They went to try to get a read on how effective efforts to clean up last month’s mineral oil spill on the Muddy River had been, but Charles River Watershed Association (CRWA) staffers got more than they bargained for.
They encountered a potentially toxic blue-green algae bloom.
CRWA Water Resource Specialist David Kaplan told the Gazette it is unlikely that the oil spill and the phosphorus-fed bloom are related.
The bloom was in the Back Bay Fens area and was “at potentially harmful levels, based on guidelines established by the Massachusetts Department of Public Health (DPH),” according to a CRWA press release.
The CRWA “did not see any evidence of a bloom in the upstream areas near Jamaica Plain,” as of July 15, CRWA scientist, Julie Wood told the Gazette.
But “things can change fairly quickly,” she said.
She advised dog owners to bring their own water when they go on walks along the river; to think twice before letting their pets swim in the river; and to rinse them off if they do go swimming.
Certain species of blue-green algae—which is also known as cyanobacteria and is not actually an algae—can produce toxins that cause both acute and chronic liver and gastro-intestinal problems if ingested, and can cause a rash if it comes in contact with the skin, Kaplan said.
An overabundance of the bacteria also “prevents light from entering the water, alters water chemistry, and causes extreme changes in oxygen levels, harming fish and other aquatic organisms,” according to a CRWA press release.
He said the blooms are identifiable by their pea soup or neon green colors. The bacteria is fed by phosphorus, a common chemical in urban rainwater runoff, he said.
“We anticipate more blooms based on current weather patterns,” he said.
Low water levels in the river mean it is not flowing as quickly and the recent spate of “pulsing rainstorms” mean plenty of phosphorus-laden runoff is making it into the river, he said.
The CRWA does not have the funding available to conduct systematic testing of the river, Kaplan said.
Researchers at Northeastern University have been planning to conduct a blue-green algae study this summer that includes the Muddy River, Kaplan said. But, especially given how ripe conditions seem to be for the cultivation of the toxic algae, “Money should be set aside by the state,” for a comprehensive monitoring plan, he said.
Anne Monnely, acting director of the state Department of Conservation and Recreation’s Office of Water Resources said testing for toxicity in the Charles is a largely volunteer-based effort. That waterway has been a priority for monitoring because swim races are planned there for this summer, she said.
She is unaware of any plans to up the level of monitoring in the Muddy River, she said.
Wood told the Gazette that the CRWA’s attempts to visually observe the effects of the oil spill cleanup were inconclusive.
“With so much runoff from the roadways and parking lots, it is hard to say conclusively when you see an oil sheen if it is an effect of the spill,” she said.