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Conservation group warns of blue-green algae in Charles River

The Charles River Watershed Association issued a public health advisory after scientists found toxic blue-green algae by the Harvard Bridge and Museum of Science Thursday afternoon.Charles River Watershed Association

Thinking about bringing the dogs for a swim in the Charles? Think again.

The Charles River Watershed Association is warning that toxic blue-green algae has been found by the Harvard Bridge, which carries Massachusetts Avenue from Cambridge to Boston, and by the Museum of Science.

“Do not let your dogs swim in this area, cyanobacteria blooms are toxic to pets,” the group said in a tweet.

The advisory applies to boaters as well, who should avoid contact with the water.

Experts recommend that people and animals avoid areas of algae concentration. Those who come into contact with the water should rinse thoroughly afterwards.


The association, founded in 1965, was formed by “a group of concerned citizens” due to the declining condition of the water in Charles River, according to the group’s website. As one of the country’s oldest watershed organizations, the group has helped with cleanup and protection projects for decades.

The health advisory comes two days after members of the Charles River Conservancy launched an artificial island to study the effects that native plant species have on curbing the influx of algae blooms. If the island proves effective, new islands may be launched in the coming years.

Matt Berg can be reached at matthew.berg@globe.com. Follow him on Twitter @mattberg33.