CHESAPEAKE BAY (WJZ) — A pollution forecast for the Chesapeake Bay predicts an increase in fish kills and dead zones.

For years, the Conowingo Dam at the mouth of the Susquehanna River has blocked sediment from flowing downstream into the Chesapeake Bay.

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“The dam is now full, so now, when you have large rain events, material is scored from behind the dam, so we’re getting more nutrients and sediment come into the bay,” said Beth McGee with the Chesapeake Bay Foundation.

That back up can’t stop the pollutants from farmlands up north and near-record rain from reaching the Chesapeake.

“That’s one of the challenges of saving the bay,” McGee said. “You look out on a day like today and you see a beautiful bay,”

Just because it’s beautiful, however, doesn’t mean the dead zones aren’t out there.

Environmentalists said these dead zones are in the main stem of the bay and parts of the Potomac River in deeper water.

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Chesapeake Bay Foundation officials said that could result in increases in fish kills.

They said they are hoping the EPA can convince legislators in Pennsylvania to act.

“They should be the enforcers, if states aren’t doing their share of pollution reduction, they should be holding them accountable,” McGee said.

Until then, officials call Conowingo Dam’s inability to stop the sediment a symptom of the problem- not the source.

“We’re always going to be at the whim of Mother Nature to some extent, in terms of wet years, but there are things we can do on the land to control the pollution,” McGee said.

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The report predicts this summer’s dead zones in the bay is expected to be about 2.1 cubic miles.

Paul Gessler