The Boston Public Health Commission (BPHC) announced last month that Jamaica Pond was reopened less than a month after an algae bloom closed the popular recreational pond to swimming, fishing and boating.
“At the recommendation of the Massachusetts Department of Public Health (DPH), the public health advisory issued by the BPHC for Jamaica Pond on May 23, 2022, due to a suspected algal bloom has been lifted,” said the BPHC in a statement. “The pond is now reopened for recreational activities including fishing and boating. Swimming is generally not allowed on Jamaica Pond.”
The dangerous algea bloom that can make people and pets very sick was detected at Jamaica Pond at the end of May.
The BPHC issued the warning for the popular outdoor recreational space and temporarily closed the pond.
“The lifting of the advisory follows two weeks of consecutive tests of the pond water which demonstrated algal cell counts below the state’s safe limit,” the statement continued. “DPH generally recommends that recreational water advisories can be lifted when two consecutive weekly samples show algal cell counts below the safe limit of 70,000 cells/milliliter of water.”
The BPHC added analysis of testing of samples taken from the pond on June 7 and June 14 support the conclusion of DPH that Jamaica Pond is no longer experiencing a harmful algae bloom. On June 7, the level was 15,000 cells/milliliter and on June 14, the level had dropped to 9,200 cells/milliliter.
All signs that were posted were removed from the perimeter of the pond by June 16.
Blue-green algae can form harmful blooms in lakes, ponds, and rivers that make the water murky, and can sometimes make the water look like pea soup or paint. The bloom in Jamaica Pond appeared like a dull green discoloration that could be confused as otherwise safe pond water. The toxins in the algae may be present within the algae cells or in the water.
For humans, the primary concern is ingestion of water containing blue-green algae while swimming. Direct skin contact with the blue-green algae and inhalation of water droplets containing blue-green algae or toxins is a secondary concern. For dogs, the primary concern is the ingestion of water containing blue-green algae or scum that has washed ashore or gotten onto their skin or fur.