturally present in lakes and streams in low numbers, blue-green algae can become abundant, forming toxic blooms and causing hypoxia — low or depleted oxygen — and rendering a water body unable to sustain life. Excessive levels of nitrogen and phosphorus promote conditions in which harmful algal blooms can occur, and the Friends of Georgica Pond Foundation is encouraging the replacement of aging septic systems with state-of-the-art systems. 

For the third consecutive year, the foundation leased an aquatic weed harvester to remove macroalgae from the pond, a move driven by the belief that the release of nutrients it decomposes is nurturing and promoting cyanobacteria. This year, 93,140 pounds of aquatic macrophytes were harvested, representing a substantial increase over 2016 and 2017, in which 55,740 and 32,700 pounds were harvested, respectively.

While the trustees and the Friends of Georgica Pond Foundation point to a measure of success in their efforts to improve the health of Georgica Pond, cyanobacteria struck often in other South Fork ponds this year. Wainscott Pond, Sagg Pond and Poxabogue Pond in Sagaponack, Old Town Pond, Lake Agawam, Wickapogue Pond, Cooper’s Neck Pond, and Little Fresh Pond in Southampton, and Mill Pond in Water Mill all experienced cyanobacteria blooms. 

Cyanobacteria have also persisted at Fort Pond in Montauk, though the most recent water sample taken there, on Oct. 17, showed that levels at the northern and southern ends had fallen below the bloom threshold, said Laura Tooman, president of Concerned Citizens of Montauk. Sampling will resume next week.