Mystic River fish kill not caused by recent oil spill, MassDEP says

SOMERVILLE, Mass. — The state is investigating a fish kill along the banks of the Mystic River near Assembly Row in Somerville.

The fish are all along the banks floating or washed up on the shore at Draw Seven State Park. It's not a pretty sight. The state is trying to pinpoint what caused this and right now believe the warmer water temps may be a factor.

The Mystic River in Somerville is a popular place for people to enjoy the atmosphere near the water, just killing time.

But the regulars were shocked this week to find dead fish littering the banks.

“This is unusual, I’ve never seen this before,” David Mussina told Boston 25 News.

Dead menhaden have been washing ashore on the banks of the Mystic behind Assembly Row just across the river from the soon-to-be Encore Boston harbor Casino.

“All of a sudden, to see thousands of dead fish was really surprising and concerning,” Jon Brickman said. “I thought this is kind of bad for the casino with the dead fish along the river.”

There are containment booms in the water because there was a recent oil spill. The state says they did come down and test the water near the dead fish, but did not find any hazardous material.

MORE: Experts worry as herring get stuck on Upper Mystic Lake Dam spillway

Massachusetts Department of Environmental Protection officials were on scene looking into whether warmer water temperatures were a factor.

The Mystic River watershed association has also visited the site and is monitoring the fish kill. It says warmer water has lower levels of oxygen; so, if the menhaden were driven into the warmer water, the lower oxygen levels could have killed the fish. But the state says it is still trying to determine that.

The locals say while it's not pretty -- they're not too concerned right now.

“If I saw it happen over a few days, week after week then I would be concerned about it,” George Connolly said.

State DEP officials say this is the second call for dead fish at this part of the river in the past two weeks.

MORE: Concerns growing over "significant" oil spill in Mystic River

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