By Alex DeMetrick

CONOWINGO, Md. (WJZ) — The amount of rain Maryland has seen this week means a lot of swollen rivers due to runoff.

Among them is the Susquehanna River.

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Even if all our recent rain lets up, the effects from all that water are far from over.

To ease pressure on Conowingo Dam, 15 spill gates were opened and it is anticipated 18 will be opened by 12 p.m. Thursday. With all that unleashed power comes genuine worry.

According to Rob Newberry, the chairman of the Delmarva Fisheries Association, it’s about the “catastrophic impact this is going to have downstream for the commercial fisheries and the environment here in the Chesapeake Bay.”

The worry centers on what’s behind the dam.

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According to Charles Macleod with the Clean Chesapeake Coalition “above Conowingo Dam is a 14-mile reservoir that for the last 90 years has been filling with sediment that’s contaminated with other pollutants.”

In 2011, Tropical Storm Lee sent a sediment plume down the Bay to the Potomac River, devastating the upper part of the bay. Conditions could be shaping up to do it again, as trapped sediment gets scoured out of the reservoir.

“This volume of water and the turbulence grabs what’s up there and hurls it into the Bay,” says Macleod.

“There’s going to be millions of tons of sediment coming down the bay, covering oysters, what crabs can’t get out of the way,” a very concerned Newberry added, “It’s going to drive the fish, it’s going to destroy the grasses and it’s going to be an epic problem.”

And there is a very real possibility more spill gates will be opened in the days ahead.

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