Traditional swimming season may be over, but harmful algal bloom season is not.
Moreau Lake had another suspicious bloom earlier this month, marking its potential third this summer. In Washington County, Cossayuna Lake and Summit Lake both have confirmed blooms, and Dead Lake has had a suspicious bloom.
The reported harmful algal blooms are listed on the state Department of Environmental Conservation’s notifications page, which is updated every Friday during the summer and early autumn months.
Harmful algal blooms are actually called cyanobacteria. They occur naturally in bodies of water, but sometimes can be toxic. The toxin most commonly found in New York’s waters is called microcystin, a kind of liver toxin. Swimming in a toxic bloom can cause health problems including skin rash, respiratory problems, diarrhea, nausea and headaches. Pets and livestock are also at risk if they swim in a bloom, because they could lick their fur or hair and get a high concentration of the toxin, which has been known to kill them.
None of the lakes reported to have harmful algal blooms this month have had confirmed high levels of toxins, but the DEC has confirmed that Cossayuna Lake and Summit Lake have the cyanobacteria species that can produce toxins. Scientists are still trying to uncover why some blooms become toxic and others do not.
State agencies recommend avoiding all blooms, whether they’re tested specifically for toxins or not.
New York State Parks Recreation & Historic Preservation said Moreau Lake’s beach had officially closed after Labor Day, but harmful algal bloom signs were posted and park staff notified campers of the latest suspicious bloom. This is the first reported year since at least 2013 that the lake has had harmful algal blooms.
The blooms are no stranger to Cossayuna Lake, however, which according to the DEC had one with high toxins in 2013, followed by confirmed blooms in 2014 and 2015 and a suspicious one last year.
Sheila Rappazzo, board member of the Cossayuna Lake Improvement Association, said this year has been bad for blooms because of the hot temperatures and heavy rainstorms. While the lake does not have any public beaches, the association has sent out emails, warning residents of a bloom at the end of August and the most recent one reported around Sept. 15.
Volunteers with the Summit Lake Association discovered a small bloom about two weeks ago, in between two boats along the shoreline, said J. Michael Lockhart, president of the association. Members who have provided the association their email addresses were notified, Lockhart added.
According to the DEC’s archives, Summit Lake has had suspicious blooms reported in 2013 and 2016 and a confirmed bloom in 2017.
Dead Lake, a popular fishing spot in the town of Jackson, has not had any blooms reported to DEC since at least 2013. The suspicious bloom was reported on Sept. 12. Studies are still being conducted on toxins accumulating in fish, the DEC said on its website. It adds that some states recommend cleaning fish fillets before cooking or freezing, and points to the New York Freshwater Fishing Guide, which advises anglers against eating fish “caught from areas that have the thick paint-like or pea soup-like coloration characteristic of cyanobacteria blooms.”
To learn more about harmful algal blooms, how to report one and to see the DEC’s weekly update of affected water bodies, visit dec.ny.gov/chemical/77118.html.