ARTICLES

Health officials urge people to avoid potentially toxic blue-green algae blooms
at Monterey's Lake Garfield

By Lauren Dorsey, The Berkshire Eagle
Jun 12, 2025 

MONTEREY — Officials are warning visitors to Lake Garfield to steer clear ofblue-green algae blooms, which can pose a health risk to people and animals.

Testing on June 3 revealed that the lake has elevated levels of cyanobacteria,also known as blue-green algae. The town put out an advisory about theblooms on June 5, and as of Wednesday, several blooms are still visible nearthe water’s surface.

“None of the blooms are near the public beach, and after reaching out to ourtown health agent Jim Wilusz, we decided an advisory was the right step,” saidTown Administrator Roger McDonald. 

Cyanobacteria is a naturally occurring organism that lives in water systemsacross the state. Usually, it's harmless, but when the right conditions comealong, including warm waters, sunlight, and high levels of phosphorus, thealgae can “bloom” or multiply rapidly — and potentially release a toxicchemical known as cyanotoxins.

In small amounts, contact with the bloom can cause stomach problems, skinirritation, or allergy-like symptoms but substantial quantities can result inliver or neurological damage.

“The blooms don’t stay in one place, which makes releasing an updatedadvisory difficult,” Wilusz said. “They can move around to other parts of thelake pretty quickly, so people need to be on the lookout for them.”

Should any of the blooms come near the swimming area, Wilusz said that thetown may consider closing the beach. In the meantime, he emphasized thatanyone around the water should use caution.

“We don’t want people swimming in it or dogs swimming near it, or anyoneusing the water for drinking or cooking,” he said.

While cyanobacteria blooms are relatively common in the Berkshires, Wiluszsaid in his time as a public health official, he’s rarely heard of one happeningthis early.

“Usually water temperature is a factor, but I don’t think the lake water is thatwarm yet,” he said .

According to Hillary Kenyon, a lake manager at Applied Watershed Sciences,several other lakes this year have also had early blooms.

“We’re going to see more of these as the summer goes on, and we’re thinkingabout offering just a blanket advisory this year, instead of chasing each ofthese down,” Wilusz said.

He said the Monterey Board of Health will be meeting on Monday andwill discuss setting a possible threshold for closing the swimming beach, anongoing strategy for releasing and updating advisories, and the results ofrecent testing.

Lauren Dorsey can be reached at ldorsey@berkshireeagle.com or 413-496-6190 

The state pulled back, the weeds pushed in. State push tolimit lake drawdowns sparks invasive plant surge, towns say

By Lauren Dorsey, The Berkshire Eagle
Jun 21, 2025 

MONTEREY — Wearing wetsuits and snorkels, divers have spent the last 10days scouring the bed of Lake Garfield, using suction hoses to removeEurasian milfoil, a perennial invasive.

The divers have been coming to Monterey since 2015 — shortly after theinvasive was first discovered — but this time, things were different.

“Usually there is almost no milfoil in this part of the lake,” said Dylan Alvarez, amember of New England Aquatic Services' Diver Assisted Suction Harvestingteam. “This year, it's everywhere.”

For the past decade, Monterey has typically supplemented the divers' workwith an annual 6-foot winter drawdown, or lowering of the water level, whichkills milfoil by exposing its roots to freezing temperatures.

This year, however, MassWildlife pushed back, discouraging the project. As aresult, the town cut its drawdown in half.

That change has had substantial consequences, locals say. The lake’s plant lifehas exploded and experts have said its continued growth could impact theswimming, boating and fishing that take place at the lake each summer.

The tensions unfolding at Lake Garfield over the town’s ability to usedrawdowns are part of a broader reevaluation happening at the state, which iscurrently revising its Massachusetts Guide to Lake Management.

The document, which is still being edited, encourages towns to move awayfrom annual drawdowns as a long-term solution for invasives and to largelyrefrain from lowering water levels by more than 3 feet. 

Beyond Garfield, several other lakes in the Berkshires — including Lake Onota,Lake Pontoosuc and Goose Pond — are already seeing the impacts of thisrefocus. Once published, the new guidelines will apply to lakes statewide.

'NOT BASED ON SOUND SCIENCE'

When Monterey submitted its notice of intent about last winter's drawdown,MassWildlife sent them a letter listing their concerns about the project.

“[MassWildlife] was very against the 6-foot drawdown,” said Hillary Kenyon, arepresentative of the town’s drawdown application and the owner andprincipal scientist at Water Resources Consulting.

In response to a request for comment, MassWildlife shared a copy of the letterthey sent to the town with The Eagle, but declined to comment further. 

The letter cited the drawdown’s potential harm to fish spawning, beaver damsand mussels, its relatively large size and the town’s historic failure to refill thelake by April 1.

In light of the state’s concerns, the town commissioned a professional study ofbeavers and a survey of mussels, both of which concluded that neither grouphad been harmed, according to Michael Germain, a member of the Friends ofLake Garfield nonprofit, and the town's Lake Garfield Working Group.

Kenyon said the town entered into negotiations with MassWildlife, but theclock was ticking. Eventually, they decided to submit a request that they feltwas likely to get approved — a 3-foot drawdown — rather than risk not havinga drawdown at all, according to Kenyon.

“The fact that [the state] opposes drawdowns, in my mind, is not based onsound science,” said Kenneth Wagner, the founder of Water Resource Servicesand a longtime consultant on Lake Garfield.

Wagner emphasized that he believes the research on drawdowns is insufficientand supports additional studies into their potential negative effects.

