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A Boom Year For Blooms: Toxic Algae Closes Beaches, Raises Concern About Water Supplies

A beach on a cloudy day.
John Dillon
North Beach in Burlington was closed often this summer due to blooms of toxic cyanobacteria, also known as blue-green algae.

Call it the cyanobacteria summer for Lake Champlain and Burlington’s beaches.  The hot, dry weather came early and hung around for months. The heat made for perfect swimming days, but people seeking relief with a dip in Lake Champlain in Burlington were out of luck.

Officials were forced to close the city beaches a record number of times this year because of blooms of toxic cyanobacteria, a microorganism also known as blue-green algae. The blooms pose worrisome health threats, especially if they contaminate drinking water. Yet pollution and climate change means they’re likely to persist for years.

Guy with mask in front of sign
Credit John Dillon / VPR
Alec Kaeding is campground and beach manager for Burlington's Parks, Recreation and Waterfront department. He says the city closed beaches 44 times this summer.

Alec Kaeding was on the front lines of the cyanobacteria blooms this summer in Burlington. As the city’s campground and beach manager, he says one of the favorite parts of the job is walking around the campground early in the morning, listening to people waking up and smelling their campfires and outdoor grilling.

Kaeding is a big, easygoing guy who often punctuates his sentences with a hearty laugh. This year, he had to deliver bad news along with his warm welcome. Toxic blooms shut down the beaches 44 times this summer, compared to 11 times the year before.

“It’s frustrating for me, 'cause I want to see everybody have a lot of fun. It’s frustrating for my staff 'cause – same reason – they want to see everybody have a lot of fun,” he said. “And it’s very frustrating for the customer that packs up all the kids, comes down, wants to enjoy a nice day at the beach, and then the cyanobacteria hits. And it’s just a big letdown for everybody.”

On mobile? Click here to see infographic.

I catch Kaeding outside his North Beach office where his work  has shifted to the season of maintenance, repairs and writing budgets – all the jobs needed to get ready for another season on the shores of Lake Champlain. He said dealing with the blooms is now a summer routine for him and his crew.

“It’s a way of life, unfortunately, because I have to plan for it every year, drawing up plans for every beach in the city, how many signs we put out, and how are we going to close them, and daily checks and everything,” he said.

"It's a way of life, unfortunately, because I have to plan for it every year, drawing up plans for every beach in the city, how many signs we put out, and how are we going to close them." — Alec Kaeding, Burlington beach manager

Cyanobacteria are microscopic in size but devastating in their impacts. They produce toxins which have killed dogs and sickened humans. Exposure has even been linked by some researchers to the neurological disorder ALS, also known as Lou Gehrig’s disease. That’s why officials like Kaeding are quick to get people out of the water when they see a bloom.

Under the right conditions – like this summer’s hot and dry weather – the blooms spread extremely rapidly.

“I believe we had a two-day closure here at North Beach, where we found it at 11 [a.m.], and it was just one little spot, and within a half hour it had spread from Texaco all the way to Rock Point, and it was just pure pea soup,” Kaeding said.

Green soupy water
Credit Courtesy
Alec Kaeding took this photo of blue-green algae along Burlington's lakeshore over the summer.

For those unfamiliar with Burlington, that’s more than a mile of the city’s lakeshore coated quickly with an alien-like slime.

Cyanobacteria are always present in the lake. But warm, nutrient-rich water offer the prime conditions for the bacteria to explode.

More from VPR: Vermont's 'Jewels' Under Threat: Clearest, Cleanest Lakes Face Phosphorous Pollution

And these are the twin threats facing the lake. The lake stays warmer, longer due to climate change while phosphorus pollution from agriculture, stormwater and other sources continue to feed the blooms.

Kaeding sees the blooms and beach closings continuing until pollution control efforts pay off.

“It’s a long road, it’s not a quick fix, that’s for sure,” he said. “When we have blooms here and we educate the public, that’s the biggest thing, is educating everybody on what’s causing this, and what can we do as each person to help stop that.”

"I think it's fair to say that this is an area of concern in Vermont as well as nationally. You know, it's one of the contaminants of emerging concern that people are dealing with." — Bryan Redmond, Vermont Department of Environmental Conservation

Closed beaches are certainly an inconvenience. But 200,000 people also get their drinking water from Lake Champlain. While Vermont water systems have mostly not reported cyanobacteria contamination, that has happened just over the border in Quebec, with a public system that draws its water from Lake Champlain’s Missisquoi Bay.

