Seneca Lake: Algae may become toxic

SENECA LAKE—With the beginning of regular monitoring of Seneca Lake, researchers have been on the lookout for potentially toxic strains of blue-green algae. The New York State Department of Environmental Conservation (DEC) will be monitoring Seneca Lake to identify the strains of algae containing the bacteria that may be harmful to humans and warm-blooded mammals. While blue-green algae has been identified in Seneca Lake before, testing the lake will allow the townships to take the necessary precautions to eliminate the health hazard should a strain be located.
“I have identified strains of blue-green algae in the plankton,” Hobart and Willaim Smith Professor of Geolimnology and Hydrogeochemistry Dr. John Halfman said regarding his previous research in Seneca Lake. “I’ve been looking at it under a microscope, but microscopic identification will not completely identify if the species we find are toxic or not.”
While Halfman said he has identified blue-green algae in Seneca Lake in the past, he has not yet located it yet this summer. Despite this, he said there have been significant algae blooms already during the past few weeks.
“I’ve been out as late as [Thursday, July 10] and I haven’t seen blue-green algae species in the plankton yet, although there has been a significant bloom all this week and last week,” Halfman said. “The lake is really green.”
Halfman said there is a chance the algae could get to the point where it could cause a health hazard for those surrounding the lake. He said having such an intense bloom so early in the summer season is unusual.
“A lot of people would be mad,” Halfman said. “It would impact Waterloo and all the places that Waterloo gets water to which includes parts of Seneca Falls, parts of Romulus and Ovid, Geneva, including everything down to Watkins Glen and they feed water to other places south of Watkins Glen. All these places who provide water to the public would have to shut down or find ways to disinfect the water.”
Halfman said he routinely monitors the northern end of Seneca Lake along with a few other sites. He said warmer water temperatures are generally preferred by the algae, resulting in more blooms later on in the summer.
“They will proliferate in really intense blooms like we had this past week,” Halfman said. “They like slightly warmer water, the more turbid the water the better, where they do not compete with other algae under those conditions. Typically, that is why you will find them more in late August.”
According to the New York State Department of Health (DOH), the algae can cause health risks when consumed, inhaled through airborne water droplets or through contact with the skin. Consuming the water can have harmful effects on the liver and nervous system, while direct contact can cause irritation to the skin, eyes, nose, throat and respiratory system.
“If we do indeed have the toxic strains, then we wouldn’t be able to use the lake for drinking water,” Halfman said. “You wouldn’t be able to bathe in it, animals wouldn’t be able to swim in it, like dogs and other things, because the toxins are essentially toxic to all warm-blooded animals.”
Halfman said the algae tends to produce in lakes that have several different factors contributing a lot of nutrients into the system.
“Blue-green algae will proliferate in lakes that are very productive,” Halfman said. “The way you get a very productive lake is to have a lot of nutrients around, a lot of fertilizer. The way you get rid of it is to try to reduce the fertilizer input into the lake. You need to upgrade some wastewater treatment plants and put slightly stricter controls on septic systems people might have in their private homes, and also trying to reduce runoff from agricultural areas. It’s a big problem but we are slowly working on it.”
Halfman said they are in the midst of finishing up a Seneca Lake watershed plan, which includes ways to achieve reductions in nutrient input into the lake. He said some local communities surrounding the lake still need to sign a memorandum of understanding (MOU) to band together. Halfman said the plan would allow access to more state and federal grant money to perform necessary upgrades with a reduced cost.