But in the meantime, Wagner believes the decision to halt drawdowns shouldnot be taken lightly.

“Come back to me when you have data,” said Wagner. “The data we have is forGarfield and it shows that the 6-foot drawdown works. It got disregarded.” 

“The people who will be blamed for this are the town. The state won’t take theblame for any of this,” said Wagner.

WHAT EXACTLY IS A DRAWDOWN?

A drawdown is an old and relatively inexpensive technique common across thestate, and it's a tool which Wagner estimates has been used at Lake Garfieldfor the better part of a century.

“Sometimes the mills would draw it down 20 feet or more,” said Wagner. “Inthe last decade, it's been a consistent 6 feet and it has done a very good job ofmanaging the milfoil.”

In a typical Massachusetts drawdown, lake managers will begin slowly lettingout water in October or November, at a rate of about 3 inches a day, until theyreach the desired level.

Drawdowns have become widespread in the Berkshires because they provideseveral benefits at a relatively low cost.

While the lake levels are low, perennial invasives like milfoil growing on thenow-exposed outskirts of the lake will dry out, freeze, and die. The lower lakelevel also prevents damage to private docks when the lake freezes, and hasbeen used by towns as a method of preventing flooding.

However, recent research, including a Ph.D. dissertation and several paperspublished by Jason Carmignani, who now works for MassWildlife, has indicatedthat drawdowns can also have some negative consequences.

Drawdowns expose more than just invasive plants to the air and cold, they canalso dry out and kill invertebrate animals, such as snails and mussels.

They may prevent fish spawning if the lake does not refill in time for spawningseason, and they could become less effective as climate change reduces thepredictability of lake refilling and freezing.

After decades of use, drawdowns also begin to change the composition of thelake floor that gets routinely exposed. It gradually transitions to a coarser,sandier texture, which also changes the composition of animals and plantsthat can thrive on top of it. 

CHANGING STATE GUIDANCE

Responding to some of these potential negative consequences, the state isconsidering updating its guidelines on drawdowns in its new MassachusettsGuide to Lake Management.

The guide is currently a draft. Right now, its authors are updating it inresponse to recent public comments.

Wagner helped write the current draft of the guide, although he emphasizedthat it was the product of a committee.

The guide, as it currently stands, discourages the use of drawdowns as a long-term strategy for managing invasives and requires towns who want adrawdown of more than 3 feet to “jump through a variety of hoops,” accordingto Wagner, which he believes is a largely positive change.

“Drawdown is really only useful at a very small percentage of lakes. Around 90percent of the lakes in the commonwealth really don’t need to be doing it.”

However, it may also make it more difficult for towns like Monterey tocontinue using drawdowns.

“Other lakes in the Berkshires are getting the same treatment as Garfield,” saidWagner. “I have no problem with responsible environmental management, butfor the ones that have had success and nothing seems to be seriously wrong, Idon’t see why you’d take the tool away.”

Once finalized and published, the guide will impact drawdown procedures andrequirements across the state.

'IN DANGER OF LOSING THE BATTLE'

But local experts argue that a smaller drawdown is already having substantialeffects on the lake — specifically the speed and extent of the milfoil’s advance. 

“For years we’ve been managing milfoil pretty well — it's nearly impossible toeliminate it completely,” said Germain. “Now, after just one winter, it feels likewe’re in danger of losing the battle. I don’t think anyone thought it would growback this fast.”

In a worst-case scenario, Germain says the lake is at risk of trending toward amonoculture.

“This is just the beginning of the season,” said Germain. “It’s hard to know justhow fast these plants will grow, and how much of the other life in the lakethey’ll outcompete.”

Native plants are also thriving — but together with the milfoil, the overgrowthis starting to choke the lake.

“Yes, we want to have native plants in the lake, but in some cases, I was seeingnative plant growth fill almost the entire water column to the point where itlooked like you could walk on certain areas, and this is still very early in theseason,” said Kenyon, who tested the lake several weeks ago. “If it continues, itcould impede recreation.”

Drawdowns are far from the only solution for invasive management. Othertechniques include hand harvesting, dredging and herbicides, which isperhaps the most viable substitute for Lake Garfield’s drawdown, according to Wagner.

Monterey has traditionally avoided herbicides, as many people in town remainskeptical of their impact and safety.

“Herbicides are said to be very safe, but I think the big question is what are theimpacts after decades of use?” said Justin Makuc, the chair of the MontereySelect Board. “The town has opted to avoid them.”

For Wagner, Germain, and Makuc, drawdowns seem to be the simplestsolution for managing the invasive.

“We’ve been doing drawdowns for so long that it remains my take thatwhatever damage might have been done, has been done,” said Makuc.

“It's a tradeoff, but in my opinion, at Garfield it's a good one,” Wagner said.

Lake Garfield isn’t the only town now wrestling with how to manage itsinvasives in light of the state’s potential preference against drawdowns.

“Many of the Berkshires most beautiful lakes also have some of the county’slargest drawdowns,” Wagner said.

And at many of them, including Goose Pond in Lee, which has a 6-foot annualdrawdown, state representatives have been attending recent meetingsencouraging the towns to move away from the traditional technique,according to Wagner.

“Everything has its costs and benefits, and the drawdown certainly has somecost,” said Germain. “This is a beautiful lake, and we want to do whatever theright thing is for it — but right now, the milfoil is getting out of control.”

Lauren Dorsey can be reached at ldorsey@berkshireeagle.com or 413-496-6190