Lake stewards and others learned more about what's behind growing troubles with harmful blue-green algae

Harmful blue-green algae once again this year plagued an alarming number of lakes statewide, including water bodies throughout the Finger Lakes region.

Scientists and other experts are wrestling with the problem, which prompted a presentation last week hosted by the Canandaigua Lake Watershed Association. Tony Prestigiacomo, research scientist with the state Department of Environmental Conservation’s Finger Lakes Watershed Hub, presented a crowd last Wednesday with more food for thought as everyone — from lake homeowners to boaters, swimmers and those concerned with their drinking water — sought to learn more.

In September, lab samples confirmed high toxins from blue-green algae in Canandaigua and Keuka lakes. This was the second season in recorded history that Canandaigua Lake suffered a toxic algae bloom, the first time being in 2015. Seneca Lake also had its first bloom two years ago, then again last year. While Honeoye Lake typically has blooms due to its small size and warm waters, others of the Finger Lakes are now at risk due to the effects of climate change and other contributing factors.

“A smaller farm pond will never be like Canandaigua or Skaneateles lakes,” said Prestigiacomo. He said that small, shallow water bodies with warmer water provide a hospitable breeding ground for algae. What is concerning now is what’s happening in the larger lakes — ones historically considered pristine, like Canandaigua and Skaneateles, which are becoming ripe for harmful algae.

In September, Skaneateles Lake had its first blue-green algae bloom on record with certain areas of the lake showing high levels of toxins. Some algae had made it into the city of Syracuse's intake pipes dozens of feet below the lake surface. The city began adding extra chlorine to the drinking water after a sample tested positive for the toxins.

Health officials said that none of the toxins, called microcystins, reached anyone's tap water in the Syracuse drinking water system since the bloom began in September, according to a Nov. 13 report. But Dr. Indu Gupta, Onondaga County health commissioner, warned it was not possible to say the same for private systems.

Prestigiacomo focused on phosphorus, an essential element for plant life and not a problem when in balance for a healthy lake. But when too much phosphorus is in water, it can suffocate healthy plant life in rivers and lakes — making it the perfect storm for blue-green algae and other troubles. For people in the business of managing watersheds — and many of them attended last week’s talk — Prestigiacomo revealed how phosphorus exists in multiple forms, not all of which encourage algae. It was information watershed managers could use in always trying to do better.

The Finger Lakes Watershed Hub, established late last year, is part of an effort to increase research and find ways to mitigate the algae problem plaguing the lakes. Prestigiacomo’s specific interests are in water quality monitoring and interactions between lakes and streams, among other factors.

Among those attending the talk were Kevin Olvany, Canandiagua Lake watershed program manager, and Terry and Dorothy Gronwall from the Honeoye Lake Task Force. The Gronwalls live on Honeoye Lake and have been conducting monitoring on the lake for more than a decade.

What is the take-away for the average person? The Gronwalls said that as scientists learn more, the old rules still apply. Those include picking up after your dog, being mindful to keep brush and pollutants out of waterways, making sure your septic system works properly and is up to date, and supporting programs and projects kind to the watershed.