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What Will it Take to Rid the Region’s Ponds of Toxic Cyanobacteria Blooms?

Eve Zuckoff
Karen Malkus works at her lab bench in Barnstable Town offices.

Part Three of a three-part series

Biologist Karen Malkus’s laboratory in the Barnstable Town Officesfeatures a marble vanity with a mirror framed by light bulbs.

“It used to be …  the ladies’ room, which is now converted into the lab,” she said recently.  

Pipettes and amber bottles crowd Malkus’s lab bench. Mostly, she works with her microscope, and device called a “ZAPPR,” which isolates cyanobacteria in water samples.

“Anyway, let me show you. This is my favorite part,” she said, covering a glass slide with a drop of water. The slide, called a Sedgewich Rafter, has 1,000 tiny squares. 

“So you take the sample,” she explained. “This is from Long Pond, Centreville. … Can you see them? Can you see those little green flecks?”

Searching for ‘Bad Guys’

Under the microscope, she’s looking for a species of cyanobacteria that produces one of the most toxic natural poisons known, according to the Centers for Disease Control (CDC). When the level in the sample is too high, Malkus can order a pond closed to swimming.  

This summer, she had to issue pet advisories, warnings, and closures about 20 times, to keep people safe. In fact, Malkus maintains an email list to notify people directly.

“So that's why I focus on this,” she said. “It's to get a sense of the bad guys.”  

Right now, Karen Malkus is the only town employee on the Cape whose primary job is looking for these bad guys. That’s because Barnstable is the only Cape town with its own cyanobacteria monitoringprogram. 

Toxic cyanobacteria blooms are invading ponds all across the region as a result of excess nutrients from septic systems and warming global temperatures. They can be dangerous, but many people aren’t aware of the risks.

Map: Association to Preserve Cape Cod 

Experts say the Cape likely needs a tenfold increase in the number of ponds being monitored: from 50 to 500. That might seem like a big leap, until one considers how many ponds Barnstable County’s Department of Health and Environment is already testing for other hazards.

Improving Cyanobacteria Monitoring Through Region-Wide Efforts

“We have four beach samplers that go out to over 350 beaches every week,” said Bethany Traverse, who oversees Barnstable County’s Bathing Beach Monitoring Program. “So they're boots on the ground and they see with their own eyes what's going on in the ponds.”

For decades, the county has been testing 105 public and semi-public ponds on a regular basis, but only for fecal bacteria, like e. Coli. So why aren’t they monitoring cyanobacteria blooms? 

“Well, it's not monitored because the state does not have a requirement for cyanobacteria monitoring,” Traverse said. “They provide some support and funding for some of the testing that goes on. I would say it's probably not adequate.”

As the cyanobacteria problems grow, Traverse said she hopes the county can contribute to a region-wide monitoring program as soon as next spring. 

“The whole monitoring effort, I think, is kind of in its infancy right now,” she said. “And we're all sort of gearing up to find a path to improve that.”

For now,Traverse added, one of the best ways to monitor ponds is to teach the public what to look for and whom to call when they suspect a toxic bloom.

Confronting Toxic Blooms: Taking on the Source

But to some, better monitoring and more public education isn’t the answer.

“It is in no way a solution to say we're going to post warnings around these beloved waters and allow them to be degraded and that will keep the public safe,” declaredChristopher Kilian, a senior attorney with the Conservation Law Foundation (CLF). 

To Kilian, it’s better to solve the problem from the source. And the main source is septic systems that allow too much nitrogen to seep through the groundwater and end up in ponds, where it fuels cyanobacteria blooms. CLF is now asking a Barnstable County Superior Court judge to stop new septic system installations and inspections in two towns until the problem is under control.

“The first steps are first and foremost to stop approving systems that are going to make the problem worse based on the flimsy rationale that it's really hard and really expensive to do anything else,” he said. 

Kilian argued that a five-to-ten year plan, with the help of state and federal dollars, could solve the Cape’s cyanobacteria problem.

“Given the types of infrastructure investments that were made to the tunes of tens of billions of dollars to clean up Boston Harbor over many years and the great and dramatic positive outcomes in that example, alone, we view this as very solvable,” he said. 

More than 1,000 ponds are spread like jewels across the Cape and Islands. The fear for environmentalists, pond-goers and others is that without action, each pond becomes a potential danger to those who come to visit. And each one, they say, is a treasure worth preserving. 

This is the final installment of a three-part series on toxic cyanobacteria blooms. You can find them all here. 

Eve Zuckoff covers the environment and human impacts of climate change for CAI.