As harmful algal blooms appear in more Adirondack locations, scientists and researchers work to figure out reasons why
By Mike De Socio
Harmful algal blooms (HABs) continued to appear across the Adirondacks this year and over a longer period of time, with multiple reports confirmed on Lake George and Lake Champlain throughout the summer and fall.
Two significant harmful algal blooms appeared in Lake George this season, one in July and the other in October, marking the third- and fourth-ever HABs in the lake’s history. Since the early October bloom, the state’s Department of Conservation has confirmed an additional “six small, localized shoreline HABs on Lake George.”
“It is worse,” said Lake George waterkeeper Chris Navitsky, who noted that the increase in HAB reports may also reflect an increased skill in spotting the nuisance algae.
On Lake Champlain, the DEC received 24 reports of potential HABs along the lake’s New York shoreline between July 6 and August 25 of this year. The blooms appeared as far south as Port Henry and as far north as Plattsburgh, according to the DEC.
Algal formations, many small in size, were also confirmed on at least six Adirondack lakes in September, October and November. Loon Lake in late October. Friends Lake in September (and also August). Paradox Lake on Sept. 13. Raquette Lake on Oct. 12. And Silver Lake on Oct. 5. Lake Clear and Otter Lake both had occurrences in August.
The number of water bodies statewide with harmful algal blooms has steadily increased since DEC started keeping track in 2012. The state logged 192 water bodies affected by HABs this year, up from 184 in 2020. A detailed archive of all HAB notices for 2021 can be found on the DEC website.
Too much of a good thing
So, what’s so “harmful” about algal blooms anyway? Well, it isn’t always a bad thing.
“Algae is natural, and you want some because it is the base of the aquatic ecosystem,” said Corrina Parnapy, author of the book “Algal Connections” and a biologist at the water quality consulting firm Avacal Biological.
Algae is the base of an important aquatic food chain, Parnapy said: Bugs eat algae, fish eat bugs, and on it goes from there.
“Without the algae, you’re going to have a messed up ecosystem, but when algae gets too much food, nutrients, they can bloom and cause nuisance conditions,” Parnapy said.
That’s what’s increasingly common in Adirondack lakes, due to a combination of factors. When excess fertilizer or unfiltered stormwater runoff ends up in lakes, it supplies algae with that extra boost of nutrients and leads to the harmful “blooms.” Those sludgy green blankets of algae not only make it unappealing for swimmers or boaters, but can also be toxic to humans.
“HABs can cause health effects in people and animals when water with blooms is touched, swallowed, or when airborne droplets are inhaled,” according to the DEC. (None of the blooms on Lake George have been determined to be toxic.)
Getting to the source of the problem
Fertilizer and stormwater runoff are not new issues in the Adirondacks, but they’ve been compounded by climate change. Warmer water temperatures lengthen the growing season for algae and allow it to float to the surface.
“Harmful algal blooms are very new in the Adirondacks,” Parnapy said. The first-ever recorded harmful bloom in Lake George appeared last year, and there have been more in the lake this year.
Navitsky, who has been working on Lake George for two decades, is using his research to figure out why there are an increasing number of HABs on the lake. Like Parnapy, he sees climate change as a factor. Shorter winters are giving algae more favorable conditions, for example, which may be why the lake is seeing HABs appear in the fall. Although the water is warmer in the summer, calmer water conditions (due to lower boat traffic) are also necessary for algae to rise up and congregate on the surface.
Navitsky also notes that the HABs in Lake George have been concentrated in the south basin, which is where the most development (and therefore the most fertilizer and stormwater runoff) is located.
While Navitsky and his team are out on Lake George nearly every day, the DEC has also empowered the public to help identify this issue, through its Citizen Statewide Lake Assessment Program. In 2019, DEC also released an online HABs map and reporting system for the public.
Preventing future blooms
Understanding and ultimately limiting the frequency of HABs in the Adirondacks is a team effort. And a lot of the prevention work actually has little to do with the lakes themselves.
One of Navitsky’s big priorities is the septic system infrastructure around Lake George. Aging septic systems can leach excess nutrients into the watershed and eventually the lake, and Navitsky hopes effective policies can help update the septic infrastructure.
“We want to limit nutrients going into the lake,” Navitsky said.
He also sees potential in working with planning boards to make sure new developments around the lake limit their environmental impacts and manage stormwater properly.
“How can we allow development to proceed but do it in a measure that we protect our important resources in our watershed?” Navitsky said.
Parnapy supports many of the same measures. “It’s a peak to shore approach. You want to start where the water is going to fall on the ground,” she said.
One piece of low-hanging fruit: Be smart about the use of fertilizers. If you’re fertilizing your lawn, don’t over-do it, and avoid areas that you know will runoff into nearby bodies of water, Parnapy said.
She also sees a need to upgrade wastewater treatment facilities around the Adirondacks to handle existing and future growth. “The more development we get, our wastewater treatment facilities are not going to be able to handle it,” she said.
New York state is also beginning to invest in HAB prevention. To date, New York has awarded $187 million in grants to projects designed to reduce the frequency of algal blooms statewide. It has also invested $11 million in research and development, pilot projects, and advanced monitoring of HABs. Much of that work is guided by the “Harmful Algal Bloom Action Plans” that New York has developed for 12 priority lakes across the state, including Lake George and Lake Champlain.
Parnapy summed it up best: “We all have a part to play in this, and we all impact the water quality.”
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