A huge bloom on Lake Erie in 2014 also contaminated Toledo, Ohio’s water supply. More than 100 people got sick and the water couldn’t be used for drinking until the bloom cleared.

Bryan Redmond is director of the drinking water and groundwater protection division for Vermont's Department of Environmental Conservation. He’s part of a new work group between DEC and the Health Department that’s looking at cyanobacteria issues, including how to protect public water supplies.

“I think it’s fair to say that this is an area of concern in Vermont as well as nationally,” he said. “You know, it’s one of the contaminants of emerging concern that people are dealing with.”

More from VPR: 'It's The Dairy Sewer': Neighbors Say State Is Failing To Regulate Agricultural Pollution

The federal and state governments don’t set mandatory safety limits for cyanobacteria in drinking water, although they do have advisory standards. Redmond said the new work group may recommend additional state regulation.

“It’s seen a little bit of delay due to COVID, but it’s a strategic assessment that we’re engaged in to look at future regulation, our approach to managing cyanotoxins in Vermont, both in drinking water and recreational waters,” he said.

One public water system, in Grand Isle, did report cyanobacteria in the water in September at levels almost three times the state advisory limits. But Redmond said it was found in raw water – not the treated water sent to consumers – and that subsequent tests showed nothing.

Guy with flight jacket near river
Credit John Dillon / VPR
Clean water advocate James Ehlers says he's seen algae blooms below the falls on the Winooski River near his apartment in Winooski.

The Grand Isle test results were noticed by James Ehlers, a policy advisor to Lake Champlain International who routinely scours the state’s water quality databases.

He said the testing of water systems is spotty – usually only twice a week. He also questioned why the public was not told of the Grand Isle tests results.

“There was no public notification made at that point between the time that they resampled to get a safe sample,” he said. “So does that mean that for that period of days in between the unsafe sample and the safe sample, that the public was being exposed to cyanotoxins?”

Ehlers is running as an Independent for both the state Senate and the Vermont House. He’s active on social media and often blasts public officials for what he says is their failure to curb pollution. His blunt talk has made him a bit of a pariah among more mainstream environmentalists.

“In my world view, my ethical moral code says when I see a problem, I have an obligation to address it,” he said. “The protocols themselves are not protective of the public health. You pull a sample on a Monday, and you get a test result on a Wednesday, and then you resample to make sure it’s good, and then you don’t even notify the public?”

More from VPR: EPA Report Cites Progress On Lake Champlain Cleanup, But Activist Remains Skeptical

"The protocols themselves are not protective of the public health. You pull a sample on a Monday, and you get a test result on a Wednesday, and then you resample to make sure it's good, and then you don't even notify the public?" — James Ehlers, water quality advocate

The Grand Isle plant operator did not respond to a request for comment. But Julie Moore, the Secretary of Natural Resources, noted that since most water systems draw from deeper, cleaner parts of the lake, the supplies are generally safe.

“We continue to believe that the location of drinking water intakes in Lake Champlain do not appear to be particularly impacted by blue-green algae,” she said.

Phosphorus – the nutrient that flows off farm fields and developed lands – is the main fuel that feeds the blooms. Moore says this year’s drought meant less phosphorus pollution reached the lake. But the heat and warm water triggered the blooms still fed by phosphorus that built up over time in lake sediment.

More from VPR: State Sees Progress In Lake Carmi Phosphorus Cleanup

Moore said this “legacy” phosphorus shows that the lake’s environmental challenges were decades in the making and thus will take decades to resolve.

“There is a component of our water quality work that's an exercise in patience, but at the same time, underscores the importance of sticking with the impactful work we’re engaged in on the ground, from wetland restoration to stormwater management to agricultural stewardship projects,” she said.

The state has launched an ambitious, multi-million dollar program to reduce phosphorus from a variety of sources, including agriculture, eroding stream banks, and developed lands. The state’s Clean Water Board met last week to review some $30 million in spending proposals for water improvement projects statewide.

But until those efforts yield results, you can expect the blooms and beach closings to persist for years to come.

Have questions, comments or tips? Send us a message or get in touch with reporter John Dillon @VPRDillon

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John worked for VPR in 2001-2021 as reporter and News Director. Previously, John was a staff writer for the Sunday Times Argus and the Sunday Rutland Herald, responsible for breaking stories and in-depth features on local issues. He has also served as Communications Director for the Vermont Health Care Authority and Bureau Chief for UPI in Montpelier.
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