Cyanobacteria advisory issued for Shrewsbury’s Dean Park Pond 


A health advisory stood in front of Dean Park Pond as of July 13.
Dean Park Pond was previously put under a health advisory last summer due to elevated levels of E. coli. (Photo/Laura Hayes)

SHREWSBURY – Visitors to Dean Park in Shrewsbury and their pets should avoid contact with the pond until further notice due to high bacterial levels, according to town officials.

These high levels were reportedly caused by a bloom of cyanobacteria, which is also known as blue-green algae. 

The CDC reports that cyanobacteria are microscopic organisms that are naturally found in all types of water. Blooms form when cyanobacteria begin to quickly multiply. 

Harmful blooms could make toxins called cyanotoxins, which the CDC has identified as being “among the most powerful natural poisons known.” The cyanotoxins can make people and animals sick. There are no remedies to counteract these effects, according to the CDC. 

One cannot tell if a bloom has toxins by looking at it, the CDC said. 

Shrewsbury’s Board of Health and the Worcester Division of Public Health has issued an advisory for the pond. That advisory will remain in effect until tests indicate acceptable and safe water quality limits. 

In the meantime, the town is encouraging people and pets to avoid contact with the pond, including fishing, until further notice. 

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E. coli prompts health advisories in Shrewsbury